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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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 Posted: Sun Feb 10, 2019 5:49 pm Post subject: Electrical nightmare |
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So on day 8 of this and I now have no hair left to pull out. If any good souls out there can help I would be forever grateful and happy to send a case of beer if you are close!
So the basics of the car. 1974 beetle sedan engine and suspension. 1972 pan to match. New wiring harness placed in 2 years ago. Car was running for the past 2 years and then this wonderfully horrible puzzle has reared its head.
Delightfully bobbing down the road 1.5 miles from the home when the entire thing went dead. Coasted into a church parking lot and found some smoke and fried wire insulation at the coil. More about this later.
A quick AAA tow back to the house and went to work for the past 8 days. About 45 hours later and this is what I went through. Highs and lows.
INITIAL THOUGHTS:
Figured the stainless steel spark plug wires did not have a big enough gauge wire and it jumped to the coil. Dont hold me to this but that was my suspicion.
RAN NEW WIRES:
Ran new wire from choke/carb (stock single carb) to igition coil. Found this was possible pinched and maybe grounded as insulation was burnt off. Pulled the condenser from the svda distributor and put on a new one as the wire was fried. Under the distributor dust cover I replaced the internal black insulated wire as it was fried. Removed and got rid of the stainless steel spark plugs and replaced with the stock version from Jbugs.
Tach wire, reverse wire, and igition wire from igition switch seemed fine so left them all.
TURN OVER RESULTS #1
Tried to turn over and as it did rotated I didnt get a spark. Checked the fuel line, fuel filter, carb reservoir and all good. Removed the filter and direct connected to be sure I wasn't pulling air from a crack. Still no igition.
NEXT ATTEMPT
Ran a test wire from the igition switch to the coil just in case the wire was fried somewhere. No turn over. Direct wired it to a got lead in case it was the igition switch and no joy. Figured I would replace the coil just in case as I had one here new. Put the new coil in.
DISTRIBUTOR ATTEMPT
Pulled the distributor and put in the 009 I had from the original 74 engine. Checked and tried with the igition coil direct to a hot lead. BACKFIRE! I was hopeful. Oh silly me.
Checked TDC and the 009 was 90 degrees off. Checked twice and got it timed up.
Cranked and it ran. It didnt have the SDVA so it had to be feathered but it ran. Was hopeful! Stopped the engine with the inline battery disconnect switch since the coil was direct wired to a hot lead and would not cut off with the igition switch.
Ran the original wire for the coil and tried again. No luck. Figured the wire was fried somewhere. Ran a new 16 gauge from coil, through body, and to the igition switch. Figured all was good.
CRANK ATTEMPT PARK 2
So with the new wire I tried to crank and nothing. No spark again. I was at a loss.
MULTIMETER TRIES
So pull out the multimeter and got to work again.
Tried to narrow it down and i will spare you the details of every wire i checked for 3 hours.
Before i start let me say it does have a new negative battery terminal braid to the chassis that was replaced 3 years ago and it is in good condition still. I seem to be getting sporadic voltage to the coil. I ended up moving the coil wire back to a direct hot just to try to help in diagnosis. No joy still on getting it to run.
Voltage on the battery was sitting at 12.2-12.5 and the starter runs fine. Figured that would eliminate the battery and the positive to the starter. Tested some of leads at the fuses. Headlights and ACC seem to have a good voltage around 11.6 from wire to the ground screw they are attached to. Checked ignition coil/ignition hot in from terminal to battery negative and it was good but in ny head wondering if this is constant.
Checked igition coil in on multimeter. Now it could be my meter or me finding a good ground but sometimes it would be 0 and some a good volt. New wire and all. Left battery on and igition in run and took a break to see if the coil would heat up. After 15 minutes it was hot. Turned off and then a few minutes turn all back on and tried to start. Still no joy.
CURRENTLY
Currently I am done for the week with this. About a day from trying to find a shop in Charleston SC to help with the issue. I like to do things myself but might be at the end of my rope for this one!
Anyone have any thoughts? Miracles? Small VW gnomes that work at night mysteriously with their magic?
Thanks for the read and hoping for some luck from the Samba world out there!
_________________
'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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viiking
Samba Member
Joined: May 10, 2013
Posts: 2667
Location: Sydney Australia
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| Posted: Sun Feb 10, 2019 6:19 pm Post subject: Re: Electrical nightmare |
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I'd change the coil a second time. I would also check the grounds and resistance of the wires using a multimeter. I think you might have done this.
This is the reason I say to NOT discount a second bad coil and is something I posted on another post. Given you say you have intermittent voltage, look at the bleeding obvious and work your way back to the more unlikely.
Rule No 1.
Always check the bleeding obvious!
I once had a problem with my VW, it ran like a dog. I checked the spark plugs and one was not firing. Changed the plugs to new ones. No change. Changed the points. No change. Replaced the condenser. No change. Changed the leads. No change. Changed the coil. No change.
Did I ever think that the new spark plugs had one faulty one. DOH!
But then. I had a really nicely refurbished electrical system, even though it was costly! |
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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Sun Feb 10, 2019 6:30 pm Post subject: Re: Electrical nightmare |
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Definately a possibility. The irregular voltage is from the feed side as well at the coil out so that threw me for a loop
_________________
'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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sb001
Samba Member
Joined: May 19, 2011
Posts: 10406
Location: NW Arkansas
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| Posted: Sun Feb 10, 2019 6:58 pm Post subject: Re: Electrical nightmare |
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Some questions:
#1. When you moved the coil wire to a hot lead, where EXACTLY did you move it to? Another fuse on the fuse block? If so which one? The coil gets its power from the ignition switch yes, but it comes off the fuse box. There is another black wire from the ignition switch to your #11 fuse on the fuse box, which then bridges over to #12 fuse (on the unfused side of the box) and your black coil wire comes off that unfused side of #12. I would stat by using my multimeter to check for 12 volts on that black wire from the ignition switch to the fuse box and make sure that's good first (key on in RUN position). If you have 12 volts there, then make sure the coil wire connection at #12 fuse is good, and the metal bridge on the box from #11 to #12 is good. If all that is good, with key still in RUN position, take your multimeter and check for 12 volts on the other end of that wire at the coil. If you have 12 volts there, you can eliminate anything in the wiring before the coil as the problem.
#2. When you say it wouldn't run, do you mean it would turn over every time but just not start? Or do you mean it didn't even turn over (which would indicate a starter issue)? If it doesn't turn over at all, we need to look at potential starter wiring issues. If it turns over but just won't start, it's an ignition issue (coil, plugs etc.)
If the starter is not cranking on these failed start attempts, go under the rear seat with your multimeter and find the thick red wire going through a plastic connector block--this is your starter wire. Disconnect the ignition switch side of that wire from the block and check for 12 volts there when you turn the key to START. This will help determine whether it's the starter or the ignition switch.
#3. You have a 1974 body so I assume the wiring is 74 as well. On 74s they were factory wired with a seat belt interlock relay that acted as a starter inhibitor-- if the seat belt wasn't fastened the car wouldn't start. Lots of folks have bypassed this system by using a jumper. Check out this thread:
https://www.thesamba.com/vw/forum/viewtopic.php?p=7344474
About 3/4 of the way down the first page you'll see a post from ashman40 describing the seat belt interlock relay system and how to bypass it.
#4. You mention a condenser wire so I think I already know the answer to this, but are you by chance running an electronic ignition module in your distributor? You also mention a tach wire at the coil-- is this wire coming off the positive or negative side of the coil? Improperly wired tachometers can cause all sorts of headaches. In fact, just do me a favor and disconnect that tach wire completely from the coil and see if it makes any difference.
Hope some or all of this helps. If you can please post some photos of the engine bay (particularly the wiring around the coil) and up front around the fuse box area, that may help as well.
_________________
I'm the humblest guy on this board.
1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor |
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ashman40
Samba Member
Joined: February 16, 2007
Posts: 15982
Location: North Florida, USA
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| Posted: Sun Feb 10, 2019 7:23 pm Post subject: Re: Electrical nightmare |
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| JCockrill wrote: |
| So the basics of the car. 1974 beetle sedan engine and suspension. 1972 pan to match. New wiring harness placed in 2 years ago. |
Is the wiring harness for a '72 or '74??
| JCockrill wrote: |
... found some smoke and fried wire insulation at the coil.
<...>
Ran new wire from choke/carb (stock single carb) to igition coil. Found this was possible pinched and maybe grounded as insulation was burnt off. Pulled the condenser from the svda distributor and put on a new one as the wire was fried. Under the distributor dust cover I replaced the internal black insulated wire as it was fried. |
Exactly WHICH wires were melted?? The entire ignition coil circuit is NOT fuses and it powers multiple devices in addition to the ignition coil. From all your descriptions it sounds like the following wires melted:
black wire from ignition coil #15 to idle cutoff solenoid and choke coil.
condenser wire running from ignition coil #1 terminal to the distributor as well as the internal segment from the condenser to the points.
Any other wires??
When there is a short at the engine compartment there is often damage to the long wire run from the ignition switch to the ignition coil. You can't easily inspect this length since it is run inside the body and inside a sleeve.
| JCockrill wrote: |
INITIAL THOUGHTS:
Figured the stainless steel spark plug wires did not have a big enough gauge wire and it jumped to the coil. Dont hold me to this but that was my suspicion.
RAN NEW WIRES: Removed and got rid of the stainless steel spark plugs and replaced with the stock version from Jbugs. |
Spark from the ignition coil HT wires is high voltage but low amps. Amps is what melt wires. If the HV spark was jumping from the spark plug wire to the coil then your would experience bad ignition on some cylinders.
If this was your problem you would have been able to see sparks jumping off the plug wires at night with the lights off.
| JCockrill wrote: |
| Tach wire, reverse wire, and igition wire from igition switch seemed fine so left them all. |
Disconnect your tach wire. Once you get everything you can reconnect it. Same for reverse wire. Stick to the basics, eliminating things not required from the equation and troubleshoot with fewer variables.
| JCockrill wrote: |
TURN OVER RESULTS #1
Tried to turn over and as it did rotated I didnt get a spark. |
Just to confirm, you removed a spark plug wire from the spark plug and held it near a ground watching for a spark while someone cranked the engine? And while cranking you SAW no spark? Did you remove the center wire from the distributor cap and hold IT near ground while the engine was cranking? This is how you check for spark.
While you are doing this test, place a voltmeter on the #15 terminal of the ignition coil and confirm the voltage at the coil WHILE you are cranking the engine. The starter will draw a good deal of current. This can drop the voltage that makes it to the ignition coil WHILE the engine is cranking. If the voltage drops too much the coil can stop firing.
| JCockrill wrote: |
NEXT ATTEMPT
Ran a test wire from the igition switch to the coil just in case the wire was fried somewhere. No turn over. Direct wired it to a (h)ot lead in case it was the igition switch and no joy. Figured I would replace the coil just in case as I had one here new. Put the new coil in.
DISTRIBUTOR ATTEMPT
Pulled the distributor and put in the 009 I had from the original 74 engine. Checked and tried with the igition coil direct to a hot lead. BACKFIRE! I was hopeful. |
This is a BIG indicator that your SVDA distributor is bad. It is possible the short burnt the points.
| JCockrill wrote: |
| Cranked and it ran. It didnt have the SDVA so it had to be feathered but it ran. Was hopeful! Stopped the engine with the inline battery disconnect switch since the coil was direct wired to a hot lead and would not cut off with the igition switch. |
At idle the 009 and SVDA function the same. The difference is only the components (points + condenser and ground thru the distributor). Inspect your SVDA distributor and maybe replace the points and condenser. If the distributor has a ground wire between the points plate and the distributor body inspect it carfully.
| JCockrill wrote: |
Ran the original wire for the coil and tried again. No luck. Figured the wire was fried somewhere. Ran a new 16 gauge from coil, through body, and to the igition switch. Figured all was good.
MULTIMETER TRIES
So pull out the multimeter and got to work again.
Tried to narrow it down and i will spare you the details of every wire i checked for 3 hours.
<...>
I seem to be getting sporadic voltage to the coil. I ended up moving the coil wire back to a direct hot just to try to help in diagnosis. No joy still on getting it to run. |
This is where alligator clips come in handy. They provide a solid connection between your meter and the wires. You need to make sure whether the sporadic voltage is between your probe and the wiring or in the wiring. Anything less than CONSTANT voltage to the ignition coil means your engine will not run.
| JCockrill wrote: |
| Voltage on the battery was sitting at 12.2-12.5 and the starter runs fine. Figured that would eliminate the battery and the positive to the starter. Tested some of leads at the fuses. Headlights and ACC seem to have a good voltage around 11.6 from wire to the ground screw they are attached to. |
What is the voltage reading AT the ignition coil??
What is the voltage reading WHILE the engine is cranking? The ignition coil can stop firing completely if the voltage drops below 10v. Below 11v it can become unreliable.
| JCockrill wrote: |
| Checked ignition coil/ignition hot in from terminal to battery negative and it was good but in ny head wondering if this is constant. |
Check while you jiggle the ignition switch. When the ignition goes bad it can become VERY sensitive to position. As the engine runs and the keys jingle the voltage coming from an old switch can fluctuate greatly suggesting the contacts inside the ignition switch are burnt and only when the key is in the "sweet spot" does it provide voltage properly.
| JCockrill wrote: |
| Checked igition coil in on multimeter. Now it could be my meter or me finding a good ground but sometimes it would be 0 and some a good volt. New wire and all. |
DOn't just check the voltage that makes it to the ignition coil. Remove al the wires and test the resistance in the primary winding (#15 to #1 : should read 3-4ohms) and the secondary windings (center post to #1 : should read 5,000-8,000ohms). If the primary winding resistance is too low it can burn the points prematurely.
| JCockrill wrote: |
| Left battery on and igition in run and took a break to see if the coil would heat up. After 15 minutes it was hot. Turned off and then a few minutes turn all back on and tried to start. Still no joy. |
This is a very bad idea. If the points are closed, there is a direct path to ground for the ignition coil. This will over heat the coil. Most coil makers recommend turning OFF ignition switch if the engine is to be left not running for more than 5min. You may have damaged the coil or the points.
_________________
AshMan40
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'67 Beetle #1 {project car that never made it to the road  }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!} |
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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Sun Feb 10, 2019 7:26 pm Post subject: Re: Electrical nightmare |
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Thanks for the questions, SB001. Let me get a few over to you now
#1 - I moved it from the ignition plug on the ignition switch to the hot wire in. I just put a jump to attach the two together. I will run through the multimeter test tomorrow to check those spots and report back. I checked the front side of the infused 12volt and was getting a good 12 v there. I will need to check again at the ignition switch to make sure everything is good again. Checked so much today it is running together!
#2 - it would always turn over and the starter never had issues. I just couldn't get it to spark up and get the engine running by itself.
#3 - pulled the original wiring out and had one made by Mike at Dune Buggy Brothers. I will get a photo of the wiring harness diagram up tomorrow.
_________________
'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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sb001
Samba Member
Joined: May 19, 2011
Posts: 10406
Location: NW Arkansas
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| Posted: Sun Feb 10, 2019 9:22 pm Post subject: Re: Electrical nightmare |
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| JCockrill wrote: |
Thanks for the questions, SB001. Let me get a few over to you now
#1 - I moved it from the ignition plug on the ignition switch to the hot wire in. I just put a jump to attach the two together. I will run through the multimeter test tomorrow to check those spots and report back. I checked the front side of the infused 12volt and was getting a good 12 v there. |
As ashman sais in his post above this may have fried your coil or points in the distributor. If the points were in the closed position (i.e. touching each other) and you apply power to the coil it creates a constant grounded circuit through the coil and the points and they heat up and can burn up. The power circuit to the coil was NOT fused from the factory- it runs out of the ignition switch to the #11 fuse on the fuse box and then bridges over to #12 fuse and comes off the fuse box and goes to the coil--but it always stays on the UNFUSED side of the box. So there's no fuse to detect a current overload and pop. I doubt your new harness changed that setup. Not saying for sure that's what happened but it's a possibility.
| JCockrill wrote: |
| #2 - it would always turn over and the starter never had issues. I just couldn't get it to spark up and get the engine running by itself. |
Well this most likely elminates anything in the starter path as being a problem, so that's good.
| JCockrill wrote: |
| #3 - pulled the original wiring out and had one made by Mike at Dune Buggy Brothers. I will get a photo of the wiring harness diagram up tomorrow. |
Thanks this should help out some. I wonder if they somehow bypassed the seat belt interlock relay.
_________________
I'm the humblest guy on this board.
1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor |
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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Mon Feb 11, 2019 5:58 am Post subject: Re: Electrical nightmare |
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Will get some photos pointed today of everything. The distributor did work and the engine fired during the middle of this then quit working. I did leave it on and could of been 15 minutes or less. At the time I had no power going to it for some reason. When I checked it again it had volt and hot to the touch. If this distributor did burn points I am not that upset as I was going to go back go a vacuum advance. Hopefully it didnt though as an extra is always nice to have around.
Same for the fusing here. Power to starter then to ignition switch then out to the coil without a fuse. I added one during one of my runs for a 16 gauge at 20 amp fuse and it hasn't been burnt up yet. But for the purposes of testing I have been using the temp direct run wire just in case there is something I could have missed.
Down with a stomach bug this morning that a little one brought back from daycare which was nice of her to share 🤣
_________________
'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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ashman40
Samba Member
Joined: February 16, 2007
Posts: 15982
Location: North Florida, USA
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| Posted: Mon Feb 11, 2019 7:56 am Post subject: Re: Electrical nightmare |
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| JCockrill wrote: |
| At the time I had no power going to it for some reason. When I checked it again it had volt and hot to the touch. |
You need to investigate this. The coil #15 terminal should have constant 12v while the ignition switch is in the ON/RUN and START positions. If the voltage drops for even a second the engine can stall.
| JCockrill wrote: |
| If this distributor did burn points I am not that upset as I was going to go back go a vacuum advance. |
I would inspect/replace the points in the SVDA distributor before re-installing. Look for pitting at the point contacts. Reset the point gap. Use your MM an test for continuity between the condenser wire and the body of the distributor when the points are closed. Also test that when the points OPEN that continuity is lost. It seems more than coincidental that replacing your distributor got your engine running.
I also suggest that you rotate your engine until the rotor is pointing to the #1 spark plug wire position on your distributor cap BEFORE you remove the 009. Then, when you install the SVDA install the empty distributor cap and place the #1 plug wire over the tip of the rotor. The #1 plug wire position is different between the two distributors so don't expect you will be able to just remove the distributor cap w/ wires connected and snap it back onto the SVDA when installed. That will never work.
| JCockrill wrote: |
| Same for the fusing here. Power to starter then to ignition switch then out to the coil without a fuse. I added one during one of my runs for a 16 gauge at 20 amp fuse and it hasn't been burnt up yet. |
I don't understand what you mean by the underlined sentence above?? I'm wondering of you mean "Power to fuse box then to ignition switch and then out to the coil without a fuse." That would make more sense.
Adding a fuse just after the ignition switch is not a bad idea, just make sure it is sized correctly as the current load on this circuit can be rather high. 20A fuse may be barely enough depending where you put it.
| JCockrill wrote: |
| But for the purposes of testing I have been using the temp direct run wire just in case there is something I could have missed. |
This is good. Only after you have the ignition working as expected switch back to the ignition circuit. It wouldn't hurt to add an inline fuse to the temp wire... just in case. 
_________________
AshMan40
---------------------------
'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!} |
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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Mon Feb 11, 2019 8:45 am Post subject: Re: Electrical nightmare |
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Here are some details:
| Quote: |
sb001
#1. When you moved the coil wire to a hot lead, where EXACTLY did you move it to? |
Moved it to the hot wire from starter that was at the ignition switch
| Quote: |
| The coil gets its power from the ignition switch yes, but it comes off the fuse box. |
This harness gets unfused power. I will post the wiring diagram so you can see.
| Quote: |
| #2. When you say it wouldn't run, do you mean it would turn over every time but just not start? |
It would turn over so not the starter. I will check the ignition switch.
| Quote: |
#3. You have a 1974 body so I assume the wiring is 74 as well.
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I will post the new wiring diagram from Mike.
| Quote: |
| #4. You mention a condenser wire so I think I already know the answer to this, but are you by chance running an electronic ignition module in your distributor? |
I have a vacuum assist distributor and the original 009 distributor.
| Quote: |
| You also mention a tach wire at the coil-- is this wire coming off the positive or negative side of the coil? |
It is coming off the negative side. I will make sure to disconnect the tach before moving any further.
Ashman40
| Quote: |
Exactly WHICH wires were melted?? The entire ignition coil circuit is NOT fuses and it powers multiple devices in addition to the ignition coil. From all your descriptions it sounds like the following wires melted:
black wire from ignition coil #15 to idle cutoff solenoid and choke coil. condenser wire running from ignition coil #1 terminal to the distributor as well as the internal segment from the condenser to the points. Any other wires?? |
That is correct on all of these. No other wires that I have found yet.
| Quote: |
| When there is a short at the engine compartment there is often damage to the long wire run from the ignition switch to the ignition coil. You can't easily inspect this length since it is run inside the body and inside a sleeve. |
Truth. I have run a test wire new externally to test. #15 black wire. Used a 16 gauge wire.
| Quote: |
Spark from the ignition coil HT wires is high voltage but low amps. Amps is what melt wires. If the HV spark was jumping from the spark plug wire to the coil then your would experience bad ignition on some cylinders.
If this was your problem you would have been able to see sparks jumping off the plug wires at night with the lights off. |
I didn't have any bad ignition on the engine before it died. When I got it running temporarily It ran fine and seemed to be in tune. I have no idea what happened in the middle of the project to have it running then to have it not now - all in a span of a few hours.
| Quote: |
Just to confirm, you removed a spark plug wire from the spark plug and held it near a ground watching for a spark while someone cranked the engine? And while cranking you SAW no spark? Did you remove the center wire from the distributor cap and hold IT near ground while the engine was cranking? This is how you check for spark.
While you are doing this test, place a voltmeter on the #15 terminal of the ignition coil and confirm the voltage at the coil WHILE you are cranking the engine. The starter will draw a good deal of current. This can drop the voltage that makes it to the ignition coil WHILE the engine is cranking. If the voltage drops too much the coil can stop firing. |
The first time I pulled the plugs with the SVDA I had them grounded and, while the engine was started, I did not see a spark. When I flipped to the 009 and grounded the spark plugs I got a spark. I did not do it with the center wire. This is on my list to do and will follow up.
| Quote: |
| This is a BIG indicator that your SVDA distributor is bad. It is possible the short burnt the points. |
I will post photos of the distributor so let you see what I am seeing.
| Quote: |
What is the voltage reading AT the ignition coil??
What is the voltage reading WHILE the engine is cranking? The ignition coil can stop firing completely if the voltage drops below 10v. Below 11v it can become unreliable. |
I will check today and report. Any particular position you want the leads for this answer? Ignition coil positive in to center out? Center out to ground? Etc. I will get you all of these answers.
| Quote: |
| DOn't just check the voltage that makes it to the ignition coil. Remove al the wires and test the resistance in the primary winding (#15 to #1 : should read 3-4ohms) and the secondary windings (center post to #1 : should read 5,000-8,000ohms). If the primary winding resistance is too low it can burn the points prematurely. |
I will do this and report back
| Quote: |
| Use your MM an test for continuity between the condenser wire and the body of the distributor when the points are closed. Also test that when the points OPEN that continuity is lost. |
Will do this and report
I put some of my responses in bold so I know what information I owe back. Will find what I can and get back to you all. I thank you all for the help so far. Felt like I was banging my head against a wall!
_________________
'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Mon Feb 11, 2019 9:08 am Post subject: Re: Electrical nightmare |
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Here are the wiring diagrams as promised!
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'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Mon Feb 11, 2019 10:33 am Post subject: Re: Electrical nightmare |
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Ignition coil resistance test on completely disconnected coils
This is the blue Bosch I had on originally:
Positive to negative leads is showing 3.7.
Negative to hot side is checking at 8.26
New coil I changed to:
Positive to negative leads showing 3.7
Negative to center hot side is at 8.18
Condenser continuity test from green to points open and points closed
Lined up with number 3 firing getting .005
Off center test in between firing is .001
Getting close to the same results with the SVDA
Doing some voltage testing
Battery positive to starter in: 12.38
Starter positive to alternator: 12.22
Alternator positive in to ground: 12.28
Alternator out to ground (not running of course): 5.2
Jumped ahead here. Test wire from ignition switch power to ignition coil 12.5
Now to the ignition switch area:
Power in to the ignition switch checked against ground: 12.59
Coil positive out checked against ground with key off: 0. With key on: 12.6
Acc power lead against ground with key on: 12.63
I then flipped the test wire that was straight to power in at ignition switch and placed it on the ignition out of the ignition switch. Showed 12.5
Went back to the ignition coil and checked the test wire other end and showing 12.5 so the wire is good.
Now trying to video the coil center wire against ground to check for spark with one person is not easily done so not going to say I have good results. I did not see a spark in the video. I tried two different center wires I had and did not see spark. Now that could be user error but posting what I saw until I can get a second set of hands.
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'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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ashman40
Samba Member
Joined: February 16, 2007
Posts: 15982
Location: North Florida, USA
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| Posted: Mon Feb 11, 2019 10:48 am Post subject: Re: Electrical nightmare |
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| JCockrill wrote: |
| Quote: |
sb001
#1. When you moved the coil wire to a hot lead, where EXACTLY did you move it to? |
Moved it to the hot wire from starter that was at the ignition switch |
The wire at the ignition switch that runs to/from the starter is the red/black #50 wire. This wire only has power when the key is in the START position. This NOT a good source for constant/reliable 12v.
You can use one of the following for a good source of constant 12v+:
The B+ stud on the alternator (this is directly connected to the battery)
Battery positive (+) terminal at battery post
The white rectangular junction under the rear seat where three heay gauge red (or red/white) wires come together.
The INPUT side of #8 or #9 fuse at the fuse box
| JCockrill wrote: |
| Quote: |
| The coil gets its power from the ignition switch yes, but it comes off the fuse box. |
This harness gets unfused power. I will post the wiring diagram so you can see. |
I just saw you posted your wiring diagrams... you have a Dune Buggy 6-fuse fuse box with wiring harness. Forget anything about how wiring should run and the colors. Your harness is a "different beast".
In your diagram, the wire powering the ignition coil #15 does comes from the ignition switch. This not stock, but is correct for your wiring.
| JCockrill wrote: |
| Quote: |
| #2. When you say it wouldn't run, do you mean it would turn over every time but just not start? |
It would turn over so not the starter. I will check the ignition switch. |
Still confirm that there is 12v at the ignition coil #15 terminal WHILE the engine is cranking.
| JCockrill wrote: |
| Quote: |
| #4. You mention a condenser wire so I think I already know the answer to this, but are you by chance running an electronic ignition module in your distributor? |
I have a vacuum assist distributor and the original 009 distributor. |
sb001's question was whether you are running points on both distributors?
| JCockrill wrote: |
| Quote: |
Exactly WHICH wires were melted?? The entire ignition coil circuit is NOT fuses and it powers multiple devices in addition to the ignition coil. From all your descriptions it sounds like the following wires melted:
black wire from ignition coil #15 to idle cutoff solenoid and choke coil. condenser wire running from ignition coil #1 terminal to the distributor as well as the internal segment from the condenser to the points. Any other wires?? |
That is correct on all of these. No other wires that I have found yet. |
My concern is the wire running from the coil #1 to the points in the distributor. If you have the correct ignition coil it should have internal resistance of 3-4ohms. In normal use this level of resistance prevents enough current from flowing thru the coil to the points and melting the wire. That you actually melted the condenser wire tells me too much current flowed thru the wire. This suggests the internal resistance in the coil is too low... or the condenser wire was connected to the wrong side of the ignition coil.
| JCockrill wrote: |
| Quote: |
What is the voltage reading AT the ignition coil??
What is the voltage reading WHILE the engine is cranking? The ignition coil can stop firing completely if the voltage drops below 10v. Below 11v it can become unreliable. |
I will check today and report. Any particular position you want the leads for this answer? Ignition coil positive in to center out? Center out to ground? Etc. I will get you all of these answers. |
Place your COM (black) probe on ground and the red probe on the #15 (+)terminal of the ignition coil. Measure voltage with the key in the ON/RUN position and again when the key is in the START position.
_________________
AshMan40
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'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!} |
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sb001
Samba Member
Joined: May 19, 2011
Posts: 10406
Location: NW Arkansas
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| Posted: Mon Feb 11, 2019 11:13 am Post subject: Re: Electrical nightmare |
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One more quick question in addition to ashman's above-
Are you running a generator with an external voltage regulator (usually mounted under the rear seat driver's side) or are you running an alternator with an internal voltage regulator?
I ask because according to your wiring diagram above you have power to basically everything coming from the always hot "16w" wire coming off the starter going directly to the ignition switch. This will work but again is not stock- stock for your year had a wire coming off the + battery terminal going to the B+ on the voltage regulator under the rear seat and then up to the front of the car (first to the headlights, then over to the ignition switch, then out to the fuse box.)
I am just wondering whether that initial power path has been bypassed.
Just a curiosity question more than anything else.
_________________
I'm the humblest guy on this board.
1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor |
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ashman40
Samba Member
Joined: February 16, 2007
Posts: 15982
Location: North Florida, USA
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| Posted: Mon Feb 11, 2019 11:16 am Post subject: Re: Electrical nightmare |
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Didn't see the below before I posted my last reply...
| JCockrill wrote: |
Ignition coil resistance test on completely disconnected coils
This is the blue Bosch I had on originally:
Positive to negative leads is showing 3.7. GOOD
Negative to hot side is checking at 8.26 Did you mean 8.26Kohms (8,260ohms)?? If so, GOOD
New coil I changed to:
Positive to negative leads showing 3.7
Negative to center hot side is at 8.18 Did you mean 8.18Kohms (8,180ohms)?? If so, GOOD |
| JCockrill wrote: |
Condenser continuity test from green to points open and points closed
Lined up with number 3 firing getting .005
Off center test in between firing is .001
Getting close to the same results with the SVDA |
I think you misunderstood the purpose of this test??
The points are a simple switch for the green condenser wire. When the point contacts are CLOSED there should be continuity (zero resistance) between the end of the loose green wire and the body of the distributor.
When the points are OPEN there should be INFINITE resistance between the end of the wire and ground.
Rotate the crank (or just the shaft if the distributor is out of the engine) and watch as the points OPEN/CLOSE making sure the resistance thru the wire changes as the points OPEN/CLOSE.
If the resistance in the wire is always close to zero then the points are bad and will never fire the ignition coil.
| JCockrill wrote: |
Doing some voltage testing
Battery positive to starter in: 12.38
Starter positive to alternator: 12.22
Alternator positive in to ground: 12.28
Jumped ahead here. Test wire from ignition switch power to ignition coil 12.5 |
The numbers above look okay, but it seems off that the voltage reading at the end of the battery cable is only 12.38v when the voltage at the ignition coil is 12.5v?? Why is it higher? It suggests high resistance in the battery cable?
| JCockrill wrote: |
| Alternator out to ground (not running of course): 5.2 |
I'm assuming by "alternator out" you mean the D+ terminal on the alternator? While the alternator is NOT spinning, this wire should be grounded. It might show a small voltage (less than 1.0v) but 5.2v on the D+ wire is TOO much. It suggests a short inside the alternator.
| JCockrill wrote: |
Now to the ignition switch area:
Power in to the ignition switch checked against ground: 12.59
Coil positive out checked against ground with key off: 0. With key on: 12.6
Acc power lead against ground with key on: 12.63
I then flipped the test wire that was straight to power in at ignition switch and placed it on the ignition out of the ignition switch. Showed 12.5
Went back to the ignition coil and checked the test wire other end and showing 12.5 so the wire is good. |
All of the above sounds reasonable/acceptable. Again you have a higher voltage reading down the length of wire.
| JCockrill wrote: |
| Now trying to video the coil center wire against ground to check for spark with one person is not easily done so not going to say I have good results. I did not see a spark in the video. I tried two different center wires I had and did not see spark. Now that could be user error but posting what I saw until I can get a second set of hands. |
Disconnect the center distributor cap wire from the cap and hold it close to ground (1-2mm from ground) while cranking.
Lacking an assistant, run a jumper wire to the #50 terminal on the starter solenoid. Some solenoids have 2 #5 terminals. Run the loose end of the wire to the engine compartment.
With your car in neutral and parking brake set, touch the loose #50 wire to a constant 12v source and the engine should crank. This is a "poor man's" starter bump switch.
_________________
AshMan40
---------------------------
'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!} |
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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Mon Feb 11, 2019 5:12 pm Post subject: Re: Electrical nightmare |
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Will get the distributor tested again tomorrow. I misunderstood and get what you are asking for now.
It should like a possible cause is the ignition switch. I will test the wires while cranking it to see what voltage I am getting. Will test at the ignition switch itself and at the coil 15+.
I will also retest the alternator. If I have a short in it now would be the time to replace it. If I am doing that I am going to replace the fan also as I am getting some rubbing.
And just for the record I am still not sure what is happening so going to keep working the problem until we have it down! I am just hopeful it turns out to be a switch and the worlds problems are solved!
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'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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JCockrill
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Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Fri Feb 15, 2019 6:28 pm Post subject: Re: Electrical nightmare |
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Getting over this bug I caught and starting to diagnose again (get it? Bug? Insert eye roll at Dad joke now)
For the purposes of this test I had my wife turning the engine over with the key in the ignition. No bump switch so results are the same as a regular day driving this 74.
Pulled the center wire at distributor and left connected to the coil on the other end. Held the bare end to a ground and turned over to start. No spark. Same results twice.
Tested the coil #15 wire at the ignition coil (connected to the coil and connected to the coil out at ignition switch) before start with key in on position. It was showing at 12.3 / 12.5. Tested twice with same results.
Tested coil 15 at ignition (same set up as above) during a start attempt and it dropped to almost nothing. Talking 0.8. Tested twice with same results.
Tested at the ignition switch out to coil 15 wire. Key off was running 0.5 or so. Small leak over.
Tested at ignition switch with key on but not starting. Running voltage at 12.3/12.5. Got the same results twice.
Tested at ignition switch with while attempting to start. Voltage dropped to 0.5 to 0.8. Same results twice.
Unless I am missing something it sounds like a fried ignition switch.
If I can get it running I am thinking the next will be to test the alternator as it sounds like that has a cross in it somewhere, correct?
Sorry for the few days but I was down and out!
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'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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sb001
Samba Member
Joined: May 19, 2011
Posts: 10406
Location: NW Arkansas
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| Posted: Fri Feb 15, 2019 9:24 pm Post subject: Re: Electrical nightmare |
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| JCockrill wrote: |
Tested the coil #15 wire at the ignition coil (connected to the coil and connected to the coil out at ignition switch) before start with key in on position. It was showing at 12.3 / 12.5. Tested twice with same results.
Tested coil 15 at ignition (same set up as above) during a start attempt and it dropped to almost nothing. Talking 0.8. Tested twice with same results.
Tested at the ignition switch out to coil 15 wire. Key off was running 0.5 or so. Small leak over.
Tested at ignition switch with key on but not starting. Running voltage at 12.3/12.5. Got the same results twice.
Tested at ignition switch with while attempting to start. Voltage dropped to 0.5 to 0.8. Same results twice.
Unless I am missing something it sounds like a fried ignition switch.
If I can get it running I am thinking the next will be to test the alternator as it sounds like that has a cross in it somewhere, correct?
Sorry for the few days but I was down and out! |
BINGO. I think you just isolated the problem.
Yes your ignition switch does seem to be malfunctioning. With the key in the START position, you should be getting 12 volts out BOTH the coil wire and the starter wire. But you say when you turn the key to the START position the voltage out the coil wire drops to almost nothing. This indicates a malfunction inside the ignition switch, where the rotating conductor inside the switch is not providing power from the hot 12 volt input from the battery through to both the 15 (coil) output AND the 50 (starter) output at the same time.
Take a look at this photo from one of ashman's other threads:
This shows the inner ignition switch terminals with the rotating conductor (that bridges power from that center battery terminal out to the perimeter terminals) removed.
Now take a look at this photo:
This picture shows the inner part of the ignition switch with the Y-shaped rotating conductor installed and in the "START" position. Note that it is bridging power from that central battery terminal out to BOTH the 15 (coil) and the 50 (starter) terminals.
Now here is a picture of the switch in the ON position:
Note that in the ON position the right hand "tong" of the Y-shaped conductor is providing power to the 15 terminal, but in the START position the left hand "tong" is providing power to the 15 terminal.
So it looks like what has happened might be that the conductor's left hand "tong" has bent out of shape or position a bit, so when you are turning your key to the START position, it is out of whack and not touching the 15 terminal.
You can certainly order another ignition switch or if you feel up to it you might try removing your existing switch, disassembling it, and seeing if you can simply bend that tong back to its proper position. (Worst that can happen is it's unfixable and you end up ordering a new switch anyway!)
BTW here is ashman's thread on the ignition switch that I borrowed those photos from:
https://www.thesamba.com/vw/forum/viewtopic.php?t=455734
Definitely worth a read if you decide to try to tackle repairing the switch. Good luck!
_________________
I'm the humblest guy on this board.
1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor |
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JCockrill
Samba Member
Joined: January 14, 2016
Posts: 33
Location: Charleston, SC
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| Posted: Sun Feb 17, 2019 6:20 pm Post subject: Re: Electrical nightmare |
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New ignition switch will be here Tuesday, Feb. 19, 2019. I will post and let you know if this solves it.
If it does I will move on to the alternator short we were talking about earlier.
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'15 Manxter on a '72 pan with '74 engine/trans/and axles. Just trying to work out the gremlins in the build |
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ashman40
Samba Member
Joined: February 16, 2007
Posts: 15982
Location: North Florida, USA
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| Posted: Mon Feb 18, 2019 10:46 pm Post subject: Re: Electrical nightmare |
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I would make one comment re: the test results you had with your ignition switch....
Did you confirm the circuit you have running to the ignition coil is the #15 circuit from the ignition switch? A common problem is someone will use the X circuit of the ignition switch in place of the #15 circuit. BOTH have 12v when in the ON/RUN position but when the switch is turned to the START position only the #15 continues to have 12v. The X circuit looses voltage as a means of freeing up current for non-critical systems. So when someone incorrectly uses the X circuit to power the ignition coil they run into the problem of the engine cranking but wont start. Sometimes the engine will start just as you release the ignition switch and it returns to the ON/RUN position while the engine is still rotating.
Check if your ignition switch has an X terminal (black/yellow wire). Make sure you are not using it.
If you are indeed using the #15 terminal (back wire) then your switch has gone bad internally and buying a new one is the correct solution.
NOTE: in that thread about the ignition switch internals, I noted that the contacts in the newer AFTERMARKET ignition switches were much smaller than the OG switches and you might consider adding a relay as a means of reducing the current flow thru the ignition switch as a means of extending the life of the switch. The Hard Start Relay is commonly added to the starter solenoid circuit (#50), but I also feel there is enough current flowing thru the #15 circuit that it too could benefit with a relay. This relay should be placed immediately after the ignition switch to avoid problems.
_________________
AshMan40
---------------------------
'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!} |
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