'66 Beetle +6V starting problem

[srw_bug]

I have restored my '66 beetle sedan and left it stock 6v for now, but having second thoughts because of a starting problem.

My parents had this beetle shipped new from Germany when they came back to the states after military service. They drove a different beetle while they were stationed there but wanted a new one when they left and came back to the states.

I learned to drive using this bug back in 1976 back in Nebraska and drove it every day until around 1987 when I got a new car with air conditioning for the Texas heat. It has been sitting in the elements in Texas ever since. After getting the kids through college and with their encouragement I finally got around to restoring it to its former glory with there help. Started the rebuilding process back in 2017 and had it finished in 2018. Can't take any credit for the body work or paint job, that was done by McGee's Customs out of Dallas. Even took it to a North Texas Dub Splash bug show in 2018.

Here is my problem, the engine turns over just fine (sluggish at times) but does not start. The beetle runs fine after push starting it with no issues. During the restoration the carburetor was rebuilt (not by me) and had a generator and starter replaced as well. Have been through several starters and batteries trying to resolve this issue. I have replaced the entire wiring harness and did see overall improvement but, it did not fix the problem. Replaced both battery terminal wires and have a hard start relay in place. Replaced the ground strap from transmission to the engine as well. Almost all of my replacements parts have come from WW.

The generator puts out a good +7.2v after getting it replaced and had a new voltage regulator put in as well. The ignition coil seems to work fine, have new spark plugs and wires, condenser and points. All this was done during the restoration process.

Even after I drive it around for 30 minutes and pull it into the driveway and turn it off, it does not want to restart. It seems like it is getting flooded and not wanting to start back up. The starter motor turns the engine but it does not fire up. Sometimes it turns the engine a little slow like it is in molasses.

I have been reading through the forums about starting problems and applying what I have learned but nothing seems to fix the problem.
This has me stumped and has kept me from driving it.
Any help would be appreciated.

[ashman40]

Check the voltage at the battery terminals. I believe a fully charged 6v battery should read 6.3v when fully charged.

Place a VM on the ignition coil #15 (+) terminal and measure the voltage that makes it to the terminal when the ignition switch is turn to the ON/RUN position. Any difference between this and the battery voltage is likely due to wire resistance. A loss of 0.2v would be understandable.

Have a buddy crank the engine while you measure the voltage at the ignition coil #15 (+) terminal. You should expect the voltage to drop some as the starter motor pulls current from the battery, but if the voltage drops too much there is no longer enough current available for the coil to spark properly. I don't know what the min coil voltage is for a 6v coil.

Here is a test to see if it is a coil voltage problem...
Using your battery jumper cables connected to the battery (+) terminal extend the cable to the rear of the car. Wire a jumper wire between the jumper cables and the ignition coil #15 (+) terminal. Now the coil is powered directly from the battery with max current. Start the engine and see if your problem goes away. Disconnect the jumper wire and retest and confirm the problem returns.
Once you determine that lack of current/voltage at the coil is your issue you can take steps to improve the current that makes it to the coil. Cleaning the wire connections between the battery, the VR, the headlights switch, the ignition switch, fuse box and ignition coil can improve the current that makes it to the coil.
As a last ditch effort you could add a relay to the #15 wire in the engine compartment. This functions like the HSR relay for the starter circuit. This solution has a possible side effect of not being able to shutoff the engine with the key. To fix this you may need to add a diode to the #61 VR blue wire. Disconnect the blue #61 wire and if the engine turns OFF normally with the key you know you need to add a cheap 1A diode to the wire.
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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!}

[iowegian]

Ashman is spot on.
I had the same problem on my 6 volt '66. Simply stated, there was enough electricity to crank the engine nicely, but not enough left over to make the coil happy. Cleaning terminals cured it.

[Eric&Barb]

Congrats on your first post, and that looks like a really nice beetle!!!!

Always best to try a search first! Here just below is a search of just the 1958-67 beetle forum for "Starting Problem": Hover your mouse cursor over the "Forum" button above and in the pop up list that pops up is the "Search" feature you just left click on.

https://www.thesamba.com/vw/forum/search.php?searc..._chars=200

Lots of good info there!! If you do a search with a few different versions of the quire (EG Starter Problem, No Start, etc.) and still get no luck, then try just posting a question in the forum.

You need to make sure how much voltage is getting thru the electrical system while it is under a load. Using a spare sealed beam headlight bulb works well.

If you find that you have 7.5 volt at the battery, but only 6.5 or 5.5, etc. at various points like the wire at the starter solenoid, then you have a voltage drop/s in the electrical system. We have been able to get voltage drops in our old buses down to less than 1/10 of a volt.

Not only do you need the wiring connections to be clean of dirt and corrosion, but also tight. Use a little dielectric grease in each connection keeps out oxygen and water from corroding up the connections for a decade or more. SAME FOR THE GROUNDS!!! If the surfaces of the starter and transaxle where they mount together are corroded up or painted over there will be a problem with electrically grounding there. Same for the starter solenoid to starter body! Lots of other grounding points that need attention also not mentioned here.

Fuse box is another electrical problem for voltage drops. Have seen some that got so bad that the resistance cause so much heat as to melt the fuse box. The electrical clips in each slot of the fuse box are shoved in there loosely. VW finally for the 1968 model year spot welded each set of clips together to avoid this. Try a search of the 1958-67 beetle forum for "Fuse Box Soldering" with "Eric&Barb" as the author, and check mark the "Search topic title and message text" box.

Others here will insist on you just installing a starter relay to solve your starting problem. Problem with this is a relay will leave the rest of your electrical system with dim headlights & signals, slow wiper, and perhaps a horn that will not work with both the wipers and headlights turned on. BTDT! So best to go thru the entire electrical system first to get it all working better than factory.

Do post an image of the battery with the battery cable connected up!
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In Stereo, Where Available!

[GasBuggy]

You might be a good candidate for the 8V tractor battery swap and voltage regulator adjustment.

[heimlich]

That's a nice looking car.
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