Author |
Message |
RCJH77 Samba Member
Joined: March 27, 2022 Posts: 228 Location: Johnson County, KS
|
Posted: Wed Apr 24, 2024 7:21 am Post subject: Power drop and stall |
|
|
I know there are a lot of posts about similar issues, but none of the ones I've seen seem to match what I'm dealing with. I want to lay out my specific scenario and see if there's a consensus on what the issue is.
The issue:
I took my 6v 1960 Beetle out a couple days ago. It was running perfectly. Drove a few miles, turned it off for about 10 minutes, then started making my way back home. Still running perfectly, I'm running at 40-45 mph in 3rd gear for a minute or two when all of a sudden the engine shuts off. I noticed no loss of power prior. I came to a stop and tried to start it several times, but all it would do is crank.
I left it untouched for a few minutes and tried it again. This time is started up and seemed to be fine. I got back on the road and drove about a block before I noticed a power drop. I downshifted to 2nd and started to turn a corner and it stalled again. Same thing. Cranked, but wouldn't start. I decided to tow it home from there.
Additional context:
- I replaced the coil in August of last year. Not a $70 coil, but a new coil nonetheless. It was a $17 coil from Advance Auto.
- Within the last maybe 4-5 months, I've rebuilt the carb and fuel pump and they've been doing great since. At the same time, I de-rusted the tank and have confirmed that it hasn't started rusting again. I also put a new fuel filter on and it's pretty clear.
- Within the last year, I replaced the spark plugs.
- The battery doesn't seem to be an issue, but I haven't tested it other than knowing it still starts the car without any trouble.
- Last weekend, I replaced the fuel line. There are no leaks and the car seemed to be absolutely thriving with the new line (maybe my imagination).
- There was plenty of fuel in the tank and I confirmed last night that the fuel lever (to the tap) is installed correctly.
So a lot of what I'm seeing on other people's posts is "your fuel pump could be dirty" or "your coil could be bad" or "you need to clean your gas tank and blow out your fuel line." Considering everything I listed above, the only thing that makes sense to me is maybe the coil is junk and gave out. Everything else has been addressed pretty recently.
What do you all think?
[EDIT: May not matter, but this is a stock 1200 36hp motor.]
Last edited by RCJH77 on Thu May 30, 2024 4:42 am; edited 2 times in total |
|
Back to top |
|
|
RCJH77 Samba Member
Joined: March 27, 2022 Posts: 228 Location: Johnson County, KS
|
Posted: Wed Apr 24, 2024 8:14 am Post subject: Re: Power drop and stall |
|
|
Another thing I should mention is that I just adjusted the valves about 2-3 weeks ago. Saw a significant improvement in performance after that. |
|
Back to top |
|
|
klroger Samba Member
Joined: September 22, 2017 Posts: 155 Location: deep river, Ottawa Valley
|
Posted: Wed Apr 24, 2024 9:16 am Post subject: Re: Power drop and stall |
|
|
You may have a condenser going bad or the gap on the points are almost closed up. As soon as it quits, leave the key on, pull the coil wire from the cap & check for spark. You could rotate the engine by hand to do this, but you may feel safer using a buddy to crank it. Try to use the coil bracket as the ground for testing . Just thoughts... _________________ I Didn't know what to do, So I Didn't do anything!!!! |
|
Back to top |
|
|
Jeff Geisen Samba Chaplain
Joined: December 21, 2004 Posts: 1912 Location: N.W. Georgia
|
Posted: Wed Apr 24, 2024 7:07 pm Post subject: Re: Power drop and stall |
|
|
Nothing works like swapping in known good parts, one part at a time. _________________ I Corinthians 4: 1 thru 5
‘63 ragtop - ‘68 single cab |
|
Back to top |
|
|
Zwitterkafer Samba Member
Joined: November 17, 2007 Posts: 929 Location: Lanark County, Ontario, Canada
|
Posted: Thu Apr 25, 2024 1:41 pm Post subject: Re: Power drop and stall |
|
|
Had same symptoms last Spring, with an Indigo Blau 6V 36hp 1960 Beetle. The holes in the fuel tap selector gasket had swollen almost completely closed after winter storage. After a fuel tap rebuild it was perfect again. Agree with klroger too...points closing up could also do this. The points plate ground strap must be good, and the points wire feedthrough bolt must be properly insulated from the distributor housing. _________________ "Criticism comes easier than Craftsmanship"
- Zeuxius, 400 BC |
|
Back to top |
|
|
mukluk Samba Member
Joined: October 18, 2012 Posts: 7111 Location: Clyde, TX
|
Posted: Fri Apr 26, 2024 5:19 pm Post subject: Re: Power drop and stall |
|
|
Check the basics: verify valve clearances are good, look for loose wire connections at the coil and distributor, check for spark from the coil to the distributor and from the distributor to a spark plug, see if there's gas in the carb float bowl, and make sure the carb isn't overflowing/flooding.
The engine needs air, fuel, spark, and compression to fun. Start by narrowing down which one is lacking. _________________ 1960 Ragtop w/Semaphores "Inga" |
|
Back to top |
|
|
hertz Samba Member
Joined: March 19, 2006 Posts: 21 Location: Melbourne Australia.
|
Posted: Mon Apr 29, 2024 3:20 am Post subject: Re: Power drop and stall |
|
|
Check that your valves are actually opened
Mine had these exact same symptoms recently and then finally stopped. It was a stripped cam gear |
|
Back to top |
|
|
hertz Samba Member
Joined: March 19, 2006 Posts: 21 Location: Melbourne Australia.
|
Posted: Mon Apr 29, 2024 3:20 am Post subject: Re: Power drop and stall |
|
|
Check that your valves are actually opened
Mine had these exact same symptoms recently and then finally stopped. It was a stripped cam gear |
|
Back to top |
|
|
RCJH77 Samba Member
Joined: March 27, 2022 Posts: 228 Location: Johnson County, KS
|
Posted: Mon Apr 29, 2024 2:13 pm Post subject: Re: Power drop and stall |
|
|
Appreciate all the suggestions! Planning on working on it this weekend. I'll report back on what I figure out. |
|
Back to top |
|
|
Jeff O Samba Member
Joined: August 01, 2023 Posts: 11
|
Posted: Tue Apr 30, 2024 9:02 pm Post subject: Re: Power drop and stall |
|
|
Had similar problem with my '60 last year. My issue was also the reserve fuel tap, as already suggested. Try (gently) blowing air back up the full line to see if it blows freely back into the tank .
Careful if you take the valve apart. It's under spring pressure. |
|
Back to top |
|
|
08west Samba Member
Joined: June 26, 2013 Posts: 7 Location: Tyne & Wear, UK
|
Posted: Mon May 06, 2024 11:52 am Post subject: Re: Power drop and stall |
|
|
I had a similar problem in my 1200 '65 - drove a few miles then died. Turned out to be the fuel pump (original Pierburg). Put a clear PVC tube from pump to carb, and it could barely lift fuel up to the carb, never mind any pressure. The diaphragm wasn't split, but had gone sort of baggy around the edges. I blame the ethanol fuel we're forced to use in the UK now. Anyway, got a rebuild kit from WW (with Effbe diaphragm material - apparently ok with ethanol) and did a thorough rebuild, no problems since. |
|
Back to top |
|
|
RCJH77 Samba Member
Joined: March 27, 2022 Posts: 228 Location: Johnson County, KS
|
Posted: Sat May 25, 2024 2:30 pm Post subject: Re: Power drop and stall |
|
|
Finally got back to this after being sick for a couple of weeks. Here's everything that I've done.
- Adjusted the points and installed a new condenser (Advance Auto) - Cranks, won't start
- Installed new points (adjusted properly) and (another) new condenser (Wolfsburg West) - Cranks, won't start
- Installed new coil (the previous coil is less than a year old) - Cranks, won't start
- Checked the valves. Most of them were still set correctly, but three of them were completely closed. Couldn't even get the feeler gauge to slide through. Strange, considering the fact that I just adjusted them a couple months ago and the car ran better than ever. I went ahead and readjusted them. - Cranks, won't start
- Confirmed that the fuel tap and fuel tap lever are installed correctly
- Checked fuel filter under the car near the motor and it barely had fuel in it
- Pumped the gas pedal more and now the fuel filter seemed to be full - Cranks, won't start
- Opened up the top of the carburetor to see if the float was stuck and found that it was bone dry.
- Disconnected the fuel line going to the fuel pump and fuel dripped out.
- Disconnected the fuel line between the fuel pump and the carb and it was dry.
I figured the next step would be to work on the fuel pump, but I rebuilt it less than a year ago and it's performed flawlessly, so I stopped myself from tearing it apart and went to the Bentley manual. In the troubleshooting section, it essentially says that if the engine isn't getting fuel, then the valves are sticking and need to be serviced.
I don't mind rebuilding the fuel pump again, but the fact that those three valves were closed (i.e. couldn't get the feeler gauge through) is the part that concerns me. When I adjusted them a couple of months ago, I was meticulous about it. I'm 100% certain I did not over-tighten any of them and after tightening each nut, I confirmed that the feeler gauge still felt right sliding through. Again, the car ran better than ever after that.
Does it make any sense that the car would go from running perfectly, to just stopping at 45mph due to sticky valves? Wouldn't I have noticed some performance decline before that? |
|
Back to top |
|
|
RCJH77 Samba Member
Joined: March 27, 2022 Posts: 228 Location: Johnson County, KS
|
Posted: Sat May 25, 2024 6:04 pm Post subject: Re: Power drop and stall |
|
|
It's alive!!
So I pulled the fuel pump and was about to tear it apart when I tested the pump and nothing came out. Pushed it a few more times and some fuel shot out. Reinstalled it, then disconnected the line at the carb and put it in a clear bottle. Cranked the motor a few times while pumping the gas. Fuel eventually got to the bottle, so I reconnected the line to the carb, pumped the gas (a lot) and it fired up. Let it run for a little while, shut it off and let it sit for 10 min or so, then tried it again. Started right up.
I'll get it out tomorrow and drive it to see if the symptoms return, but so far this is the best result in 33 days. |
|
Back to top |
|
|
RCJH77 Samba Member
Joined: March 27, 2022 Posts: 228 Location: Johnson County, KS
|
Posted: Tue May 28, 2024 2:27 pm Post subject: Re: Power drop and stall |
|
|
Went for a 20-30 minute drive last night. No issues. Stuck fuel pump? Is that even a thing? Anyway, it seems to be back in running order.
Thanks for all the suggestions! |
|
Back to top |
|
|
67rustavenger Samba Member
Joined: February 24, 2015 Posts: 10220 Location: Oregon
|
Posted: Tue May 28, 2024 8:22 pm Post subject: Re: Power drop and stall [RESOLVED] |
|
|
Good job!
I had a fuel pump that wouldn't pump. It had lost it's prime.
I used a small squirt bottle to pump some gas into the pump outlet with the carb hose connected, turned the key. It pumped fuel right away. _________________ I have learned over the years.
Cheap parts are gonna disappoint you.
Buy Once, Cry Once!
There's never enough time to do it right the first time. But there's always enough time to do it thrice.
GFY's Xevin and VW_Jimbo! |
|
Back to top |
|
|
RCJH77 Samba Member
Joined: March 27, 2022 Posts: 228 Location: Johnson County, KS
|
Posted: Thu May 30, 2024 4:48 am Post subject: Re: Power drop and stall |
|
|
I spoke too soon. The problem is back. After driving it with no issues on a few separate trips, I'm driving it yesterday, going about 40mph, it starts to lose power and then dies. Got it restarted for about 5 seconds and it died again and had to be towed home.
I guess it's time to disassemble the fuel pump and see what's going on. |
|
Back to top |
|
|
VW_Jimbo Samba Member
Joined: May 22, 2016 Posts: 10493 Location: Huntington Beach, CA
|
Posted: Thu May 30, 2024 8:15 am Post subject: Re: Power drop and stall |
|
|
There was a time when the phenolic base would swell up and pinch the push rod. Might be worth the time, after you are on the side of the road, to remove the pump and see if the rod can move.
The swelling occurred with the heat cycle. So, once pulled over and allowed to cool down, the car would run till the base was hot enough to pinch the rod once again! _________________ Jimbo
There is never enough time to do it right the first time, but all the time necessary the second time!
TDCTDI wrote: |
Basically, a whole bunch of fuckery to achieve a look. |
67rustavenger wrote: |
GFY's Xevin and VW_Jimbo! |
|
|
Back to top |
|
|
RCJH77 Samba Member
Joined: March 27, 2022 Posts: 228 Location: Johnson County, KS
|
Posted: Thu May 30, 2024 9:03 am Post subject: Re: Power drop and stall |
|
|
VW_Jimbo wrote: |
There was a time when the phenolic base would swell up and pinch the push rod. Might be worth the time, after you are on the side of the road, to remove the pump and see if the rod can move.
The swelling occurred with the heat cycle. So, once pulled over and allowed to cool down, the car would run till the base was hot enough to pinch the rod once again! |
This is essentially a "vapor lock" right? I just saw a video on this issue about 5 minutes ago, but it was on a later model that has the rod that runs vertically. I wasn't sure if this happens on the earlier models or not. They recommended sanding down the outside of the flange that holds the rod in place, but I think the flange on mine isn't conducive to that process.
Link
|
|
Back to top |
|
|
EVfun Samba Member
Joined: April 01, 2012 Posts: 5751 Location: Seattle
|
Posted: Thu May 30, 2024 9:58 am Post subject: Re: Power drop and stall |
|
|
I had one tricky fuel pump. The vehicle would run just fine, then die. No about of cranking would get it to fire up, but if you waited anywhere between 5 and 30 minutes it would start again as if there never was a problem. The time between this happening could be twice in a day, or once every other week.
After determining that the engine died due to a lack of fuel (the accelerator pump didn't squirt more than once when this happened) I decided to check out the fuel pump. There are 2 little valves in a fuel pump. Those little plate valves had a small spring behind them to encourage them to close, except that spring was missing from one of the valves. The fuel flow must have kept it working normally, but it looked like it may have occasionally gotten tipped partly sideways in its cage and not been able to seal. A quick trip to the wrecking yard for a junk fuel pump to get that valve and the car was running fine all the time (until I blew the engine, but that is a whole 'nother tail of bad teenage driving). _________________
Wildthings wrote: |
As a general rule, cheap parts are the most expensive parts you can buy. |
|
|
Back to top |
|
|
rcooled Samba Member
Joined: September 20, 2008 Posts: 2613 Location: Santa Cruz, CA
|
Posted: Thu May 30, 2024 10:39 am Post subject: Re: Power drop and stall |
|
|
Check to make sure that the fuel tank's vent hose is clear. If the tank isn't vented to atmosphere and the cap seal is tight, a vacuum will develop in the tank after driving for a while and make it harder for fuel to flow back to the motor. _________________ '63 Ragtop (current)
'65 Ghia coupe (totaled)
'67 Ghia convertible (current)
'69.5 Ghia convertible and
'62, '63, '65, '69 Bugs (all long gone) |
|
Back to top |
|
|
|