Car stalling inadvertently while driving

[70_clementine_vert]

My 70 vert has been stalling the past few days. It doesn't want to start on occasion, But after about three tries I rev it up and she comes alive. Felt initially like fuel starvation but it happens infrequently. Checked the 'fire hazard' fuel filter in the engine compartment. Seems fine. In the past I have kept my 30/31 pict carburetor tuned up. It could be something there.

However, the way it suddenly stops, (to which I roll off the road and restart) it almost feels like it is an electrical problem. Possibly the coil, generator or plugs. would a bad coil give out like that or if it goes bad would it completely not start?

I have been using it as a daily driver for over 5 years and it has been GREAT. Usually I can quickly find the problem and adjust what needs to be adjusted but I wanted to see if anyone has some insight.

Thanks!
_________________
"In any moment of decision the best thing you can do is the right thing, the next best thing is the wrong thing, and the worst thing you can do is nothing."
Roosevelt, T.R.

[jinx758]

Howdy ..

I scrape ALL major grounds twice a year.

Verify 12 volts at coil (careful to not leave ignition on very long).
I disconnect wire & clip it out of the way in a safe manner, then test.

Almost sounds like an ignition switch, condenser, or maybe fuel pump.

"Looks good" is not an accurate diagnosis.

Best luck ... stay safe

jinx
_________________
" It's not valuable unless you learn something from an experience. " Henry Ford

It's not unlike the same difference

You can't push a rope


VALVES (cold)
POINTS
TIMING
CARB (fully warmed engine)

SCRAPE ALL GROUNDS

My Craigslist rescued 100 footer :
1971 Standard Bug
1776cc dual port
034 distributor
38mm EGAS Carburetor

[70_clementine_vert]

[Cusser]

[sb001]

[Starbucket]

Run a jumper wire from the battery pos. to coil pos and start the car with the key and see if the problem goes away= bad ign. switch (electrical part). Remove jumper to stop the motor.

[vamram]

Anyone for a bad coil? I've had blue coils and Craptronix Flame Thrower coils go bad. I'd be cruising all happy on the highway or elsewhere and suddenly the car would just die, not sputtering like fuel starvation, just it would turn off, alt and oil light would come on. Roll to the side of the road, wait a couple of minutes, it would start back up.
_________________
Eventually, "we are what we pretend to be.’”
Give peace a chance - Stop Russian-Soviet Aggression!!

'74 Super 9/16 - present, in refurb process.
'73 Super - 6/18 - Present - Daily Driver!
'75 Super Le Grande...waiting it's turn in line behind '74.
Click to view image
Save the Supers!!

[ashman40]

[70_clementine_vert]

Love this community and the help and learning that can happen here. So I took an old blue Bosch coil, an extra fuel pump and some wire with alligator clips to where I left my car to figure this out. The first thing I did was the easiest to try. Jump a wire from the coil positive to the battery positive like Starbucket said. I knew that the positive post on the generator went to the positive on the battery so I clipped in there. As soon as I turned the key it fired right up and like you said, I turned the ignition off and the car kept running. I was going to drive it home with the key out when I realized I would not be able to turn the steering wheel as it would lock. Genius I know. Put the key in and turned it one click and drove my car home.

[Eric&Barb]

Those terminals on the coil are junk. Get the factory style ones with the dual action crimper for connections between each wire and terminal that are gas tight. Gas tight as in oxygen can not get in there and cause corrosion. Corrosion causes voltage drops....

https://www.thesamba.com/vw/forum/viewtopic.php?t=338938

If you will not get the proper crimper, then only solder and heat shrink terminals on.

Ages ago went out to a VW meet and talked to a fellow bus owner who was having intermittent engine cutting out problem. Looked him engine over and saw those junk terminals were on the coil. Reached up and lightly tugged on the power wire, and it fell out with ease. The bus owner was absolutely open mouthed shocked with the result.

If you have to run a fuel filter before the fuel pump, put it under the fuel tank. Fuel pumps do not do well with pulling up thru a filter. Under the fuel tank will at least use gravity to move the fuel thru the filter or if you would rather filter between the pump and carb. Then get the stock metal fuel line back in there.

Get hose clamps on both ends of the fresh air paper tubes going from the fan shroud to the heating system under the rear tin. If one of those paper hoses pops off it can fry a head.

Do post more images of the engine. Then all of us here can point out any more problems.
_________________
In Stereo, Where Available!

[Eric&Barb]

Looks like you are also missing the lower rear cylinder tins. Those are required to fully cool those rear cylinders properly, resulting in warped cylinder and loss of compression. Earlier version in first image of this tin shown below:

Do snap the spark plug cables into the clips that are in the rear of the fan shroud. Spark plug cables do not do well chaffing against sharp edges, or laying over the hot preheat pipes of the intake where the electrical insulation to melt thru and end up all too soon shorting out.
_________________
In Stereo, Where Available!

[Eric&Barb]

Vacuum line between the distributor and carb is suspect. Stock line was metal and had an uphill hump in it to prevent fuel from the carb from making it to the vacuum can and ruining the rubber diaphragm inside. See the LH image in this page from the owners manual of how the metal line should look:

_________________
In Stereo, Where Available!

[Xevin]

Might as well clock the generator properly for better cooling. See Eric and Barb VW manual picture.
_________________
Keep on Busin'

[frenchroast]

Good idea to have the air cleaner on in case it farts fuel vapor out the top with that jumper cable right there.

[70_clementine_vert]

[Eric&Barb]

[70_clementine_vert]

Well, I replaced the ignition switch. That did not fix the problem. The car still will not start until I jumper the positive side of the coil to the battery. Actually to the generator positive post. Picture:

I also took the generator out and rotated it as was suggested above. The bottom two 10mm bolts on the tin attached to the fan shroud were a bugger but I got it done.

I also did put the spark plug wires in the clips. They were there on the fan shroud.

Took some pictures of the regulator and the electronic ignition. I put in my old coil too. I need to fix the rats nest of wires though. Any other thoughts? I am wondering if it has something to do with the wiring to the regulator.

_________________
"In any moment of decision the best thing you can do is the right thing, the next best thing is the wrong thing, and the worst thing you can do is nothing."
Roosevelt, T.R.

[Eric&Barb]

Not a good idea to connect to the generator like that!! Only the regulator should be wired to that!

Either use the license plate light or one of the taillight conections on the LH side of the engine compartment that the sound deadener has been ripped down revealing the wiring connections there.

You need to check for voltage getting to the ignition switch and out of it. Then inspect the positive power wire to the coil at both ends of the wiring harness.
_________________
In Stereo, Where Available!

[VW_Jimbo]

Okay. Enough! I dislike all of this opinion with no factual reference for any of this hypothesized conjecture! Stop!

[VW_Jimbo]

A small percentage of Bugs, back in the day, burned their ignition coil feeder wire. Circuit 15 from the ignition switch. It is a black 14 gauge wire. Once they fry, the voltage carrying capability of the wire diminishes greatly. You may have one of these cars. Any damage noted to the wire harness at the back of the ignition switch, all the way back to under the rear seat at the quarter panel? Like electrical tape wrapped up loom?

Just a thought. Or you could utilize a voltage drop test to prove the integrity of that wire.
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!