Strange VW bug trans/clutch problem

widebody911 · widebody911's Garage

A local kid has a 1966 VW bug with a 1600, and has developed a vexing mechanical problem. He was driving to work one day, and when he got off the freeway, he could no longer get the car into gear. The symptoms are similar to those of a broken clutch cable - he can't get the car into gear with the motor running. He has to shut the car off, put it in gear, start it in gear, and then synchro-shift it. When he needs to stop he has to shut off the car.

He's since replaced the friction disk, pressure plate, and clutch cable, but not yet replaced the throwout bearing. The transmission case boss for the clutch arm had cracked and lost a small piece, and he and a buddy of his milled a nice replacement sleeve for it - the arm is in there solid. We checked the clutch cable tube and that seems to be intact. They did a test where they activated the clutch arm directly with a ratchet strap (taking the cable out of the equation) and were still unable to get the clutch to release.

After he put the new clutch in, he drove it a couple of mine and he said it seemed "ok" but didn't seem to have the same clutch "bite" as before. After a couple of miles the problem came back and he had to synchro-shift it to get home.

I'm stumped. The local VW shop is stumped. Do any of you guys have ideas?

Alan A · 01-09-2018, 06:43 PM

First guess would have been the TOB.
Especially if it hasn’t been replaced.

Are they shimmed to height in a bug?
Make sure that’s right too.

john70t · 01-09-2018, 06:49 PM

Quote:

Originally Posted by widebody911

The transmission case boss for the clutch arm had cracked and lost a small piece, and he and a buddy of his milled a nice replacement sleeve for it - the arm is in there solid.

Could the pivot ball seat or the cable pull angle be walking around whenever the case flexes?
Or just adjusted too low so not enough throw?
Arm installed upside down?
Clutch cover has loosened up?
Pilot bearing very wobbly and causing misalignment?

A cable too tight would engage it all the time(the opposite). Too loose and no shift. But the strap test removed the cable from the equation.
Random is difficult to diagnose.

wdfifteen · wdfifteen's Garage

Pilot bushing dry and/or disintegrating and grabbing the input shaft.
Rear main bearing thrust face so worn the crank is moving. Any oil leaks in the bell housing ?

Mark Henry · 04:31 AM

Bowden tube is shot and/or the in the tunnel steel tube the weld has let go.
Bowden tube needs a 1.5 inch +/- curve in it, they fall apart, fail at the two ends or develop a sharp corner when the interior spring fails.

The weld in the tunnel fails, it's just behind the passenger seat, you must hole saw a large access hole in the tunnel, right side and reweld the tube to the pan. Care must be taken not to burn through the clutch tube when welding.

There could be other factors, but what you're describing sounds like these issues.
Look on thesamba forums for how to's.

Quote:

Originally Posted by john70t

Could the pivot ball seat or the cable pull angle be walking around whenever the case flexes?
Or just adjusted too low so not enough throw?
Arm installed upside down?
Clutch cover has loosened up?
Pilot bearing very wobbly and causing misalignment?

A cable too tight would engage it all the time(the opposite). Too loose and no shift. But the strap test removed the cable from the equation.
Random is difficult to diagnose.

It's not the same as a 901/914/911 trans release bearing arm.

Quote:

Originally Posted by wdfifteen

Pilot bushing dry and/or disintegrating and grabbing the input shaft.
Rear main bearing thrust face so worn the crank is moving. Any oil leaks in the bell housing ?

I don't think this would be the issue but I would check these items.

Quote:

Originally Posted by widebody911

. The transmission case boss for the clutch arm had cracked and lost a small piece, and he and a buddy of his milled a nice replacement sleeve for it - the arm is in there solid.

I'm stumped. The local VW shop is stumped. Do any of you guys have ideas?

You can get a kit that replaces the arm and bushings.

Geary · 01-10-2018, 11:38 AM

As stated, the pilot bearing located in the gland nut has likely seized on the input shaft from lack of grease.

GH85Carrera · GH85Carrera's Garage

Doing a clutch job on an old bug is pretty simple. Dropping the engine is a super easy job.

One of my buddies had a 914 that the weld on the bowden cable gave up. We had to have a tig welder weld it up.

widebody911 · widebody911's Garage

Looks like the pilot bearing grenaded

porsche930dude · porsche930dude's Garage

ouch thats why i always use a bushing instead of a bearing. My brother had major problems with the coil spring style pressure plate in his bug. He couldnt get it adjusted right. Replaced it with a finger type and it fixed it.

wdfifteen · wdfifteen's Garage

Bronze bushings worked for years in those cars. It was crazy to put a roller bearing in there.

john walker's workshop · 01-10-2018, 07:55 PM

Did the main shaft survive? Just fixed a shortened G50 that that happened to and the shaft was toast.

Geary · 01-11-2018, 04:56 AM

Porsche OE mainshafts must be perfectly straight to run true, while VW's ingenious 2-piece mainshaft is VERY easy on pilot bearings. However, the needles require a bit of clean grease now & then. This is obviously a case of a very neglected pilot bearing.

widebody911 · widebody911's Garage

I asked him if he'd put a glob of grease on the pilot bearing when he installed the new engine and I got a the what?.

GH85Carrera · GH85Carrera's Garage

Quote:

Originally Posted by widebody911

I asked him if he'd put a glob of grease on the pilot bearing when he installed the new engine and I got a the what?.

Ouch.

One of my friends has an appropriate saying for that type of error.

There is just no f**king like a self f**king. It will be a lesson he never forgets. And it is the difference between knowledge and wisdom.