1960 Roadster slipping clutch, engine rebuilt 800 miles and 23 years ago

[Vincent Chiaro]

So this is kind of a weird one, but I have this 1960 Roadster. The engine was rebuilt in 1998 by the previous owner, driven about 300 miles and then parked for 23 years. Records indicate that the clutch was replaced at that time.

The previous owner diligently started and ran the car in his warehouse nearly every month for the next 23 years. But he never drove it, so he would have never used the clutch in a normal manner.

Since acquiring the car this past February (Bill Eason at Eason Autowerks went through it to get it road worthy again), I've been driving it and have put about 800 miles on it or so. Bill's advice was to treat them like break-in miles since the car didn't have many miles since the engine rebuild.

The car runs great (Leo Droughton did the engine rebuild back in 1998) but now I've noticed the clutch is slipping. I'm generally pretty easy on clutches and have been driving stick shift cars for 27 years. Is it possible that from sitting / lack of use / only being used in neutral the clutch would need to be replaced?

Knowing how a clutch works, the disc would have been engaged with the flywheel even at idle in neutral but if that was the only way it was used for 23 years would it cause a problem?

[Martin Benade]

Sitting should have no effect on it. Does it still have normal free play? If so, it was probably never quite right. Maybe the flywheel was machined too deep.

[Doug McDonnell]

Or maybe it was never adjusted properly after the rebuild. If you are comfortable going through the adjustment procedure do so. If not have Bill take a look at it. Certainly possible that a seal could be leaking also after sitting that long. I doubt that it is a problem that can't be fixed easily. Congrats on your find. My late friend had a 60 Roadster and they are great fun. https://www.youtube.com/watch?v=jLHWAsU ... ex=7&t=26s

[Bill Sargent]

The first thing that comes to my mind would be a rear main seal that has deteriorated and is wetting the clutch disc with oil, causing it to slip. If that is happening I would expect to see a little puddle of oil on the floor where the engine and transmission mate. If there is no oil, then I would suspect that either the clutch was not adjusted properly when the motor was reinstalled or that there is a problem with the clutch components. Regardless, it should be relatively easy to solve, but it may require pulling the motor to check the clutch.

[Martin Benade]

Is oil able to get into the clutch from the main seal? I’d think it wouldn’t.

[Vincent Chiaro]

Checking the clutch adjustment shows it just around 1" of free play (maybe a little bit more) with the engine/transmission cold. I think the manual says it should be checked while warm so I'll go for a spin tomorrow and re-check. (Does it matter if I check it while the engine is running or off?)

The car is very dry underneath, so hopefully no oil leak.

[Martin Benade]

Better pull the engine and investigate.

[Vic Skirmants]

Is oil able to get into the clutch from the main seal? I’d think it wouldn’t.

Definitely can.

[Martin Benade]

I’ve had good luck then.

[Larry Brooks]

Does the car have a really light clutch pedal? About 25 years ago I bought an F&S "356" clutch for a great price from a vendor who is no longer in business. I noticed right away that it took very little effort to push the pedal in. The clutch worked OK at first, but started slipping badly after a few hundred miles. I pulled it out and luckily hadn't cooked the flywheel yet. I bought a new clutch assembly from a local vendor and noted that the disc was thinner on the previous one. Also when we tested the spring pressure on the pressure plates there was a very noticeable difference. We guessed that the vendor had sold me a VW clutch assembly, but never confirmed this.

[Vincent Chiaro]

Larry - I've only driven this 356 so I don't have a good baseline for comparison but no I definitely wouldn't call it a light clutch pedal feel.

[Jacques Lefriant]

hi
maybe the spring broke if it were a diaphram one.
j

[Dick Weiss]

I don't think a flywheel seal leakage would effect clutch slippage since it's behind the flywheel's face.
More likely from the transmission's main shaft's seal; Trans oil is thicker and it smells different than engine oil.

The other possibility is the flywheel's depth for the 180mm disc was cut but w/o the relationship of the face cut
for the P/plate; Further, a new VW disc is thinner (near the Porsche's wear limit) vs near 10mm thickness.
The correct depth is listed in the shop manual and spec book.

[Harlan Halsey]

1. Adjust the clutch to 1" free play (Adjust the pedal stop too)
2. If it still slips, pull the engine, assess the situation, repair.
Shortcut: Grab the clutch lever on the transmission. If there is free play, go to step 2.