Since Click and Clack are Retiring

[Bok_Tukalo]

I have a noodler.

The car in question is a stock 1967 Alpine Series V.

The problem is, when the clutch is engaged, the car will both not start and will die if idling. In neutral, the car starts easily and idles fine. I can drive through the gears easily (since the clutch is engaged for too small an interval of time).

Any suggestions on the root (I resisted the "Rootes" pun) cause?

Thank you.

 

[RootesRacer]

Your crank thrust bearings are worn/have fallen out or the clutch TO bearing has worn all its graphite out.

 

[Bok_Tukalo]

Your crank thrust bearings are worn/have fallen out or the clutch TO bearing has worn all its graphite out.

Thank you, sir.

If it were the throw out bearing, would there be a whine associated with its failure?

I ask because there isn't any noise when the clutch is engaged.

 

[RootesRacer]

Thank you, sir.

If it were the throw out bearing, would there be a whine associated with its failure?

I ask because there isn't any noise when the clutch is engaged.

Not always, the bearing gets down to the end of the graphite and the clutch thrust runs metal to metal but there is still enough graphite to keep from squeaking.

 

[Nickodell]

I'm confused. By "clutch engaged" do you mean with the clutch pedal depressed? I've always understood that the clutch is actually engaged when the pedal is released.

I'm not trying to be a PITA, but it sounds like your problems are with the pedal depressed, i.e. clutch disengaged.

 

[Bok_Tukalo]

I'm confused. By "clutch engaged" do you mean with the clutch pedal depressed? I've always understood that the clutch is actually engaged when the pedal is released.

I'm not trying to be a PITA, but it sounds like your problems are with the pedal depressed, i.e. clutch disengaged.

Thank you.

You are correct. It occurs when the pedal is depressed. The car only idles normally when it is both in neutral and the pedal is released.

 

[snamelc]

A drop in engine RPM is normal when depressing the clutch pedal because I believe these clutches are centrifugal assist, meaning that they do take a little engine power to keep them released. If your RPMs at idle are already a bit on the low side and your tuning is just a little out of whack, idle speed can be pushed low enough that the engine will no longer run. Of course, this could be helped along with a bad throwout bearing. It would be easy to check all this out by bumping up your idle speed a couple hundred RPMs to see if it still dies when you depress the clutch pedal. I couldn't find any reference to this in the WSM but I have always noticed a little drop in RPM when depressing the clutch pedal, even with a new clutch and throwout bearing.

Hope this helps.

Bill

 

[puff4]

Sounds like thrust washers to me. It's easy to check... with the engine off, simply depress the clutch, then go to the front of the motor and use a suitably long lever to prise the crank pulley back into the motor. If the movement is perceptible (i.e. more than .002-.008"), you may have some pretty worn thrust washers. If you're not sure of the exact movement, install a dial indicator on the pulley and check it more accurately by repeating the above test. If the thrust washers get severely worn they can drop out entirely allowing the crank to move fore and aft as much as 1/4", meaning you won't get full clutch disengagement and the engine may well stall when the clutch is depressed (i.e. your symptom). If the washers have dropped, do *not* start the engine again - it needs immediate replacement of those washers (and very likely a rebuild while your at it). Running the engine with dropped thrust washers will destroy the crank and block in *very* short order.

A broken throw-out bearing (i.e. the carbon is degraded below the housing or has disintegrated) will make significant noise when the clutch is depressed and you'll also feel it through the pedal. I would guess that this is not the case here.

 

[Ken Ellis]

Since I'll be checking mine as well, for similar, but milder symptoms... Where do you recommend as the pivot point for the prybar? If it's on the chassis, would the crank move before the elastic engine mounts give? Or should I go the dial indicator route, with the indicator mounted on the engine?

Mine drops in rpm, but only stalls if I've got idle set down to 600-ish. At 8 or 9, it's fine... Throwout has 2000 miles or less on it, and no clutch-riding.

 

[puff4]

It won't take much effort - remember, the crank is sliding in lubed bearings - so the motor mounts won't really move much, if at all. Pry from anywhere you can get purchase - it kind of depends on the pry par (whether it has a bent end or not, length, etc.). A light shove should do it. Using a dial-indicator to measure the movement is the best way to ensure you're spot-on, of course. Mount the dial indicator on then engine if you can (unlikely) but you could just as well mount it on the frame - as I say, the mounts won't move much, and even if they do they'll spring back so your measurement will be the same.

 

[sunbby]

I seem to remember I used a long screwdriver against the cross member to lever the pulley back and check for movement.

 

[Dzynr_Ron]

OK heres a tangent, you're losing ground when depressing pedal ?
I had a cortina once that was grounding only thru the handbrake cable, when tight it grounded, when slack it wasn't, a proper ground fixed it...
I can't see a clutch just shutting off engine, might labour or such but not just not run.?
Ron