Thickness of new clutch?

[sewebster]

I have a 1991 with the 5 speed. My clutch is off because I'm rebuilding the engine, so now would be a good time to replace it if necessary. The factory manual says to replace if it down to less than 0.3 mm above the rivets. I have two depths of rivets on mine, but it is about 1.25 mm above the taller rivets (more to the lower set). Anyway, 0.3 mm sounds like not very much... I'm wondering if anyone knows what the clearance is when new so I can tell how used up my clutch is... ?

 

Thanks!

[jj big shoe]

I'm not sure but unless you're flat broke its a good idea to replace everything clutch related while its apart. An Exidy clutch kit (clutch disk, pressure plate, release bearing, plot bushing and alignment tool) will run you around $130 or so. The clutch disk alone will be between $50 and $70 if you can find one outside a kit.

[sewebster]

Well, maybe not quite flat broke yet, but I'm getting there with the cost of this engine rebuild. I hear what you're saying, but if all the parts are already almost brand new then there is really not much point. Hmm. I agree that the kit seems to the be way to go if I do anything.

[jj big shoe]

My release bearing started howling and I was looking at that same 0.3m measurement when I had the clutch out. It was well within that spec but I decided to get the kit anyway. My old one maybe had 3000 miles on it and IIRC it looked a good bit thinner than the new one.

[Precise1]

.3mm is .012" of an inch, and not much at all. I would never install a clutch that was close to this as by the time you know you hit the rivets, you'll need to reface the fly wheel. Also, I'm willing to bet that different manufacturers have different thickness/clearance friction pads.

I do not recall what the rivet clearance is on a new clutch but 1.25mm (.05") must be somewhat worn. I'd replace it unless you like pulling trannys.

 

Either that or go to a local auto parts store/dealership and look at one of their cluches...

 

B

[sewebster]

Yeah, maybe I should just do it. I should have mentioned that the reason I don't know how long it's been in there is that I just bought the truck.

 

Any ideas why the inside of the bell housing is full of black goo? I guess either the rear main seal of the engine was leaking or there is a leak in the front transmission seal. I guess I should check the FSM to see how easy it is to replace that (got a new rear crank seal already of course).

[XSrcing]

A little bit of oil, some condensation and clutch dust create that black goo. Go ahead and replace the rear main seal.

[sewebster]

A little bit of oil, some condensation and clutch dust create that black goo. Go ahead and replace the rear main seal.

 

Yeah, already done I guess I'm just wondering if my transmission seal could be leaking too. Probably it's just from years of build up. I guess I'll clean it out and keep an eye on it when I next reopen things.

 

Ordered a clutch kit, might as well stop thinking about it.

Edited October 5, 2010 by sewebster

[Precise1]

A little bit of oil, some condensation and clutch dust create that black goo. Go ahead and replace the rear main seal.

x2

 

If you have a leak, you'll see it. I just cleaned my bell housing out, replaced everything and reassembled. Make sure your kit has the throw out bearing.

 

B

[sewebster]

The new clutch is about 1.55 mm above the rivets, so I guess my old one wasn't really very used up. Oh well. I think I needed a new release bearing anyway. I'd still not really recommend reinstalling one that only had 0.3 mm left though.