How do you know when a clutch cover is worn out?

[tdafforn]

hi guys,
As the header says..
How do you know when a clutch cover is worn out?
I have the clutch out of the car, the friction disc is to worn to put back (<1mm from the rivets), but how do I tell wether the cover needs replaceing as well?
What wears on them?
Tim

[john.p.clegg]

Tim

The only things to "wear" are the spring tension and the friction surface??

John

[Bruce Crowthorne]

I just replaced mine as a precaution.
It cost ?58 from QED (I am sure MUCH less if you look around) so not worth the hassle of taking the engine out if it goes.
Bruce

[1964 S1]

Hi, as John says, the spring tension "wears" but that's it. If you still have the car apart, I recommend replacing what we call the pressure plate, the spring tension can lessen making for a soft pedal and clutch slippage down the road or one can break from heat through the years causing even more slippage. It's worth the price of the part as there is no labor cost involved. Eric

[Frank Howard]

Tim,

And while you're at it, do yourself a favor and replace the release (throwout) bearing for sure and possibly the spigot (pilot) bearing.

[tdafforn]

hi guys,
Thanks for the info..
Have a replacement the spiggot bearing ready to go in and will get a release bearing as the last one disintegrated as I took the engine off.
Tim

[triumphelan]

I would`nt risk it I woud fit all 4 parts metioned and whilst the engine was out the other "usual susspects" aswell

[denicholls2]

One of the things some may forget to consider is that Lotus engines often finish a restoration with considerably more horsepower and torque than they started with. If a Twincam, for example, is going from the stockish 100 HP or so to 125 or even 150, all of that excess meets the driveline through the pressure plate. What was marginal is likely to become bleeding edge, even with a light car to motivate.

In a general rebuild to spec power levels for a car that is regularly driven, I'd expect a pressure plate to outlast two clutches. The disc, after all, was intended to be adequate for a much heavier machine. Wear on the face and metal fatigue in the finger springs due to age are the big factors here, so as is often the case, sitting unused in the garage does not help matters.

[tower of strength]

hi guys,
As the header says..
How do you know when a clutch cover is worn out?
I have the clutch out of the car, the friction disc is to worn to put back (<1mm from the rivets), but how do I tell wether the cover needs replaceing as well?
What wears on them?
Tim

after a shitty weekend and guiness large, the answer is. . . . . . . it slips!!


joking aside, if you've got 1mm depth of friction material to the rivets, then youir driven plate is ok, if you didnt have any problems prior to removal, I'd use the whole lot again, maybe changing the release bearing only. unless of course the cover shows obvious signs of wear,on the drive face and the release bearing surface. also check the driven plate coil springs, if they are loose or broken you will get judder. i have seen clutches in plus 2's shagged after 20K miles and on the other hand perfectly serviceable after 60K!!

Mark

[mikealdren]

As Mark says, the life of a clutch varies enormously - the biggest variable of course is the driver!
Mike

[rgh0]

Tim

When I take my clutch cover to my clutch specialist he does 3 things

He checks the diaphram spring load to ensure it is within spec
He grinds the face of the pressue plate to ensure its flat and has the right surface finish to bed in the new clutch plate correctly
He checks the wear points of the moving diaphram spring looking for cracks or excessive wear.

If the diaphram spring is low in pressure or has excessive wear he replaces the spring, the other components have almost infinite life.

regards
Rohan

[tdafforn]

Hi Rohan,
not sure where I would find such a dedicated mechanic in this country. most of the clutch people aren't interested in the old one, and just want to sell me a new one!
Cheers
Tim

[rgh0]

Tim

You just have to look for them . I am sure they will exist. BGT Brakes in Melbourne are a small old fashioned brake and clutch shop. He races a Lotus Cortina in Historics and is a valuable resource to the historic racing and car club community - it may be worthwhile talking to some of the historic racing guys in the UK and seeing if they know an equivalent

Rohan