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I have a 1963 3.8 Mk2 with the early MOD Moss box and now requiring a new clutch.
I have seen some 3.8 Mk2s advertised for sale stating they had the lighter E Type clutch fitted . Is it a case of one having the option to use the early spring type plate and cover or go for the more modern diaphragm unit.
Shall i have to get a matching e type 3.8 flywheel or does one just have their origional flywheel drilled and threaded to suit new stud location ? Prior to fitting is it essential to have the clutch all balanced especially if flywheel had to be drilled / tapped. Is there any need to change the thrust / release bearing and fork ? I remember reading somewhere a knuckle on the inner wall of the bellhousing has to be grinded down when using a different cover. Not sure if it was relating to the diaphragm one i am thinking of using though but I do believe it was relating to the Moss box in Jags.
At the moment i have an opportunity to locally buy a new old stock 9.5" 3.8 early E. Type diaphragm clutch cover . If patient they might find matching plate for me if i buy the cover as it would have been from a 3 in 1 kit . They do not have any early spring type clutch covers. Will either type clutch plate work with this later type cover given little difference in dimensions ie, 9 1/2 and 9 7/8" , i am not sure of inner plate to engaged diaphragm clearance though.
I am in no rush to have the clutch changed but AM KEEN to make a marked saving in cost if the later type can be fitted.
Any words of experience in such matters will be greatly received.
Thanks 600 FGJ. Eugene.

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Not related and I don't know anything about the various clutch diaphragms but my clutch was ridiculously heavy ('65 3.8S).

I've had many older cars, vans and SII Land Rovers but this was a bit much even by those standards.

Simply replacing the flexible hose made a huge difference. It's actually pleasant now.

Simon

Thanks for that Simon.
I had intended changing All clutch and brake hoses but interesting to know the flexi hose alone can make such a difference.
As i said the lighter to use e type is desirable let alone the savings i can make in buying one.
600 FGJ
Eugene.

Eugene, if you haven't tackled this already theres a few things to bear in mind.

Whichever type you use (diaphragm or spring) you can't interchange parts from the 'other' clutch kit. The centreplate of a spring clutch is 10" diameter, diaphragm type is 9.5". The clutch covers are different heights too, meaning that the release bearing has a different offset for each clutch.
Strictly speaking, a diaphragm clutch should use the longer (self-adjusting) slave cylinder, but in practice you should be able to continue using the shorter one with the manual setting. The release arm in the gearbox doesn't need changing.
You may find your flywheel is late enough to be drilled for both types of clutch - I'm not sure when production changed, but earlier cars than yours (1960-61) would only have holes for the spring type. The holes in the flywheel for a diaphragm clutch will be 5/16UNF, instead of the 3/8UNF fixings that hold the spring type. Locating dowels are also different.

When you split the engine & 'box, look inside the bellhousing. If theres an 'outcrop' of aluminium immediately above where the clutch slave cylinder mounts, you MUST file or grind this off, or it will foul the new clutch cover. Rotate the engine by hand when the 'box is refitted, to double-check there are no clearance issues.

Balancing a clutch cover alone is relatively pointless but in the event of a full bottom-end engine rebuild, having the whole crankshaft assembly done - along with the pistons & rods - is definitely worthwhile.

Hope that helps.

Hi Pete, sorry for delay in thanking you for your valued response.
Due to health issues no movement has been made on major tasks such as clutch.
Regards
Eugene.

Hi Eugene

Pete is sort of right except that you can use a 9.5 inch clutch plate with a 10" clutch cover. This is the set up I have on my E-Type to which I have fitted a T5 gearbox.

The good news is that it is not necessary to re-drill the flywheel for this set up.

Obviously, a 10" plate won't fit with a 9.5" cover.

Hope this helps.

Regards
Stuart

Stuart, I may be missing something here, but where is the advantage in using a 10" spring clutch cover with a 9.5" centre plate?? There isn't really any weight saved by doing so, and the friction material on the centre plate is liable to overlap the i.d. of the cover by 2 or 3mm, which won't help its longevity.

Hi Pete

I get your point. My point was that you don't need to re-drill the flywheel to use the smaller clutch plate.

I don't recall any overlap of the lining materials on the I/D but remember I used a T5 gearbox kit from Derek Watson so the clutch plate may be a different one to that used in the standard E-Type 9.5" unit (input shaft splines may be different).

I guess it is expedient to do this, rather than risk the engine going out of balance due to replacing the clutch cover plate.

Stuart