missmatched clutch arm ?

[phoenix]

I measured the height of the actual carbon at 7mm on both the new one and the one supplied with the car.

[mgcjag]

Post a photo of your release bearing....is it like the tall one on the right of the photo I posted way back...if not then you have the wrong one....Steve

[phoenix]

I measure the height of the carbon on both the one supplied with the car and the new Girling one and they were both 7mm. Today I mated the box on the engine took the slave cylinder spring off and again the arm would travel all the way to the end of the opening .

[mgcjag]

I Don't think your following the release bearing issue...forget the carbon..yes they all have about the same thickness carbon....what makes them different sizes is the depth from where the carbon starts to the center pivot point....look here both Jag...you need the deeper one on the right.....is this what you have

[caveman]

[rfs1957]

FWIIW there are two versions of the operating arm, one is cast and the other - presumably earlier - is forged.

They both have the same part number cast/forged into them.

I mention this simply because if the shape doesn’t suit the application, because of mis-matched components and/or different bell-housings whatever, the forged ones can be easily and safely (in my experience, limited to 1 car) be heated up and bent.

The cast ones obviously just fall apart.

If you search rfs1957 / “New clutch and thrust bearing” you ought to find the posts recounting why I had to discover this, it’s not convenient for me to dig this link out right now, sorry.

It also has a drawing of a standardised convention as to how we should measure the “height” of thrust bearings so that we don’t go around in circles with people who don’t understand the indulgent help Steve is trying to provide.

[phoenix]

Can anyone tell me the outside depth of the bellhousing the one I have is 7 1/2 inch. This is the only thing i can think of. Engine block to gearbox.

[mgcjag]

Have a read right through this thread viewtopic.php?f=3&t=16018&hilit=Clutch+fork

[phoenix]

Hi thanks for your trouble guys but I have just found out the answer after a week contacting people in UK. the bellhousing that I was supplied for this full nuts and bolts build is the wrong one. it all fits ok But it is about 10mm longer. This fault has caused me to complete the car and then have to remove engine and box and you know the problem that is. This is virtually a new build . New floors all beyond bulkhead new full respray etc. I would love to get hold of the chap that supplied the bellhousing. Researching there are differences in the early 4.2 Jag bellhousings throughout the 4.2s E type and saloons .

[mgcjag]

Please give us more info on the bell houseing...what did you have and what are you useing now....iv seen a lot of differend bellhouseings/clutch set up used on replica C type builds(4.2 jag) ...every one was able to be sorted with the correct clutch and specifically the correct release bearing......do you actually have 2 4.2 bell houseings of different lengths..can you post photos...thanks...Steve

[phoenix]

Thanks for your help (again) guys. I have found the answer. Its the wrong bellhousing, it is about 10mm to big. It is probably from a saloon variant. I was given this project car as a almost complete set of parts not really knowing parentage of all the parts and the owner did not take it apart . When building cars I must admit I have never checked the clutch arm travel before but I will in future as you know the work involved getting the engine and gearbox out. Bryan

[phoenix]

Solved it. It is the wrong bellhousing it being 9mm longer probably from an XJ6.
Thanks for your help anyway guys . Bryan