Big gap between release bearing & clutch cover?

[primer]

Hello folks, I've been reading around on here on and off for a year or so as I've been building up a P5B 3.5l RV8 for my Capri but havnt really posted anything.

I have a question now though, so thought it best time I stuck my head up!

When I bolt my gearbox upto the block I find a big gap between the release bearing and the clutch cover.

Its a P5B 3.5 motor (early CR version but machined for lip seals), SD1 flywheel, AP super heavy duty clutch plate & cover (brown?), SD1 bellhouinsg & g'box. The gearbox has a G16A code on it, which I believe means its from a 2000cc varient.

Its got me stumped. I've had a few problems with the build so far, but nothing I couldnt work out with a bit of reading and fiddling. AFAIK all the parts are 'correct', but nonetheless, the relase fork is almost flat against the back of the bellhouisng before it comes anywhere near the clutch cover? I wondered if I had some strange short pivot but with the release bearing sitting right back to the 'box on the input shaft, theres still the big gap!

Im pretty much pulling my hair out at this point. If anyone can shed any light on it I'd be over the moon!

[gelmonkey]

Hi Primer
Its very possible that you have the wrong bearing carrier installed.
The non V8 carrier is much shorter than the V8 version.
If you could measure the carrier from top to bottom and let me know I can measure the spare V8 one I have here.
This might not be the problem area but it is a good place to start.
cheers
Paul

[primer]

Hi Paul, thanks for the reply. I've been busy with the tape measure this morning. I didnt know how much would be relavent so I tried to measure everything. ....and took pics!

The nose of the input shaft is about 10mm short ther the depth of the bellhousing, and sits nicely in the spigot so Im pretty sure the bellhousing, crank tail & input shaft are all correct. I wondered if the CRB wasnt the problem, wether or not it could be to do with the depth of the flywheel setup not being deep enough to 'reach' the CRB? Measurements are as follows;


CRB (inc. bearing) - 68mm
Flywheel friction face beyond block - 21mm
Spigot end (flush with crank tail) to spring fingers - 53mm +~
Bellhousing depth - 180mm +~
Flywheel friction face to spring fingers - 45mm +~
G'box Input shaft (beyond bit CRB sits on) - 100mm
Pivot Ball - 43mm +~

[gelmonkey]

Hi Primer
Sorry for the delay in coming back to you.
I have measured my carrier and have a 70mm inc bearing.
The pic you have sent is without the bearing or is the bearing the little silver bit right at the end?
The bearing on mine is quite big.
From the pics your flywheel looks quite thin and I dont have a spare one that I can measure for you here.
It is possible, as you have already mentioned, that the flywheel is incorrect and would suggest that you ask on the forum if someone can measure a standard 'wheel for you.
Everything in your pics looks ok other than the flywheel but I may be wrong about this.
cheers
P

[primer]

Hi Paul,

The flywheel in question is the one mentioned in the topic I posted a few months ago (the only other one). I took it to a machine shop and had it checked for warping, stress cracks etc. and we took a few thou off the face (just enough to get through the hot spots). We did however find that the filings it threw were black and dusty, indicating that it was cast and that (I would imagaine) an OEM item. It'd certainly be handy to be able to compare it to a known 'correct' flywheel but i cant imagine it making up for the inch or so of gap!

The CRB pictured (and measured) includes the bearing. It looks as if its moulded in? -This is why Im a bit hasten to buy a new one. Thier pretty pricey and im 90% sure its the right one already.

I'll put a post up about the flywheel thickness. Fingers crossed!

-Tom.

[gelmonkey]

Hi Tom
The other thing that you could ask about is the actual pushrod from the slave cylinder to the thrust release arm.
There might be different length items for the 2.6 and the 3.5.
From memory and it is old and muddled these days, I remember that the pushrod on my set up is proud out of the front of the bellhousing.
It does seem that you have an OEM wheel so there should,nt be any problems with it.
I'm not sure but I think the release arms are the same length on 2.6 and V8.
Someone will surely put me right on this.
Hope this helps
Cheers
P

[primer]

Hi Paul,
I originally took the pushrod from the same place my master & slave cylinders, flexi hose & fittings came from; a late 70s range rover. The pushrod was indeed the wrong length so I bought a brand new V8 one, along with retaining clip. With the CRB sat in its 'resting' position and the arm sat on its pivot, the pushrod sits nicely outside the bellhousing.

Im going to have a really good go with the tape measure and draw up a diagram tonight or tomorrow and try and get my head round it. I've come this far with it, Im not gonna be beaten now!
-Tom.

[SuperV8]

I have the CRB (plastic type), pivot and push rod sitting in my garrage after my re-build. I will measure them when i'm next at my garrage. Should be tommorow evening.

Your flywheel looks similar to mine from memory. I can't measure that as it's in my car.

Tom.

[Coops]

have found different length pivot pins for the release arm also.

[topcatcustom]

I had this conversation with Jim Robinson a while ago when I did the clutch set up on mine, there are about 3 different pivot post sizes, and the same number of CRB carriers (IIRC) - basically when its all bolted up you need to have about 1/2" of the push rod protruding from the bell housing when you hold it in place.

PM JRV8 on here, I got all my parts from him and extremely helpful guy.

[russell_ram]

I'm certain you have the wrong slave cylinder. The depth of the recess that receives the operating rod on an SD1 one is much less than that on a RR/Discovery one - check the part numbers, are different. The rod length may also be different, but my memory is lapsing on that bit.

As already stated, there are a few different pivot ball heights aswell but if your box came as per the picture then it's probably correct , and it looks about right as do the rest of the parts in your pictures.

I have a new cylinder at hoome that I can measure later if it would help.


Russ

[primer]

Thanks for the continued interest folks, its really appreciated!

Hmm, different length pivot pins and pushrods would alter the amount of pushrod protruding from the bellhousing, but surely it wouldnt affect the position of the CRB when its at rest?

Im going to have another look at it when I get in from work and draw up a diagram to try and explain it a bit better.

Russ; According the the RPi 'Partsrange' eBay shop, the slave cylinder is identical on just about every RV8, the only difference being in the union threads. This, and the fact is was far easier to source is why I went for the RR setup.

[topcatcustom]

I was told that the slaves were the same, obviously I can't guarentee it though as not had mine operating yet!

[DEVONMAN]

Thanks for the continued interest folks, its really appreciated!

Hmm, different length pivot pins and pushrods would alter the amount of pushrod protruding from the bellhousing, but surely it wouldnt affect the position of the CRB when its at rest?

Im going to have another look at it when I get in from work and draw up a diagram to try and explain it a bit better.

Russ; According the the RPi 'Partsrange' eBay shop, the slave cylinder is identical on just about every RV8, the only difference being in the union threads. This, and the fact is was far easier to source is why I went for the RR setup.

Hi Primer, Just going back to square one on this for a moment, when you say there is a 1/2" gap between the CRB and clutch fingers when the CBR is at rest, do you mean when the CBR is hard back at the gearbox. If so, then this seems normal to me. There is normally an initial gap with a new clutch and as the clutch wears this gap will get smaller as the fingers move back towards the CBR.
So to clarify, are you saying that with the CBR touching the fingers, you cannot get any further pivot action of the release arm.
Regards Denis

[primer]

Hi Denis,
Yep, thats basically it. I think theres a little more than 1/2" gap but I'd like to re-check more precisely.

Your right in saying that Im running out of throw on the fork before the CRB comes into contact with the fingers. -My concern is that not only will I not be able to disengage the clutch, but also if the CRB dosnt sit back against the 'box (or pretty close), then the slack in front of it may allow the fork to find its way off the pivot ball, or the pushrod to come out of the slave cylinder.

If I get chance this evening I'll take some more precise measurements and post them up.