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View Full Version : [IRS GEARBOX] Clutch Release Bearing & Guide Sleeve - HELP!



NovaF4
07-05-2011, 06:20 PM
Hello to all VW Beetle gearbox and clutch experts! (hint)

I'll try and keep this as simple as possible. Basically I'm in a bit of a pickle...

I have a VW Beetle IRS gearbox with special COGBOX modified internals, heavy duty side plates etc etc. I have an Alfa Boxer engine. I also have a GB Engineering adaptor plate kit bought 10 years ago and used to good effect with my old swing axle set up (the special input shaft that came with the kit was taken out and put into the IRS one). Since the IRS conversion was done the Nova was never driven and as you know I'm now re-building it.

The GB Engineering kit comprised of:

- Input shaft that goes into the VW gearbox.
- A sliding spacer which fits between the VW clutch release mechanism and the Alfa clutch mechanism.
- An adaptor plate
- A set of bolts

Note: The application retains the Alfa clutch, flywheel and starter motor.

When the Nova was carted off to the garage about 2 months ago I forgot to remove the sliding spacer from the input shaft and on route it slid off and dissapeared into a bush somewhere in Surrey. :cursing:

This is what the sliding spacer looks like:

(THIS IS NOT MY NOVA, IT'S JUST AN EXAMPLE OF THE SLIDING SPACER)
http://www.thegoodwebcompany.com/sfy36k/box_mod.jpg




I now need a new one.

I phoned GB Engineering but they don't make these kits anymore. I did some pleading and they are willing to make me a new spacer "IF" they find the original drawings. But before they start hunting they need to know the answer to this question:

"Does your input shaft have a 'guide sleeve'?".

A guide sleeve looks like this:

http://www.thegoodwebcompany.com/sfy36k/thrust_bearing_guide.jpg

I looked into the Nova's gearbox bellhousing and this is what I see:

http://www.thegoodwebcompany.com/sfy36k/IMG_0923.jpg

As you can see there's not only no guide sleeve but also no Thrust Release Bearing which I definately need.

OK let's start with the clutch release bearing. There seems to be two available but I'm not sure which one I need. Here they are:

http://www.machine7.com/section.php?xSec=358

Help!

Next...

Should my gearbox also have a 'guide sleeve' or not? If so then which one? I have the 3 tapped holes for fixing it to the bellhousing but maybe that doesn't mean anything. Here are the available guide sleeves:

http://www.machine7.com/section.php?xSec=363

Once I've established these things and had the spacer made up then I can fit the engine which was supposed to be this weekend :crash:

Cheers guys

G.

bushboy
07-05-2011, 10:02 PM
Giles,
I have an IRS. below is a pick of mine without the V6 attached. You can see that mine has the slider thing watsit and the thrust bearing attached. I have a new, not needed thrust bearing in the shed. I think it is for the older style bearing forks so may be of absolutely no use to you. I'll attach a pic tomorrow.

No slidyadapter on the V6 install as the kit came with a new fly wheel.

http://i6.photobucket.com/albums/y231/bushboy554/EngineSubFrameMounts001.jpg



http://i6.photobucket.com/albums/y231/bushboy554/kenedyadapterplate.jpg

bushboy

islandman
08-05-2011, 07:55 AM
OK Giles having now seen the photo of your bell housing and spacer it becomes a lot clearer. Your gearbox appears to retain the old forks and original beetle thrust bearing, except that the new spacer collar simply acts as an extension to the thrust bearing to press on the clutch plate. It seems that this design doesnít make use of the original VW collar as the new spacer keeps the thrust bearing vertical. So my guess now is the original collar isnít needed as the CB Engineering spacer serves both purposes.

So bottom line is a new Spacer needs to be machined. Even if they donít have the original drawings all is not lost as you can tell a lot from your photo. The diameter of both ends of the new spacer are the same diameter as a standard thrust bearing. The length can be determined by fitting the forks and thrust bearing first then measuring to the start of the thrust bearing to the beginning of the splines on the input shaft (as per the photo). The middle length is machined down to a narrower diameter simply to shed some weight I guess.

Most machine shops given the photo and some measurements from the gearbox with forks and thrust bearing fitted would be able to do this I think.

Good Luck.

NovaF4
08-05-2011, 10:10 AM
Thanks for your replys. Islandman - Sorry I should have made a note (just done it) that the first photo showing the bellhousing with all the bits on it is not my Nova, it's a photo from the web probably of a VW. It's the second close up photo that is mine. Would you be able to edit your answer based on this?! Sorry :facepalm:
G

NovaF4
08-05-2011, 10:16 AM
Bushboy thanks for the reply and photos. What type of forks does your gearbox have? Are they the same as mine shown in the close up photo of my bellhousing? If so then I presumably should be buying the 'guide sleeve'.

Also I presume that you are using a new type of thrust release bearing as you pointing out that you spare was an old one, right?

All these clues will help me work it out.

p.s. let's stick to the right termanology otherwise it's going to get more confusing than it is already. I'm getting a headache over this!

G

NovaF4
08-05-2011, 10:20 AM
I found this on the web but I think it only confuses me more...

http://www.thegoodwebcompany.com/sfy36k/Clutch_and_bearings.jpg

It's interesting though as the Alfa clutch plate more resembles the bottom drawing.

I'm still no wiser if to have a guide sleeve fitted and what thrust release bearing to have.

G

NovaF4
08-05-2011, 10:34 AM
Just about to go down to the garage but I've had a thought...

Surely this is the way to go about this:

1/ Get official confirmation of what type of forks I have as these I don't want to remove/replace. I've got a feeling that these must be the "Steel Forks" that COGBOX fitted as part of the mod. It's written on the receipt. Anyone in agreement with me there or is there another gearbox part called "Steel Forks"?

2/ Look at the drawings in the previous post and work out which thrust bearing I need. This will also tell me if I need a guide sleeve or not.

3/ Buy the correct thrust bearing. Buy the guide sleeve if needed.

4/ Tell GB Engineering if I have a guide sleeve or not.

5/ GB Engineering comer up with the goods, or I get a fabricators to make one up for me as Islandman suggested.

So, I still need help with identification :dunce:

G

islandman
08-05-2011, 11:18 AM
I found this on the web but I think it only confuses me more...

http://www.thegoodwebcompany.com/sfy36k/Clutch_and_bearings.jpg

It's interesting though as the Alfa clutch plate more resembles the bottom drawing.

I'm still no wiser if to have a guide sleeve fitted and what thrust release bearing to have.

G


Actually this diagram tells you and awful lot. Just take a look at the Alfa clutch, if it is just "fingers" with no ring as per the "71 on most models" second diagram then this is the thrust bearing to go for. If memory serves me this is the one.

p.s. and yes my earlier statements on making a new thrust bearing still stand

ChrisBailey
08-05-2011, 01:49 PM
The clutch system with no sleave is used for the older engines/gearbox, my swing axle uses that type.
The other clutch system uses the sleave and a different thrust bearing aswell as a different fork, its used on the more modern vehicles.
For some weird reason people upgrade the old gearboxes to accept the newer clutch system by drilling three holes into the gearbox.
Your gearbox has the three holes so orginally it is supposed to have the newer clutch system.
As you are using an alfa engine and clutch I would put some plastacine on the clutch plate and bolt up the engine, you can then remove the engine again and you should have the approximate dimension of the sleave you need to make or atleast the distance between the bearing and the plate.
Might be a good idea to put the plastacine into a sandwitch bag so it doesnt stick to your gearbox components.

NovaF4
08-05-2011, 03:48 PM
Actually this diagram tells you and awful lot. Just take a look at the Alfa clutch, if it is just "fingers" with no ring as per the "71 on most models" second diagram then this is the thrust bearing to go for. If memory serves me this is the one.

... I would be inclined to agree with you and ChrisBailey (thanks Chris) but look at the forks on the two drawings. They are pointing towards the clutch in different directions! Is this an error or deliberate? The first says "Bearing sits in this recess", the second one says "Bearing site on this bump". My forks are pointing in the same direction as the first drawing which would suggest the earlier type, contrary to what you and ChrisBailey have suggested. Would you be so kind as to take another look?

Also bear in mind that whatever the answer I still need the 'spacer' that I lost, so although my Alfa clutch plate has just fingers with no ring, maybe the spacer acts as the 'ring' at the clutch end?

Giles.

NovaF4
08-05-2011, 04:07 PM
I've just seen this which is VERY interesting...

http://www.volkszone.com/VZi/showthread ... se+bearing (http://www.volkszone.com/VZi/showthread.php?t=702981&highlight=clutch+release+bearing)

It definately looks like I have the EARLY forks. This would mean that I would need the early clutch release bearing and NO GUIDE SLEEVE.

Anyone disagree?

G

Spacenut
08-05-2011, 06:06 PM
Hi Giles - I agree. If you look at your release forks, the "hooks" face outwards, not inwards. So looking at your drawings, it HAS to be the UPPER one, which has the hooks in the same orientation. Forget about the ring on the VW clutch plate, which you don't use.

So you need the release bearing with the retaining clips, and NO guide sleeve.

The spacer sits over the input shaft (which has been modified so that the splines are Alfa) and bears on the VW release bearing at one end, and the spaced off Alfa clutch plate at the other end. The length needs to be machined accurately otherwise if it is too long there will be a preload on the clutch and it will slip too easily. Hopefully if it is too short the slack can be taken up with the clutch cable adjustment, although it needs to be in approximately the right place.

The sleeve needs to be a good sliding fit on the input shaft - when the clutch pedal is depressed, the input shaft will be stationary and the flywheel, clutch plate and sleeve will be rotating around it.

I seem to recall your old spacer sleeve may have had a phosphor-bronze sleeve internally to allow this movement.

Good luck having the new sleeve made up. Remember - release bearing with no guide sleeve. Pre-71, as you have correctly surmised.

Lauren

ChrisBailey
08-05-2011, 07:03 PM
You can use either clutch system though. The forks are interchangeable, I had to swap my fork from the newer type back to the older type. Yours has the three holes in the gearbox for the sleeve to bolt to. Not sure why you want to put the old type on unless its more convenient? Are you sure your space does not sit inside or around the sleeve?
Sorry if this is confusing things.
But the picture with the space and release bearing has the later type system because you can see it has ears with clips on them.

NovaF4
08-05-2011, 08:31 PM
OK, thanks to all your help I can draw a conclusion, which Lauren has summed up. I have the old forks so will need the old clutch release bearing and no need for a guide sleeve.

Chris thanks for your help but considering the outcome it is more convenient to put on the old type because that saves me having to remove the existing steel forks, purchase the new type forks and then fit them, and then buy and fit a guide sleeve! I don't see the point in doing all that.

Hopefully GB Engineering will find the old plans and get one made for me that is the same as my old one.

Cheers all and thanks Islandman for your time with pre-private messages about this topic.

G

bushboy
08-05-2011, 08:49 PM
Giles,
This is the bearing I have.

http://i6.photobucket.com/albums/y231/bushboy554/photo0163.jpg

http://i6.photobucket.com/albums/y231/bushboy554/photo0162.jpg


I got it from Big Boyz Toyz many moons ago. No use to me so if you want it it is yours.

Bushboy

NovaF4
08-05-2011, 09:24 PM
Hey thanks Bushboy. I've sent you a private message.

MicksRedNova
09-05-2011, 09:48 AM
You can use either clutch system though. The forks are interchangeable,

I agree with Chris. When my clutch failed after MicksRedNova first even run to Detling I went to GSF with the old one and they said the newer 'diaphragm' clutch design is a direct replacement for the older 'three fingers' type, providing you use the correct thrust bearing. This proved to be correct and the new style went right in and works well.

I can't help with the sleeve thing though.

Mick

NovaF4
09-05-2011, 12:40 PM
You can use either clutch system though. The forks are interchangeable,

I agree with Chris. When my clutch failed after MicksRedNova first even run to Detling I went to GSF with the old one and they said the newer 'diaphragm' clutch design is a direct replacement for the older 'three fingers' type, providing you use the correct thrust bearing. This proved to be correct and the new style went right in and works well.

I can't help with the sleeve thing though.

Mick


Hi Mick

So you're saying that your clutch failed and you bought a new different style one (diaphram) and managed to directly replace your old thrust release bearing for a newer style. Is that right? And it fitted on your old forks which are definately the same as mine? Is that right?

That's all good but I'm not replacing the Alfa clutch, which incidentally looks like a load of plates (possibly what you are referring to as fingers), so how does that change things?

It's really all down to the FORKS. Are you saying that your FORKS were not changed and the newer style thrust release bearing fitted? But what about the diagrams that specifically display two forks for two different release bearings?

Also what's the advantage of using the newer style thurst release bearing over the older style?

Regarding the guide sleeve, from what I have learned this would be necessary with the new style release bearing.

G

ChrisBailey
09-05-2011, 01:40 PM
the advantage I see in using the newer type is that its designed to fit a clutch plate without that metal ring, this would suit your alfa setup.
The old style uses a ring on the clutch plate probably to reduce the amount of wear on the thrust bearing from the sharp teeth of the clutch plate.
Personally I think you could use either, but they do have different spacing for the two different plates.

NovaF4
09-05-2011, 03:53 PM
Hi Chris. I'm getting conflicting reports about the forks - You are saying that the forks are interchangeable. Are you sure? The Machine 7 website and the drawings suggest otherwise.

The "spacing" wouldn't be an issue as GB Enginnering, who will be making me the spacer, have asked if there is a guide sleeve or not, presumably as they have two sizes of spacer to choose from.

Can you elaborate on why it would be an advantage using the newer type relese bearing? You are right that it is designed to fit a clutch plate without that metal ring, and yes my Alfa clutch indeed doesn't have the metal ring, BUT there will be a spacer in between with two round bearing surfaces on them at each end. Surely that make this advantage irrelevant?

Cheers,
G

ChrisBailey
09-05-2011, 06:43 PM
Yes I suppose using a spacer would make that part irrelivant.
Im just letting people know that you can use either fork, I have had both types on my swing axle gearbox.
The older thrust bearing has the problem of falling off the forks, those clips have a habbit of coming off, thats why the later type is integral.
But if I was in your shoes I would use the older style clutch simply because you have half of it already.

NovaF4
09-05-2011, 07:00 PM
I'll use the old one. Hopefully bushboy's that he's offered me. I've noticed that his older style release bearing comes with heavy duty clips (as does an offering from Machine 7), which must be available due to stories of the other ones coming off.

Thanks all who have contributed to this issue and sorry it has been so boring. Maybe it will help others one day.

Giles.

MicksRedNova
10-05-2011, 01:51 PM
Giles

Not sure if its any help but I happen to have pictures of the old and new clutch bits so I'll post them here:

Old type clutch fitted:
http://i133.photobucket.com/albums/q49/MickAtHome/old_style_clutch.jpg

Old type release bearing:
http://i133.photobucket.com/albums/q49/MickAtHome/old_thrust_bearing.jpg

Where the pin clip things go (mine had dropped off and was lying in the bellhousing)
http://i133.photobucket.com/albums/q49/MickAtHome/pin_clip.jpg

New style clutch fitted:
http://i133.photobucket.com/albums/q49/MickAtHome/new_engine.jpg


I don't have a pic of the new release bearing fitted, but it went on the old forks in the same way.

Mick

NovaF4
10-05-2011, 02:09 PM
Thanks a lot for the photos Mike.

I am now pronouncing this thread well and truly OVER!

:outahere:

Peter
11-05-2011, 07:04 AM
Unless you wana discuse using a hydraulic thrust bearing he he

NovaF4
11-05-2011, 11:35 AM
NO!! :scared: :cry: