Flywheel and clutch help please

[molten]

Received new clutch cover today so on with fitting the clutch.

Put DTI on flywheel (3" from centre) to check driven plate surface run-out. Spec says not to exceed 0.51mm. Actual was 0.3mm so ok there.
Concetricity spec : not to exceed 0.100mm. Actual was 1.5mm!!. How do i get this sorted? Will it cause me a major problem?


Also, I decided to fit the clutch and have a couple of concerns.
The drive plate is not a triumph but is a 10 spline x 7 1/4" (i am using d-type box) used on morris minor 1000 amongst others. The central boss is slightly more proud than the triumph at flywheel side and cover plate side.

I torqued up the cover bolts to required spec and noticed that the tips of the pressure plates is about 1mm off the driven plate. Is this normal?

Thanks

[junkuser]

Looks like the wrong plate for that cover or the wrong way around (if that is possible).   Not enough distance between the fingers and the hub.  

[Nick Jones]

The diaphragm fingers have to move inwards to work so the 1mm to the spline hub is definitely a problem!  Friction plate in backwards?

If it's not I reckon it's the wrong one and too thick.  Are the pressure plate and friction plate supposed to be part of a set?

Not sure I'm understanding you on the concentricity question........  :-/

Nick

[molten]

The friction plate is thicker than thole one but I put that down to being new. Gap behind pressure fingers was fine but when
Cover was fully bolted down, the gap was only 1mm.
What should gap be?

I can file the splines boss down a bit as its a little longer than the original. Would that help?

Also the splines boss at the back of the plate (toward flywheel)  is not flat like the original. Will this make any difference?
Concentricity: check to see how much ovality on the turn of the flywheel.

Thanks for help

[jaybee]

Your clutch driven plate and pressure plate appear to be incompatible. I also agree that the driven plate may have been fitted the wrong way round (i.e. flywheel side is facing the gearbox), but I have never seen a gap between the pressure plate and the flywheel when the driven plate is fitted the wrong way round.

Still don't understand you 'concentricity' problem. Where are you placing the finger of the DTI? Is it on the rim of the flywheel? If so, you may have the wrong flywheel for the vehicle. Check how close a fit the flywheel fixing bolts are in the fixing holes of the flywheel. If they are a sloppy fit, this could be your problem. If there are dowels to locate the flywheel, how good a fit are they in their respective holes?

[molten]

hello fallas.
The drive plate is correct way round (says 'flywheel side' on it).
Concentrcity measured the may recomended on 1500 repair manual on page 12.
DTI is placed on the shoulder of flywheel just outside where the cover plate is bolted.

I think there are a few things contributing to this problem with the gap.
1) New unworn clutch plate (increased thickness making clamping pressure fingers move more when cover is tightened)
2) QH cover is not stepped at fix point as originnal - loosig another 1mm (see pics above).
3) Splined boss is white long (longer than typical).

Points 1 & 2 mean that more spring movement is occuring on the pressure fingers when tightening cover plate to flywheel. So i loose about 3mm here.

I have now shortened the splined boss (and it is still longer than original), refitted and now have 4.5mm between splined boss and back of pressure fingers. This gap will widen as new friction material wears, increasing the gap.
What I need to find out is what the gap behind the fingers to the splined boss should be (or should not be less than) so that the gears will still engage in drive.

Hope this makes sense :)

Thanks

[Paudman]

I'd take a guess and say that the driven plate is incorrect - in fact as you say it's from a Morris Minor I'd be inclined to return it to the supplier for a correct version. You're having to modify it during fitting, I'd worry this may cause problems later on when driving. To save having to strip the entire shebang out again later on, I'd buy another plate and fit it for peace of mind.

[Clive]

Colin, he needs the 10 spline plate in 7 1/4 diameter, something Triumph never used/produced.
The minor plate is correct BUT there may be issues between different manufacturers. Think 6 cylinder clutches, laycock v B+B.

Was the plate actually a GCP103
http://www.canleyclassics.com/searchforapart/?desc=CLUTCH%20PLATE%20SPECIAL%207%201/4%20X%2010%20SPLINE

[That Man]

Hi scott,

You appear to have a 1500fwd (front wheel drive) clutch cover, these use a smaller input shaft 5/8" x 9 spine and a smaller thrust bearing, so the inside diameter of the diaphragm fingers is smaller. Check this against your old cover.

As regards your run-out problems with the flywheel i would suggest removing the flywheel and checking every thing is scrupulously clean, how tight is the fit of the flywheel to the crankshaft? it's would be a good idea to put the dti on the rear of the crank just to eliminate any problem with the crank it's self. The concentricity of the flywheel is governed by the fit of the counterbore in the back of the flywheel to the seal diameter on the crankshaft, the dowel is only for angular location.  

Gordon

[molten]

the original clutch gear is borg & beck (driven plate and cover) and has a larger diameter opening for the gearbox drive shaft than the new QH cover as noticed by Gordon.

The new release bearing fitted is same size as the original, but going off what gordon says above, now makes me wonder about this too.

I am going to order the GCP 103AF clutch driven plate to make a direct comparison. I beleive this plate to be exactly same as a typical 1500 plate but with 9 splines, expecting spline boss to have same dimensions. I f the slined boss on this new clutch is dimensionally same then this should work with QH cover.

The driven plate (10 splines) I have has a larger diameter on the spline boss and I think that when the bearing presses against the pressure fingers, the fingers will not pass the larger diameter boss. However, If I had a Borg & beck cover as the original, I think it would have been fine but dont want to take any more chances.

So much for getting g/box back on.

PS: Just checked release bearing on both gearboxes and they are both same size.

>:( >:( >:(

[drofgum]

2597 wrote:

hello fallas.

...What I need to find out is what the gap behind the fingers to the splined boss should be (or should not be less than) so that the gears will still engage in drive.

Hope this makes sense :)

Thanks

Hi,
I don't think your worry is going to be engagement, but rather disengagement. It seems that you may find, if you install things as they now are, that there is insufficient motion of the clutch cover to release the driven plate.
                                                                      Good luck,
                                                                      Paul

[junkuser]

With the correct driven plate and the lands on the cover hard against the flywheel the fingers of the diaphragm should be pointing outwards somewhat.
I wonder if that cover is for use on a recessed flywheel.  Can't imagine such difference in thicknesses of driven plates.

Morris 1100 plate rings a bell as being interchangeable with early Spit with coil spring clutch but may be wrong there

[MarkB]

Here's a couple of pics of a Mk3 Spit engine. The first pic is the new set up using a marina new old stock clutch fine spline as I wanted to try out a 1500 OD box. The second was the original clutch. Your one looks way to close. The clutch bit when the pedal was a gnats of the floor. In the end the OD box was no good so replaced the lot with a new three piece clutch from Canleys. The clutch biting point is a lot further off the floor using their clutch. The new old stock clutch had about a mm or two more meat on than the new one from Canleys. Appears to me that tolerances in the clutch are critical as to the operation as the two new plate I used feel totally different.  

Mark  

[molten]

I have ordered another plate today (GCP103) and just hope its not identical to the one I have...Will soon see :-/

The QH clutch cover that I have has a smaller diameter at the pressure finger tips than you can see on MarkB pics above, so willsoon see if this is ok too.

Does anyone know if the pressure fingers are pressed down below the spline boss on th edriven plate in operation?

Thanks

[MarkB]

Hi
The clutch cover you have in your pics just looks like the wrong type to me. It doesn't appear to be deep enough.

Mark

[herald948]

cliftyhanger wrote:

Colin, he needs the 10 spline plate in 7 1/4 diameter, something Triumph never used/produced.

I think I'll have to disagree on this, as I'm almost positive that's exactly what the "Federal" specification 1973 and 1974 Spitfire 1500s used, since they still had three-rail (10 spline input shaft) gearboxes! The Roadster Factory shows that 7.25" 10-spline driven plate as GCP232...and available!

[Clive]

apologies. I should have added in the UK.
All sorts of odd stuff happened to export models :-/

[molten]

The black clutch cover is a 1500 clutch cover manufactured by Quinton Hazel. The 1300 clutch cover seen above does look deeper I must admit but I thing Nos items were.
We'll soon see, gulp.

[molten]

New couch plate arrived today and fitted like a glove!!!!. Trying to save a Tenner cost me £30... lesson learned. Get gearbox back in and install engine in Sunday.
cheers all

[Nick Jones]

If you were trying to fit a 1500 clutch to a flat flywheel then all is explained.  1500 has a "pot clutch" which needs a raised rim on the flywheel (5 - 6mm IIRC), so without that it will have been considerably over-compressed and probably bottom out before reaching the flywheel  - which it did.

The clues were all in your first post in fact - should have spotted it  :B

Nick

[molten]

Hi Nick
My flywheel does have a raised rim.

If I had used the original clutch cover (couldnt because of wear on th epreasure plates from bearing), then all would have been ok. The old cover has larger diameter opening and would have fitted around the larger diameter splined boss on the plate.

I could have turned the splined diameter down to 1 inch and shortened the boss height but couldnt be bothered really.
I will do this later and save plate as a spare.

Cheers
Scott