Rectifying wear in clutch withdrawal levers

[John P]

I'm probably over planning this but, as I will be removing the engine and gearbox on my Ulsteroid, I am thinking about the various jobs it may be worth tackling at the same time.

I'm actually intending to fit lip seals to both the rear main and also the input shaft of the 3-speed gearbox but I was also considering if it's worth trying to eliminate some of the wear in the clutch mechanism to hopefully get more did-engagement.

I have previously fitted new toggle levers and corrected the wear in slots where the toggles locate but I know there is also wear on the thrust bearing housing both where the toggles press and also on the lugs which contact the withdrawal levers.

In addition there is wear on the ends of the withdrawal levers (BH82 and BH83) themselves.

Has anybody built up the worn areas of the withdrawal levers and the filed them back to the correct profile and / or on the thrust bearing housing where it contacts these?

Any advice would be appreciated.

John.

[Nick Lettington]

None of the above, but when I start putting the Silverstone together I plan to incorporate the rollers described in the 750 companion.

[Charles P]

I did that with a 3 speed clutch release bearing and housing, but later converted to using a 4 speed release bearing with my 3 speed box. I now wonder why people bother with the three speed bearing.

Charles

[Ray White]

I have fitted the rollers as mentioned above. I seem to remember I cut up an old 1/8" drill bit. It was a long time ago but one of the best things I have done...

[Howard Wright]

Hi John

+1 for the 4 speed release bearing assembly.

I have a standard bearing assembly on my 3 speed RK and a 4 speed release bearing assembly on my 3 speed gearbox special.  I can’t quite understand why, but to me the 4 speed assembly provides a much better progressive clutch rather than the ‘switch’ provided by the standard assembly.

By the way, I use neither mousetrap springs nor a return spring on the 4 speed assembly relying on the standard pedal spring to hold the bearing against the hammerhead toggles. Terrytuned provided an excellent sketch of how to incorporate return springs in a recent thread on here and if you search you’ll find several ways of using either mousetrap springs or alternatives on a three speed clutch plate!

I would be interested in a photo of the wear you mention to the withdrawal levers.  I’ve not noticed wear on my levers although there was a little wear on the associated bearing surfaces of the release assembly.  I simply milled these areas flat….there seems to be quite a lot of metal here!

Hope this helps

Cheers

Howard

[John P]

Thanks for the input and the comments about wear in the toggles but my issue is with wear on the ends of the withdrawal levers which are the ones attached to the clutch cross shaft.

Unfortunately I can't show any photos as the engine and gearbox are still in the car awaiting some reliably dry weather as I'll have to do much of the work outdoors.

Howard - I can see what you mean about milling the abutment faces on the thrust race housing but I guess this would actually reduce the total clutch dis-engagement.

I have hear of people getting more clutch pedal movement (which would off-set the wear and allow more clutch did-engagement) by, presumably, grinding away some of the casting which the pedal hits when fully depressed.   To be honest I can't really visualise this and in any case I'd be very reluctant to do so.   I'd just hoped to get a little more clutch dis-engagement to help getting into first gear without grinding the gears.

I don't really want to mess around with the toggles again as I took ages to get them even and in the correct position relative to a straight edge across the bell housing.

John.

[Terrytuned]

Fitting a 4spd bearing would solve all the problems Terry.

[Charles P]

John, Is the clutch dragging, even when the pedal is fully depressed?
Has it always done this?

If so my first check would be the length of the splines on the driven plate. Some were longer than others and a mismatch can cause a persistent drag that makes disengagement difficult, because the driven plate is always pushed onto the flywheel lining.
Don’t ask how I know this.

C

[John P]

Charles.

Yes it does always seem to be dragging and has always done so.   Originally I thought it was due to wear in the toggles and particularly in the slots where they locate but having tried to rectify this the problem still persists which is why I started to consider wear in the thrust race housing and the clutch arms.

When I get the clutch apart I'll measure the spline length but in the absence of anything to compare it with I'm not sure how I could interpret the result.   Does anyone have a driven plate they could measure?

I guess it would have to be too long to cause dragging so presumably a small amount could be machined off the end but, without being sure that's definitely the cause of the problem, I'd be a bit reluctant to get this done.

John.

[Dave Mann]

The original 3 speed toggle levers were a different shape to the 4 speed      whilst the reproduction 3 speed toggle levers are the same as the 4 speed. I'm not a fan of the 3 speed clutch arrangement because all the wearing faces are in contact all the time thanks to the clutch pedal spring whereas they are held apart on the 4 speed.