Hi Malcolm,
The arm, like all the other conversion parts was supplied new for this particular engine/gearbox combination less than 2000 miles ago. I have been in touch with the supplier and will shortly remove the engine to see what is amiss.

Andy

Hi Andy,

I have read elsewhere of problems like this arising from wear in the bearing carrier arm pivot holes and/or its bolt. However, if you have only recently assembled it, I think you would have noticed any such wear while doing so.

Are you sure you have the correct arm?

Malcolm

Hi Andy

The engine has been out so many times, how annoying, but I think you are right and the problem is in the pivot bearing/clutch actuating arm area. It is interesting no one else is reporting the problem, others must have gone down the same route as you, so it could be just a one off.

Too far away to help regrettably, let us know how you get on.

Kind regards
Trevor

Hi Trevor,

I think the misalignment must be due to the pivot bearing/clutch arm combination. The bell housing and engine back-plate are the same ones I used with my previous Magnette engine and clutch. The only problem I had then was a slight tendency to clutch slip on first engagement.

When I fitted the 1800 engine I decided to change to the MGB diaphragm spring clutch and Peter Gamble supplied a new pivot bearing and an MGB clutch arm to suit. It was only after that the problems started. You may remember I found that the slave cylinder push rod was not acting perpendicular to the clutch arm and I had to add a 5mm spacer under the slave cylinder to correct this. There also appeared to be too much throw on the clutch arm so I fitted a stop under the pedal to limit this.



I did discuss these issues with Peter but he said he had not heard of them before.

The inspection camera pictures are not really good enough to properly understand what is going on. The field of view is too narrow and manoeuvring the camera too hit and miss. It does seem clear however that the carbon thrust approaches the pressure plate at an angle and hits it first at the bottom, not realigning itself properly when it does so until considerable force is applied.

I cannot really visualise what could be causing this, so I am afraid the only way to resolve it will be to have the engine out again!

Andy

Hello Andy

Been away for a couple of days, just wondering if this misalignment may be part of the problem with the vibration and gearbox height. is the bell housing incorrectly machined, face to face, which would affect the drive line, or is the error in the pivot bearing? either way it isn't right and needs to get sorted. Perhaps Peter Gamble can advise, the misalignment looks substantial.

Trevor

I discovered that video files are not supported on this forum so for what it is worth I have posted the file here: www.flickr.com/photos/clacksman/

I was unable to get a better view by removing the starter, as the camera lead is bendy and difficult to manouvre, but I did establish that the carbon thrust bearing is not meeting the pressure ring in parallel fashion as it should.

The bottom of the carbon thrust hits the pressure ring first with a clonk, and it then takes considerable pressure to bring the two faces parallel (I used an 8 inch adjustable spanner as an extension on the clutch arm to do this)


Seems there is a problem of geometry here!


Andy
Edit: Seems the forum doesn't accept .BMP files either at the moment!