Torsion bar reaction plate

[ALAN COCHRANE]

Christopher

Thanks for the info. I've decided to stick with the 9.5" spring clutch. I'm actually quite happy with the clutch action I had even with the screeching problem. It would also mean that it would be another part which was original spec.
I was very impressed with the gearbox specialist's knowledge and the fact that he seems to have diagnosed the problem purely by a photo and a description. The spiral scratching is virtually invisible under normal light and as a result was very sceptical before taking the photo.
Otherwise I would have replaced the clutch and release bearing and ended up still having the same issue.

Cheers

Alan

[christopher storey]

Alan : just to be clear, your existing spring clutch is 10 inch looking at your original photo with the clutch cover in situ. It was only the diaphragms which came as 9.5 AFAIK

[ALAN COCHRANE]

Christopher

Yes my mistake.

Alan

[ALAN COCHRANE]

Just an update on the gearbox input shaft. I've just had it confirmed that the bearings including the input shaft bearing showed signs of substantial wear and are being replaced. So my initial suspicion of excessive play seems to have been borne out.

Cheers

Alan

[64etype]

...just a side thought (and you probably are aware of this). There are two ways (as far as I know) to adapt an all synchro transmission to a 3.8 engine. One is to replace the 3.8 flywheel, starter and bellhousing with components from a 4.2. The second method is to machine the large hole in the bell housing to 4.2 dimensions, such that it will accept the larger flange on the 4.2 transmission. In the latter case, the original 3.8 flywheel and starter are retained.

The depth of the newly machined hole is critical as the outer race of the large bearing at the front of the transmission must have a slight clamping force on it to keep it from rotating in the recess. In other words the depth of the newly machined recess must be exactly as for a 4.2 bell housing. For peace of mind, I would check as to whether you are dealing with a 4.2 bellhousing, or a machined 3.8 (or perhaps something else that I am not aware of).

I employed the latter method and the machinist cut the hole too deeply...even after I warned him about the critical nature of this dimension. Fortunately, I caught the error when I examined his handiwork. The hole had to be TIG welded, and machined again.

[MarkRado]

Christopher,
always thought about converting to diaphragm clutch myself;
beside om drilling- does this involve a different slave cyl and other work as well?
TX
Mark

[christopher storey]

Mark : as far as I know , there is no mandatory need to change the slave cylinder , lever arm, or release bearing when going from a 10" spring clutch to a 9.5 inch diaphragm, but it would obviously be sensible to fit at least a new release bearing

[64etype]

The release bearing for the diaphragm clutch has a different offset than the one for a coil spring clutch in order to compensate for differing clutch cover thickness. So it is mandatory that the correct release bearing be installed. The other components are unchanged.

[MarkRado]

Thank you all,
next time the engine is out I'll give it a try! Never over, never in