johny

So I guess its the bin for my little lot. Even the 3/32" needle rollers are special order from the far east and not available from normal bearing suppliers...

Im building up a collection of laygears with worn bearing surfaces but dont want to throw them. Sleeving them looks problematic as youve got to keep the end thrust faces plus the bore seems to be a custom size so anything you make and fit needs to be properly hardened☹️

Yes with a recently purchased car check gearbox and diff oil levels at the earliest opportunity as the capacities are small, leaks very common and damage due to lack of oil easily done....

Yes but no movement of the engine as a whole so you can fix your DTI to the chassis and measure the movement of the pulley as you press the clutch no problem👍

Any ideas for knackered laygears?

If possible I prefer sleeving of bearing surfaces as you then get a proper race which is through hardened and machined to very fine tolerance. Its what Ive just done on the mainshaft tip bearing of the OD gearbox Im preparing but unfortunately to do the same for its laygear is much more difficult (impossible?)...

no its alright as the clutch slave is mounted on the gearbox operating it shouldnt move anything other than the clutch thrust bearing and so through onto the crank and its thrusts. You just need to push the front pulley back, mount plus zero the DTI and press the pedal...

He says factory spec and that recommends 6 to 8 thou so reckon hes up to around 11...

We have a caged on the mainshaft tip and free rollers for the laygear and all would last much longer if they ran in proper inner and outer races as these would have a high quality through hardening. Ours run directly on quite large components that would be too brittle if through hardened and so are unfortunately only case hardened to a depth of a few thou☹️

Im really surprised because as both the mainshaft tip and layshaft have the needle rollers running on them directly I find that by the time the needle rollers themselves are worn the surfaces they run on are really shot. I have always thought this is because the needle rollers being a precision specialist component are likely to be harder than the other components. Its made worse by the fact the bearing surfaces are only case hardened (of varying quality?) and once worn through deteriorate rapidly. The layshaft can be readily replaced but the mainshaft tip is much more of a problem....

Why do you say that wear is accelerated? Is that wear of the thrust bearings or somewhere else?

I can confirm that copper grease isnt conductive as far as a multimeter goes anyway...

To be fair John this request from Dave was for our opinion and experience - we can all just read the manual for Triumphs recommended figures and of course theyre the best to stick to but this is not always feasible. Then as always the replies given can vary, and horrors sometimes even be wrong. so its down to the reader to weigh them up and come to their own conclusion with no come backs....

wow Kevin so you think Polybush and others would do better to use non stainless steel sleeves?

Yes the photos might not be so dark on paper although in many cases even the originals werent taken with enough light😒

Triumphs workshop manual is the bible. Can be found in paper or available to download free from vitessesteve.co.uk...

To add Steve, in case youre not sure, pinking is a light rattling/tinkling sound you can get from the engine and as Nigel (and Triumph) says you will hear this when accelerating in 4th on the flat but it should stop by the time you reach 2000rpm. Its usually worse the hotter the engine and if it doesnt stop then the timing is too advanced👍

I thought one of the great things with polybush was the stainless steel sleeve that avoided the problem of them rusting onto the bolt and having to be cut out. I would certainly be interested in any of the trunnion kits that has the original plastic bushes but with stainless sleeves so getting this benefit without the expense of silicone👍 Also David whats the way forward with the rotaflex bush kit now then? I think perhaps some measurements could be taken and a recommendation made that theyre not suitable for any car with less than a certain clearance between the wishbone and upright...

The steel tubes always rust on to the bolt but I cant see this being a problem (until strip down) as the bushes can still rotate freely on the tubes...

Thats an interesting point as I wonder how the crush tube length compares with the assembled trunnion? If its not slightly longer then its a clear indication something is wrong in the bushes/seals/plates because they will get clamped and mashed by the movement of the upright and wishbone...

I suspect, as Doug indicated previously, Triumphs end float limit is more to do with minimising conrod to piston misalignment than stopping the thrusts from falling out....

If somebody can mic up a main bearing cap axial width for me I should be able to give a pretty good estimation of how much tolerance there is....

I think if its found that all bushes are going to be tight I would take some metal off each side of the upright...

Pity as a Herald would look so cool bouncing up and down on its air suspension US style but with its back wheels flapping like ears😁

Yes thats about what I got and I figure the rubber ring seals will crush a little so maybe a couple of mm total would do it?