johny

Theres some experts on here who Im sure will be able to tell us for sure....

Roger is the original inner spacer (0.210") standard? It doesnt look like the item shown in the manuals....

Roger, what are you going to do with the layshaft? If its in pretty good shape maybe best to reuse it as the pattern replacements dont always appear to be very good in that their surface hardening is poor so the rollers wear through it quite quickly.....

Its not so much of a weak point in your gearbox as its a vast improvement on the much smaller bearing used in my 3 rail unit. I think with yours the layshaft bearings are probably the weakest area as they are the same in both types of gearbox and certainly undersized for the 2L six.....

Thanks. Ive attached a page from the TR7 manual that shows the single rail internals (presumibly the same design as those used in other models) and as you say it looks like there is room for a longer bearing. Maybe the original idea was to ensure there was sufficient space for slight variations in the two shafts positions due to case casting differences, thermal expansion, bearing wear etc. Triumph TR7 gearbox.pdf

Hi Roger, you show the dimensions in mm but isnt it an imperial size bearing?

but thats the point because you cant guarantee more expensive means better quality - I believe theres a very limited number of companies manufacturing spares for our cars now as theres just not sufficient demand so often theres just one supplying a particular item and you can pay a lot or a little for it but in the end get the same thing!

yes Id even pay more to get better quality parts but market economics seems to dictate that its a race to the bottom cos you never know if the higher price youre paying equals a more reliable product.....

Ha, so you could replace the seals thinking it best when changing to silicone only to have the new ones fail cos theyre rubbish!

Suppose it must depend on the seal rubber type or age then as some seem to accept a change of fluid without any problems.....

Soft seals? Surely they must have started leaking then?

I agree. Its better to go by the noise made when running ideally comparing it with another car with the same engine in known good condition. How many miles is your car showing Nathan? If you are convinced that the bearings are worn you could just change them for standard size replacements possibly doing it with the engine still in place. Regrinds are usually only necessary after high milages (and one or more std bearing changes), if the std bearings arent changed in time and have failed completely, lubrication failure for whatever reason....

I find my hand occasionally slips off a small knob mid change and then the retry causes some serious crunches. Its not just the size but the surface texture as I found the original and wooden replacement a bit slippery....

no OD on mine but no need as now Ive got 6 speeds👍

Wish it gave me 6 gears! I had a wooden one before but as I say it was quite small where as now Ive got a big one and its a much better fit in my hand (perhaps I shouldnt have started this thread). The top of the new one is curved so wouldnt take anything stuck onto it and if I try levering it off I might ruin the whole thing.....

My original cap has a small hole in it next to the grommet hole to do as you say Colin. Maybe the repros dont have this and just possibly the grommet seals well enough to allow a vacuum to be pulled on engine cooling.....

Sorry couldnt resist the title as have just fitted one of these to my Vitesse for 7 quid. I find it a big improvement at 51mm in diameter cos its so much easier to grip and avoid poor changes. I know the purists probably wont like it (even I might do something about the number of speeds shown) but I think anything that gives my gearbox an easier life is a good idea...

Think Paul had the audacity to introduced the two items in his original post😲 Unfortunately we dont seem to have had any comments on mine, Dave's or John's suggested causes.....

if its real dirty like mine was you cant see the level☹️

How did it come up Doug?

That is surprising! Mines a repro and been fine but then it never gets hot enough to deform - did you have a major engine overheating incident?

the good news is that any air getting in still has to pass through the filters👍 Think the cap to the overflow bottle was originally aluminium....

yes theres certainly a lot of 'dire warnings' floating around these days😱

probably how Id do it, thanks

That sounds like a pretty good life span. What procedure do you use for the fluid change overs and do you replace all seals?