The Triumph Dolomite Club - Discussion Forum

Hello
I may need to look at a gearbox rebuild or purchasing a refurbished one. I am asking a recommended garage to look at the gearbox for me, it worked OK last time I drove the car, all gears select OK including overdrive, but it seems pretty noisy, a clattering noise on acceleration, a Triumph specialist said this sounds like the layshaft. I'm not sure a worn layshaft would sound like that...? Obviously it's not easy to say whether I should ask the garage to rebuild my gearbox without knowing exactly what it wrong and therefore how much repair will cost, but I wonder if a refurbished box may be cheaper in the long run and should be pretty sorted. I see Fitchetts do an exchange for £350, I think Quiller also do them. Has anyone had any experience of buying boxes from either? Thanks!

I got some solid advice about just this subject in this thread, might be a useful read?

I have a spare gearbox I'm thinking of having reconditioned. I can deliver it and collect from the company I want to go with. Note this is an 1850 single rail overdrive.
£700 - £900 including vat.
My only problem is getting the old one out and the new one in afterwards.......

Layshaft bearings are a quite a common general failing part in a lot of gearboxes, so it tends to be what people come up with as an easy diagnosis.

However on Sprint boxes Ive found layshaft bearing failure to be rare. The bearings are discreet as opposed to a collection of random rollers. So they tend not
to jam up and slide as opposed to roll and consequently need a larger lump of debris to make them stick and fail.

The small car boxes are a different thing altogether. The layshafts are of dubiously variable quality and run on a bunch of needle rollers which need little to make them stop
rolling and slide, so they soon wear and cause a lot of debris from themselves and the layshaft itself, resulting in horrible rushing noises and a nasty mess of filings in the
lubricant, which soon takes other bearings down too.

Layshaft noises will occur in all intermediate gears or even worse case in neutral with the clutch up. The noise is diminished when running in direct top gear.

Sprint boxes usually make noises from either the input or main shaft bearing.

You can rebuild a Sprint box but sometimes the bearings are a tight fit on the mainshaft, and Ive had to be pretty brutal having only a big hammer to drift the shaft through the bearing. The manual says use a special puller - good luck with finding one of those. I havent.....

The bits cost about 300 quid to do it properly and its easilly a day's work. Obviously folks who do this professionally can save by bulk buying the parts and do it quicker with skilled techs and better tools.

When my life was tougher I would occasionally do a box rebuild and sell them on. Its a hard way to make a crust....and what do you do if it goes wrong? You either have to do the whole thing again for nothing....or feel a git for letting folks down. No easy options....and luckilly I have never had to have a Sprint box back.

Then there is the overdrive....what do you do with that? A whole other thread...

Jonners

Hi thanks for your thoughts, I have been trying to reply to say this for days but have been getting an error message when trying from my mobile. I guess I will see what the garage suggests regarding whether to repair or replace, my gearbox will have to come out ither way although maybe they will have some ideas about the cause by listening to the noise haha! Refurbed boxes seem to vary in price I notice, from £320 to a grand. Maybe you get what you pay for I don't know. Shame I can't do this level of work myself.
Chris.

I personally had this option but decided to go down the rebuild route, albeit I got someone to do it. That person was Mike Papworth. He knows the Triumph boxes vey well and picked up a few bits on mine which I hadn't thought of. Like the hole in the case which could have caused some damage. I then had the case replaced but the internals were original, a mixture of new and used parts.

Yep - I would second Mike Papworth as a good man to use - very friendly and helpful and knows more about Triumph gearboxes than anyone else alive - he has reconditioned two boxes for me (a big six box and an 1850 box which he upgraded all the bearings in so that it is good for 200bhp) both recons cost £650 each - you would do well to find anyone else that does a better job for less money. Mike will only use good OE second hand parts as he doesn't rate the modern remade parts. He's always busy so there can be a month/6 week turnaround but he's also pretty flexible...

One advantage of a refurbed box is you could sell the faulty box to offset the cost. Even a faulty Sprint box has value.

Sorry Swifty but I really dont see how you can uprate the bearings and expect a small box layshaft to handle 200 bhp.
The TR7 version was supposed to have uprated bearings....an extra ball in the race at both ends IIRC. The layshaft still has needle rollers. I guess you could machine the layshaft out to take the bigger cages and if you got that done for 650 quid then fair play to Mike that was a deal...

I suspect you have the best layshaft (not a rimmers cadbury's flake one) he could find and OE needle rollers.

Mike like all of us has to eat....

Jonners