Should I refurb the box?

[cleverusername]

I have the Sprint engine and gearbox split in the garage. I am going to change the crank and check the bores etc but while I am at it, should I refurbish the gearbox?

The only test I have done on it was on the drive, it goes into all 4 gears ok and and reverse. Couldn't get enough speed to test the overdrive. However there was a whooshing noise, best I can describe it. Sounded like a washing machine running. Also I don't think I got up enough speed to pick up any whines.

So would it be best to leave it alone or would it be worth attempting a rebuild? How great is the risk I could knacker it attempting to rebuild it?

[yorkshire_spam]

I'm not sure about Sprint boxes, but for the single rail smaller triumph manual box sourcing quality bearings etc is now a nightmare and costs a fortune.
So I'd say if you do strip the box down be VERY VERY selective about whether you use new parts or re-use the old ones. (I've found front/rear gearbox bearings used originals were in better shape than NEW ones!)

[Carledo]

I used to rebuild Triumph gearboxes quite a lot back in the 80s when I had my GT6. I no longer do it. It's a relatively complex box for a beginner to attempt and the parts situation has gone from poor to dire, prices have gone through the roof and quality is in the basement. Even back in the day, I found it desirable to have a handfull or more of parts gearboxes as a pool for rebuilding.

There are a few "habitual" trouble spots on the box, chiefly the laygear bearings which affects ALL Triumph boxes, large and small, but they will run noisy like this for a good long time and fixing them is only a temporary cure. The one thing I WOULD check REALLY CAREFULLY is the clutch operating cross shaft as this is a pain to do at best and impossible with the box in the car. Otherwise the gearbox is fairly robust. Change the oil and test it driving properly. If it aint broke..........

Steve

[cleverusername]

I used to rebuild Triumph gearboxes quite a lot back in the 80s when I had my GT6. I no longer do it. It's a relatively complex box for a beginner to attempt and the parts situation has gone from poor to dire, prices have gone through the roof and quality is in the basement. Even back in the day, I found it desirable to have a handfull or more of parts gearboxes as a pool for rebuilding.

There are a few "habitual" trouble spots on the box, chiefly the laygear bearings which affects ALL Triumph boxes, large and small, but they will run noisy like this for a good long time and fixing them is only a temporary cure. The one thing I WOULD check REALLY CAREFULLY is the clutch operating cross shaft as this is a pain to do at best and impossible with the box in the car. Otherwise the gearbox is fairly robust. Change the oil and test it driving properly. If it aint broke..........

Steve

That was what I was afraid of, complex job and crap parts. I think I might just leave well alone.

[ToledoZombie]

I have the same issue on mine, 1st 2nd and 3rd are noisy as hell.