Cause of gearbox failure
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Cause of gearbox failure
well found the problem of the gearbox failure

the main shaft out put side nose needler roller where it sits in the first motion shaft the main shaft end was worn at the end some
0.9 of a mm & the needle roller was beginning to break up!

this would cause excessive radial loading of the area together with a naffed first motion shaft bearing. causing the input gears to fail

some one had been into this box before & ground the end of the shaft, as it must have mushroomed over & assembled it with a new bearing. a amature BODGE!

a disaster waiting to happen! with some extra HP


i tried to have this turned down and sleeved but to no avail as this was bone hard,

so hard if fooked! one of his diamond cutters up!
it needed grinding! & my good friend did not have the facility to do this i could have sent this away but at extra pounds..........

many options left but the easy way out is to ...............
strip an old good shaft out of a box for the purpose

heres a pic not a good one, but you may just see the wear!
in relation to the bearing.?

Edited by BENROSS on 21st Sep, 2005.

Good to see you have conclusively found the ROOT CAUSE of the failure.

I am sure the benross mini will soon be back, faster than ever!

you get the first go tom.

i suspect the gearing for the intended purpose in mind.

CHAV KILLER!
is still a TAD too short though.

Will have to see when you have it back together, I think it will be much improved over previously! Especially with the longer first gear and closer ratios for keeping it on the boil!

Is this an A+ or A box? I've seen this happen in numerous A+ boxes, but very rarely in A ones. It seems as the A mainshafts are harder (especially the factory ones)

A new A+ main shaft is over ?230 i think whereas an A one is ?70. It'd be interesting to see if hte new A ones are as hard as the old ones as they are dirt ( too ) cheap really.

My expereince with this is that the lack of changing oil ( Not saying you've done this) speeds up the destruction of this little bearing

A+ gear set including layshaft and mainshaft assemblys, interested?

I was going to chuck it in the bin, but you posted this just in time!

Vegard i dont know the history of the box only i got told it did 64k
looking at all the other bits its superb to say the least.

i know the car got wrote off, makes you wonder if some one had not raised the boost etc in its past ?


sump nut pm sent buddy

the A box is 14mm on the end and the A+ is 18mm

it needed grinding! & my good friend did not have the facility to do this


Im a grinder and I work nights

Metro turbo weekend driver,Mini turbo in the making again!

dangerouse top guy pm sent

On shaft prep ground to .675"/carbide coated to
.720"/diamond ground and polished to .7085"

Better than new

Metro turbo weekend driver,Mini turbo in the making again!

Are you selling? If so, I'm interested :)

wow thats some cool work...

I'd of junked it in my ignorance that it was repairable!

Alex

AlexF

Metro turbo weekend driver,Mini turbo in the making again!

top job! Dangerous, what do you do for a job?

Team Racing

Cnc grinding in a coatings factory been their 20 years now

Metro turbo weekend driver,Mini turbo in the making again!

can you do metal spraying there buddy? Don't need anything done at the moment, just thinking for future projects

Team Racing