15 replies to this topic

[allaggro]

Hi, I am having trouble with my gearbox making what is best described as a band saw whine when driving under light throttle.
The engine is an 18000 mile 1275 and in all other respects performs faultlessly, the gear change is good too. I was worried that some thing was being chewed
up so I removed the power unit and separated the gearbox from the engine. I was expecting the fault to be obvious as there is alot of fine aluminium swarf in the oil film on the inner casings etc.
I honestly do not know what is wrong as every thing I checked looks perfect and there appears to be no contact between any gears or casings.
Your help on this is much apprieciated.

Many thanks Dan

[AndyMiniMad.]

Sound like the main shaft double roller bearing is at fault here. Its very hard to see anything wrong with the gears all fitted. But the normal fault is the plastic caseings which hold the ball bearings in place crack and split. this causes the bearing to whine when in use.

[allaggro]

Hi, thanks for the quick reply, does this bearing failure normally give rise to the swarf that I have?, I also had a reasonable amount of steel swarf stuck to the sump plug!

[Gulfclubby]

If the engine has been completely rebuilt only recently, some swarf is normal, actually. That's why you should change your oil all the more often on a new engine.

[new_zealand _minis]

i had this noise in my metro . then it went bang . smash the main bearing on the shaft and ball bearing go stuck in the diff


the bearing was pllit and was just sitting there doing nothing

[Jackamilf12]

This thread could be of use...
http://www.theminifo...whining gearbox

sounds like a similar problem.

[Guess-Works.com]

Pictures would be good...

[allaggro]

Thanks for all the advise on this one guys, I have checked the drop gears and they all look good, I will assemble the gear case back onto the gearbox tomorrow and measure the end float in the idler gear. The outer thrust face for the idler gear on the case is recessed by a couple of millimeters, is this normal or should it be totally flat? The actual surface is not rough or burred up at all. Finally does any one know what the end float should be?

Many thanks Dan

[AndyMiniMad.]

Ive had bad problems with my idler gears so im not the best one to give advise on this. But im fairly sure it should be around 4 thou. Im a bit concerned about the case though. a couple of mill you say! !It should be totally flat. sounds like the shim has eaten the case. very bad...

[AndyMiniMad.]

Mine looked like this....



It should look like this...



I eventually ended up with these.....Problem solved...

[allaggro]

Thanks for that, do you have a photo of the face inside the cover, the face on my gearbox is flat....thank goodness!!

Dan

[AndyMiniMad.]

this is the only one I could find. It shows a bit of the damage caused by my idler gear. This transfer case was used again as the damage was not too bad.

[allaggro]

Thanks mate!!!!!!!!

[allaggro]

Today I reassembled the clutch housing back onto the gearbox to allow me to check the end float on the idler gear, there is only about 3-4 thou clearance and it's bearings look good so I think that I can safely eliminate that as the cause of my noise.
The rest of the gearbox is currently in the hot wash tank being totally cleaned up before I delve into it's innards!!
I still can't believe that a gearbox can make a noise like this one does with out any obvious issues!!!!!!!!!!!!!

[ashleyread1]

Hi all, 

 

so i am having a knocking noise in my transfer case. i am changing most of the parts that could be causing this. however i have broken the plastic casing for the roller bearing and i do not have a clue where i can find one. can anyone point me in the right direction?

 

Thanks