Technical gear box oil

[david295]

mk2 y reg 1.2 8 valve
I want to change gear box oil, i dont think its ever been done, is it a good idea to do it, will it benifit from it, and what oil do i need and how much oil for a full change

 

[DaveMcT]

https://www.fiatforum.com/punto/249434-how-do-i-change-gearbox-oil-punto-55s.html

I (and Ziggy) suspect the gearbox will benefit from being slightly overfilled so the input bearing is less likely to be dry when starting the engine. I believe jacking the front of the car when filling to slightly raise the filled oil level will help. Of course serious over-filling is not good so a 1:3 hill would be overdoing it.

Dont torque-wrench the fill & drain plugs use common sense to get them tight but not rammed up solid.

 

[m20b25]

You will need 75 synth gear oil, approx 1.75 litres of the stuff. The gearbox will be smoother and quieter

 

[david295]

You will need 75 synth gear oil, approx 1.75 litres of the stuff. The gearbox will be smoother and quieter

thanks for all input, i have just completed the gear box all change, and what a difference it makes, am going to get my crank shaft oil seal done tomorrow, then i will give it a oil change with good quality oil.

 

[DaveMcT]

You may need to drain out all that nice new oil when you do that seal. Clean the casing and used a clean catch bowl so you can re-use it.

The input shaft seals fail because the bearing behind has failed. Its a common standard bearing, but the gearbox has to be partly stripped to do the job. There is a guide by Mr Wild

Replacing the seal only is pointless as you will be doing it again in a week or two and replacing the oiled up clutch.

 

[david295]

You may need to drain out all that nice new oil when you do that seal. Clean the casing and used a clean catch bowl so you can re-use it.

The input shaft seals fail because the bearing behind has failed. Its a common standard bearing, but the gearbox has to be partly stripped to do the job. There is a guide by Mr Wild

Replacing the seal only is pointless as you will be doing it again in a week or two and replacing the oiled up clutch.

i might be wrong when i said crank shaft oil seal, the oil leak is coming from timing belt end

 

[Ziggy122]

Mine Box was full (at the filler hole point)
I put my car on the drive which is quiet slanted - and added about 100ml extra into the box
It means the bearing might have more of a chance of been in constant Fluid

But with the g.box Dead AGAIN! :bang::bang: I'll be double checking my level when it comes back

Ziggy

 

[DaveMcT]

i might be wrong when i said crank shaft oil seal, the oil leak is coming from timing belt end

Sorry I cant read

But regardless of the engine check that gearbox bearing when you do the clutch. If there is ANY doubt about free play change the bearing (and seal).

The crank seal at front of engine needs the cam belt off.

The crank seal at back needs flywheel off and I believe a set of new drive bolts (others will know). Use a self tapping screw into the old seal to extract it.

 

[flisko]

https://www.fiatforum.com/punto/249434-how-do-i-change-gearbox-oil-punto-55s.html

I (and Ziggy) suspect the gearbox will benefit from being slightly overfilled so the input bearing is less likely to be dry when starting the engine. I believe jacking the front of the car when filling to slightly raise the filled oil level will help. Of course serious over-filling is not good so a 1:3 hill would be overdoing it.

Dont torque-wrench the fill & drain plugs use common sense to get them tight but not rammed up solid.

why would that be bad? more oil more smoother gear change?

 

[fingers99]

For the bearing/seal thing, it's a manufacturing issue with the Punto line of boxes, I'm pretty sure. They bought a big batch of under specced bearings.

The issue is just about unheard of on Centos, unless they're fitted with Punto boxes......... join the dots.

 

[Brendan W]

If you mean why would overfilling be bad it's probably going to mean more heat is generated in there. Gearboxes generally are splash lubricated not submerged in a bath of oil so you fill until everything is being splashed and no more.

 

[fingers99]

Overfilling doesn't do any good -- heat, power loss, and the excess will try and get out somewhere.

Just about all production car boxes are splash. Exceptions are some Toyota and Porsche boxes which are pumped. I think some Suzuki bikes, too.

 

[flisko]

what kind of overfill are we talking about here like 0.1L, 0,5L ?

 

[Brendan W]

Not an exact science. I doubt very much that the box would notice an extra 100ml or two. 500 would be pushing your luck imho - if you could manage to get in in there in the first place.

 

[oldhammer]

get car on level ground ,and then theres not much chance of overfilling is there?

 

[flisko]

Not an exact science. I doubt very much that the box would notice an extra 100ml or two. 500 would be pushing your luck imho - if you could manage to get in in there in the first place.

easy on a hill

 

[Brendan W]

Gearbox is at the other end though

 

[flisko]

he was getting suitcase for his gf

 

[Brendan W]

I thought it was the manure for Betty's Roses.

 

[oldhammer]

View attachment 138366

Gearbox is at the other end though

that pic wouid make a brilliant caption competition, :devil: