pw58
Active Member
A friend's 966 has taken to puking oil out the breather when put in forward or reverse,any idea's .thanks Wayne
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cat966 loader leaks oil out of breather
- Thread starter pw58
- Start date
Nige
Senior Member
What series of 966..? C, D, H, ..? Serial Number prefix ..?
Which breather ..? Transmission..?
Which breather ..? Transmission..?
pw58
Active Member
sorry about that,the transmission breather on top.also it's a C with ser # 30k2577.Hope that helps.Thanks
Nige
Senior Member
That's the breather mounted on top of the transmission control valve case, correct ..? Does the breather start blowing oil as soon as you shift into gear or does it take a few seconds..?
Sounds like there could be a seal blown in the control valve assembly at the top of the transmission. It would need the cover plate taken off for a look-see. Maybe the oil drain from that area back down into the main transmission case is restricted. Does the transmission work fine, clutches not slipping, slow to engage gears, anything like that ..?
Sounds like there could be a seal blown in the control valve assembly at the top of the transmission. It would need the cover plate taken off for a look-see. Maybe the oil drain from that area back down into the main transmission case is restricted. Does the transmission work fine, clutches not slipping, slow to engage gears, anything like that ..?
pw58
Active Member
It appears to have just started to doing it,and the oil startsas soon as it is put into either gear.Other than the oil leaking the transmission operates fine,no noticeable shifting lag slipping ,etc.Regards Wayne
Nige
Senior Member
I think it may be worth taking the top cover off to have a look inside. Maybe something's blocking the drain port back down into the transmission case, either that or it's blown a seal up in the control valve.
pw58
Active Member
I,ll take a look when it warms up some,thanks Nige
rare ss
Senior Member
sorry to ask the basic question but is the oil level ok, not overfull with a sudden loss of Hyd oil?
pw58
Active Member
that's correct ,no loss of hyd. oil
Nige
Senior Member
You could try cranking it up while you have the cover off, but make sure you have something installed in its place like a piece of perspex so that you don't get a bath. That might help you see where it's coming from.
The control valve will always lose a certain amount of oil when the transmission is in gear. That oil will drain back into the transmission case. So the only way to pump oil out of the breather that I can see is that either the oil drain passage back into the transmission case is partially or completely blocked, or the valve assembly is leaking so much when the transmission is in gear that oil that the drain cannot cope with all the flow and so blows the rest out of the breather.
The control valve will always lose a certain amount of oil when the transmission is in gear. That oil will drain back into the transmission case. So the only way to pump oil out of the breather that I can see is that either the oil drain passage back into the transmission case is partially or completely blocked, or the valve assembly is leaking so much when the transmission is in gear that oil that the drain cannot cope with all the flow and so blows the rest out of the breather.
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pw58
Active Member
Hey the plexi -glass is a good idea.I'll try that next week when I'm in the shop .Thanks again Nige !
Nige
Senior Member
Drill some holes in it and bolt it to the top of the tranny where the cover was removed. If you don't and it catches a good spray of oil from underneath it could likely blow it clean off. Not good if you have your head close to it at the time ...!!
wsw
Well-Known Member
If it is leaking out of one of the holes in the top of the valve body see if you can relocate the breather so not to get direct shot of oil. It would take alot to plug the drains back to main case. ( chances are it could have broke a modulation spring in the valve body ) you get it working keep an eye on temp a that oil could be oil that should go through cooler