MG4 Reduction Gearbox Oil Leak

[SueH]

Are you able to give me his name, as it would be good to quote it in the email I am just about to send to my dealer (given no response yet to my phone call.)?

 

[cbowen]

Thing is, these things often get resolved and i guess it depends on your tolerance level, and if you have another car to tide you over, or they give you a free loner. It does take the shine off, but in all likelihood, it will get resolved and in a few months and this board's comments will see that leak in the rear view mirror.
Fledgling cars can have issues. I'd guess buyers' next summer, say, will be blissfully unaware of this stuff.
If you want a laugh, google image 'MINI paint rubbing' and see images of the inner door shunts of 3 door MINIS of the latest incarnation (F56 model, 2014 onwards). Now, that STILL continues, 8 years on! I've even done 'experiments' asking what must be easily 25 people in supermarket carparks with 3 door F56 MINIs... and they've ALL had it! Even someone with a 6 month old EV version who I asked last week. Not rubbed through like in the google image photos of course, but the beginning signs were there.
(I knew about itmyself before I bought it and got these ppf strips early on which some guy sells which covers the area)

My 18 month old Mini Electric had this issue!

 

[Fogey]

My 18 month old Mini Electric had this issue!

Somehow reassuring - did BMW fix it with a modified breather?

 

[Les burrows]

If there is indeed a modified breather arrangement, I'm wondering whether it is effectively an extension to raise the height of the point where it actually vents to atmosphere?

Alb, I hope your not suggesting a Chimney ???

 

[donerkebab]

Sometimes its good to have a break then come back a few days after:

So if it is actually the breather pipe being the issue.

My questions to MG would be now
- in the meantime how its it safe and responsible to the environment to still sell cars that are still leaking oil and what is causing the discolouration?

- which shipments will have the new breathers installed in place?

 

[Ian Key]

Alb, I hope your not suggesting a Chimney ???

 

[Deleted member 10041]

Hmm - discoloured oil, possible transmission oil starvation whilst driving at 70mph?

100% this, discussed this with the fleet manager (ex head mechanic) at my work. His best guess for the grey oil was wear from metal components and he would advise not to drive it. He also said he wouldn't commit to guaranteeing there wouldn't or couldn't be any potential side effects to underfilling oil levels

 

[ukflyer]

Had a thought. If the oil is grey (milky) that would indicate water (think ice engines with blown head gaskets). Perhaps there is water ingress into the diff, via the breather, which then raises the level of he oil, causing it to overflow, back out of the breather. Perhaps it should have a one way valve which is not working.

 

[Les burrows]

View attachment 12047

Funny Ian but I was thinking more like this to be sure it’s high enough really
Les

 

[Les burrows]

No but seriously folks, we are not out of the woods with this yet IMHO, great the dye that was put into crawfyp car has showed it’s coming out of a breather but the question remains whats causing it, reducing the oil levels has not appear to cure the issue and I don’t agree that’s the right way to go anyway, and there could be a number of reasons for the oil discolouring crawfyps dealer as done a good job with the dye but, we have as yet had nothing come out of MG about what is to be done about the issue, perhaps there is some water Ingres getting in some how as mentioned by ukflyer above but MG are saying nothing at all about a cause or a cure from what I’m reading.
Les

 

[Avro]

Here is a thought, pondering the facts as we know them, it occurs to me very likely the breather pipe will have some sort of check valve to prevent oil mist (droplets) from being ejected in normal use. If indeed the oil level has be too high forcing oil out of the breather it could damage such a valve which would explain why some cars respond to an oil decrease and some don't.

 

[Ian Key]

Has anyone got a picture of the breather pipe?

 

[Fogey]

Has anyone got a picture of the breather pipe?

There's this picture from post 346 (thanks Hallix73):

https://www.mgevs.com/attachments/9f513a1d-9b3d-4cc1-b801-32e55b475786_1_105_c-jpeg.11933/

I'm sort of assuming that the small "chimney" at the top right would be a breather.

 

[siteguru]

That "hat" (the black thing on top of the casing on the right) almost looks like a pressure relief valve.

 

[Fogey]

That "hat" (the black thing on top of the casing on the right) almost looks like a pressure relief valve.

Yes, it does, so maybe the breather is somewhere else - or possibly it performs both roles.

 

[Hallix73]

That "hat" (the black thing on top of the casing on the right) almost looks like a pressure relief valve.

Yes defo that which is also the filler cap as well. You can see the drain plug below as well. My guess it will have a sort of gravity or light spring non-return valve incorporated into it.

 

[Alb]

The breather would normally be at the top and it wouldn't have a check valve because it has to pass air in both directions. There is no pressure relief valve because such a device would only be required if the gearbox was designed to operate at pressure in the first place.

 

[Deleted member 9909]

Quote
"Breather allows the transmission to breathe air when the air inside transmission expands or contracts due to heating and cooling of lubricating oil during vehicle running. Breather allows the hot air to escape and cool air to enter into the transmission to prevent overheating issue"

 

[Lovemyev]

Water ingress with oil, usually gives it a creamy beige colour.
Grey coloured oil would indicate a sign of metal / alloy is present.

 

[Avro]

OK check valve maybe the wrong term here but some sort of baffle that would be designed to pass air not great globs of oil ....all speculation of course