MG4 Reduction Gearbox Oil Leak

Took the words right out my mouth, probably better you saying it!

But hey it's not a big deal, just a minor niggle!!

Nearly 5 months now embarrassing
but it could be just a small leak that will stop after the oil level drop down to where it should be not a big deal as you said , take modern ice engines all leak from top cover because they are made of plastic , even on the more expensive cars .
 
but it could be just a small leak that will stop after the oil level drop down to where it should be not a big deal as you said , take modern ice engines all leak from top cover because they are made of plastic , even on the more expensive cars .
Sadly that is not the case as when the level drops down or is reduced from 900ml to 750ml or lower they usually still leak and in many cases the new 'revised' breather does not stop the leak also.
Also as @Leni16 suggests MG should be embarrassed. :sneaky:
 
Sadly that is not the case as when the level drops down or is reduced from 900ml to 750ml or lower they usually still leak and in many cases the new 'revised' breather does not stop the leak also.
Also as @Leni16 suggests MG should be embarrassed. :sneaky:
but if it is from the breathe 100 % there are ways , i have converted systems on cars with poor breather position which use to throw out oil and smoke on bends , you just make pipe longer going up then down then up again and vent it high and no oil will come out from there If its 100% from the breather.
 
Wouldn't a simple expansion tank with a baffle to slow the air down allowing the oil to drop out of the air flow work?

1677653489247.jpeg
 
but if it is from the breathe 100 % there are ways , i have converted systems on cars with poor breather position which use to throw out oil and smoke on bends , you just make pipe longer going up then down then up again and vent it high and no oil will come out from there If its 100% from the breather.
The point is it should be MG that fix it, it's there issue and it's been happening for months
 
The point is it should be MG that fix it, it's there issue and it's been happening for months
i know but if thay are that stupid not able to pin out and solve the problem id rather fix it myself than keep going back and forth to the dealer , its not a critical issue or one that can be only solved by them .
 
yes should work , if its the breather the problem
We believe the problem is the placement of the breather opposite the gear so that oil is flung into it, there is also speculation that foaming is an issue and so oil is travelling up past the breather and escaping.

We do not know for sure. Macadoodle has tried fitting a long pipe but still has leakage.

All of the conversation is neatly distilled here into 2,600 posts for your convenience. 😂

i know but if thay are that stupid not able to pin out and solve the problem id rather fix it myself than keep going back and forth to the dealer , its not a critical issue or one that can be only solved by them .
We have had one report of a motor fault with a dry gearbox and swarf, probably caused by an oil leak. Need more reports to be sure if this is more common.

For a long time I considered it a minor issue but it is months now and MG should have got to grips with it. Plus they are being obstinate about not proactively changing the breather setup and forcing owners to get the leak and send to dealer before attempting a fix that does not work in all cases (it does in some).

We have a mystery about why some people never get the leak, some have it fixed with the new breather and some not.
 
We believe the problem is the placement of the breather opposite the gear so that oil is flung into it, there is also speculation that foaming is an issue and so oil is travelling up past the breather and escaping.

We do not know for sure. Macadoodle has tried fitting a long pipe but still has leakage.

All of the conversation is neatly distilled here into 2,600 posts for your convenience. 😂
yes i went through it (not all but many pages ) not longer you need to do serpentine up and down to stop it .

We have had one report of a motor fault with a dry gearbox and swarf, probably caused by an oil leak. Need more reports to be sure if this is more common.

For a long time I considered it a minor issue but it is months now and MG should have got to grips with it. Plus they are being obstinate about not proactively changing the breather setup and forcing owners to get the leak and send to dealer before attempting a fix that does not work in all cases (it does in some).

We have a mystery about why some people never get the leak, some have it fixed with the new breather and some not.
yes its strange if thesame fix is applied to every car
 
yes i went through it (not all but many pages ) not longer you need to do serpentine up and down to stop it .
As you probably know another member @Macadoodle has already tried an extension to the breather with improved results and is now working on another longer extension to my knowledge. Of course a coiled extension/serpentine would probably work but why should we have to modify a brand new car in to this extent when it is up to the makers to sort it out?
I havent heard of owners of other brand EV's or ICE vehicles that have gone to these lengths with a brand new car. They just take them back to the dealer to get sorted.
Also by doing any modification you are running the risk of voiding your warranty even if something happens that is nothing to do with the breather.
 
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As you probably know another member @Macadoodle has already tried an extension to the breather with improved results and is now working on another longer extension to my knowledge. Of course a coiled extension/serpentine would probably work but why should we have to modify a brand new car in to this extent when it is up to the makers to sort it out?
I havent heard of owners of other brand EV's or ICE vehicles that have gone to these lengths with a brand new car. They just take them back to the dealer to get sorted.
Also by doing any modification you are running the risk of voiding your warranty even if something happens that is nothing to do with the breather.
yes you are right but i dont like going around with a problem i know an easy fix to it, if there is another problem i will remove that before i take it in , would be a 5 min job . Its not like im going to open the reduction box and modify that :) (maybe its because i work as a mechanic and i prefer to work on my car and know what im doing than rather give it to someone to experiment with ;) )
 
We believe the problem is the placement of the breather opposite the gear so that oil is flung into it, there is also speculation that foaming is an issue and so oil is travelling up past the breather and escaping.

We do not know for sure. Macadoodle has tried fitting a long pipe but still has leakage.

Yep, 30cm pipe leaked, ran a metre one right up fairly high behind the back bumper, total disaster, leaking all over the inner surface of the bumper and leaking through the joins in the plastic sections of the bumper to the outside, looks terrible !

Soo, I've come to the conclusion that simply extending the pipe with the same ball valve ain't going to work, can't really go much further than behind the rear bumper.
This assembly seems to have the capability of sending its oil far and wide, it's acting like a pump.

Think there's 3 options left inspired by suggestions from forum members --

1.Try without the original breather with its ball valve, its a one way valve after all, and it might be sealing very well and allowing the oil build up. I found a bit of plastic rod that fits the tube end perfectly so I'll drill a 1mm hole in a section of that and push it in the end in place of the breather.

2. Fit a small oil catch bottle, ebay has little aluminium casing fuel filters with 8mm connection stubs which look promising, can take them apart and remove the actual filter and just use the bottle as an in - line catch point.

3. Blank off the current breather position with an M10 bolt stub and washer and move attention to the other side of the box.
Can't remember the size of the filler plug but should be easy enough to make or buy a hollow threaded bolt to fit it as I did with the breather hole.
Its on a horizontal axis in the side of the casing, so not directly above the spinning gears. Also being at the diff end, it's closest to the slowest cog, not above the motor cog.

I think beyond all that..... I GIVE UP :LOL:
 
1.Try without the original breather with its ball valve, its a one way valve after all, and it might be sealing very well and allowing the oil build up. I found a bit of plastic rod that fits the tube end perfectly so I'll drill a 1mm hole in a section of that and push it in the end in place of the breather.

2. Fit a small oil catch bottle, ebay has little aluminium casing fuel filters with 8mm connection stubs which look promising, can take them apart and remove the actual filter and just use the bottle as an in - line catch point.

3. Blank off the current breather position with an M10 bolt stub and washer and move attention to the other side of the box.
Can't remember the size of the filler plug but should be easy enough to make or buy a hollow threaded bolt to fit it as I did with the breather hole.
Its on a horizontal axis in the side of the casing, so not directly above the spinning gears. Also being at the diff end, it's closest to the slowest cog, not above the motor cog.

I think beyond all that..... I GIVE UP :LOL:
Just give it back to the dealer and let them fix it, If they can't then go down the route of getting your money back as the car is not fit for purpose.
 
Yep, 30cm pipe leaked, ran a metre one right up fairly high behind the back bumper, total disaster, leaking all over the inner surface of the bumper and leaking through the joins in the plastic sections of the bumper to the outside, looks terrible !

Soo, I've come to the conclusion that simply extending the pipe with the same ball valve ain't going to work, can't really go much further than behind the rear bumper.
This assembly seems to have the capability of sending its oil far and wide, it's acting like a pump.

Think there's 3 options left inspired by suggestions from forum members --

1.Try without the original breather with its ball valve, its a one way valve after all, and it might be sealing very well and allowing the oil build up. I found a bit of plastic rod that fits the tube end perfectly so I'll drill a 1mm hole in a section of that and push it in the end in place of the breather.

2. Fit a small oil catch bottle, ebay has little aluminium casing fuel filters with 8mm connection stubs which look promising, can take them apart and remove the actual filter and just use the bottle as an in - line catch point.

3. Blank off the current breather position with an M10 bolt stub and washer and move attention to the other side of the box.
Can't remember the size of the filler plug but should be easy enough to make or buy a hollow threaded bolt to fit it as I did with the breather hole.
Its on a horizontal axis in the side of the casing, so not directly above the spinning gears. Also being at the diff end, it's closest to the slowest cog, not above the motor cog.

I think beyond all that..... I GIVE UP :LOL:
i think out of the 3 i would go for the 3rd one , cannot understand how with the long pipe it still came out , normally going up and down with the pipe should stop it , i used it on bad breathers and that stopped it , is it filling up the pipe that much that it fill the long pipe ?
 
Well Ayoull that not I was told on the telephone by thier advisor but I agree this document does say otherwise and I will be calling them again as soon as I can to clarify what was told to me as this is most annoying, I also agree with siteguru above where he as said they found his dealer under Toyota when the adviser looked for my dealer while I was on the phone with him he could not find my dealer under MG but did fine them under Nissan.
Also can I wish you best of luck with the DVSA and this issue.
Les
Hi Les, did you get back in touch with the Ombudsman? Even the MG website says they are a member:
1677674958050.png
 
Yep, 30cm pipe leaked, ran a metre one right up fairly high behind the back bumper, total disaster, leaking all over the inner surface of the bumper and leaking through the joins in the plastic sections of the bumper to the outside, looks terrible !

Soo, I've come to the conclusion that simply extending the pipe with the same ball valve ain't going to work, can't really go much further than behind the rear bumper.
This assembly seems to have the capability of sending its oil far and wide, it's acting like a pump.

Think there's 3 options left inspired by suggestions from forum members --

1.Try without the original breather with its ball valve, its a one way valve after all, and it might be sealing very well and allowing the oil build up. I found a bit of plastic rod that fits the tube end perfectly so I'll drill a 1mm hole in a section of that and push it in the end in place of the breather.

2. Fit a small oil catch bottle, ebay has little aluminium casing fuel filters with 8mm connection stubs which look promising, can take them apart and remove the actual filter and just use the bottle as an in - line catch point.

3. Blank off the current breather position with an M10 bolt stub and washer and move attention to the other side of the box.
Can't remember the size of the filler plug but should be easy enough to make or buy a hollow threaded bolt to fit it as I did with the breather hole.
Its on a horizontal axis in the side of the casing, so not directly above the spinning gears. Also being at the diff end, it's closest to the slowest cog, not above the motor cog.

I think beyond all that..... I GIVE UP :LOL:
The more I read the more I think the problem is the ball valve breather as you say acting as a pump . A gearbox breather should not be one way. I can understand the swan neck pipe, that makes sense , but if you stick a one-way valve on it this just won't work. I have a theory as to why it is not as bad or no leak on some cars fitted with the modified breather. Maybe some cars have a breather without the ball valve , they would look the same on the outside but would operate differently. Just my thoughts.
 
Just give it back to the dealer and let them fix it, If they can't then go down the route of getting your money back as the car is not fit for purpose.
That's not been working, hence some people want to create their own solutions and why shouldn't they if they like the challenge and enjoy experimenting with their cars? No one is saying anyone else has to do the same.

It should be a given that MG should have already fixed this: but they haven't and repeatedly saying they should on this forum isn't taking us anywhere - though DVSA reports are a good way to apply pressure.
 
i think out of the 3 i would go for the 3rd one , cannot understand how with the long pipe it still came out , normally going up and down with the pipe should stop it , i used it on bad breathers and that stopped it , is it filling up the pipe that much that it fill the long pipe ?
Yes, number 3 most likely to work in my view.
 
The reason some cars have it worse than others is merely down to usage.
Many owners just pootle around town at slow speeds with little churning or heat build up. Others drive at higher speeds that causes more heat and expansion. All will leak at some stage.
 
The reason some cars have it worse than others is merely down to usage.
Many owners just pootle around town at slow speeds with little churning or heat build up. Others drive at higher speeds that causes more heat and expansion. All will leak at some stage.
That's speculation. It may well be a factor but we don't know that this explains everything. A lot of cars don't seem to leak at all (the vast majority if you believe MG).

There could be variations of spec of the gearbox or breather, tolerance changes, breather sealing issues, poorly applied fixes AND driving style/usage playing their part.
 

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