MG4 Reduction Gearbox Oil Leak

Looking at exploded diagrams of the motor / gear assembly it would seem that it's a 'wet motor' the paltry 0.9 litres of oil has a lot to do. Flows over and cools the stator windings, lubes the motor bearings as well as the gear teeth and bearings.
I would be slightly worried about the assembly losing more than a small amount, could set up some future issues.
Hope the warranty is going to be honoured regardless of cost to SIAC .
 
Miles Roberts CG said:
I have had an email from MG to say they have identified the fix and will be communicating it to the dealer network tomorrow.
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Thanks for keeping us updated @Miles Roberts CG .
Do you know if this fix will be applied only to cars returned to dealers with leak issues or will it also be proactively applied to new cars during PDI before releasing to customers ?
 
92F01BBF-3242-4DC4-B8D6-E22016F90193.jpeg
dropped the car off the 70 miles to my supplying dealer on Saturday to get the oil leak fixed and got an ICE loaner. Received a phone call today to say it was fixed… went all the way up there, picked the car up and drove back. Picture is from the back of the car when I got home… chalk another one that wasn’t fixed by draining and refilling 🙄🙄🙄
 
PhilYerBoots said:
Thanks for keeping us updated @Miles Roberts CG .
Do you know if this fix will be applied only to cars returned to dealers with leak issues or will it also be proactively applied to new cars during PDI before releasing to customers ?
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I would hope whatever the fix is will be applied to every MG4 no matter if there is a leak or not at this moment in time because if something has been found to be wrong with a component or in the manufacture of this vehicle it will probably become a problem at some point in its life in the future.
Les
 
Yeah me too Les, which is why I asked the question.
We're still waiting to collect our MG4, soon hopefully, and I'd rather not have to do a long drive back to dealers with a leaky car.
 
PhilYerBoots said:
Yeah me too Les, which is why I asked the question.
We're still waiting to collect our MG4, soon hopefully, and I'd rather not have to do a long drive back to dealers with a leaky car.
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Agreed mate, I do hope you are not like me, and do not have to.

That all being said…….you are gonna love this car!!
 
Harry 17 said:
Agreed mate, I do hope you are not like me, and do not have to.

That all being said…….you are gonna love this car!!
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That bottom line is very true Harry17 my misses does as well went out in it this afternoon first time on her own came back 2/3 hours later big grin on her face and saying I’ve been here been there and I’ve been everywhere brilliant no problem at all and I love not having to rummage about in my hand bag looking for my keys to open the boot and the doors fantastic.
Les
P.s think perhaps she may have forgot about the sill issue. Sssssh.
 
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Macadoodle said:
Looking at exploded diagrams of the motor / gear assembly it would seem that it's a 'wet motor' the paltry 0.9 litres of oil has a lot to do. Flows over and cools the stator windings, lubes the motor bearings as well as the gear teeth and bearings.
I would be slightly worried about the assembly losing more than a small amount, could set up some future issues.
Hope the warranty is going to be honoured regardless of cost to SIAC .
Click to expand...
I have never seen an electric motor cooled by oil? There has to be an air gap between Stator and Rotor as would be too much friction and hence heat would be quite explosive I would say. Oil will only be for the gears and end bearing. I would think there will be an oil seal between the end casings and stator casing.
 
Hallix73 said:
I have never seen an electric motor cooled by oil? There has to be an air gap between Stator and Rotor as would be too much friction and hence heat would be quite explosive I would say. Oil will only be for the gears and end bearing. I would think there will be an oil seal between the end casings and stator casing.
Click to expand...
Well, for maximum efficiency, the gap between rotor and stator needs to be small, and this would seem to rule out any presence of oil - though the end-bearing would need to be lubricated. However, the diagram sort of implies that there isn't any partitioning between motor and gears, so it's all a bit confusing.

By the way, motor and related electronics are water/glycol cooled, so presumably the casing has cooling channels to support this...
 
Miles Roberts CG said:
I have had an email from MG to say they have identified the fix and will be communicating it to the dealer network tomorrow.
Click to expand...
Good news. Not sure why they need to wait another day before communicating with dealers though.

Is the fix a secret, or are we allowed to know? Will it require new parts to be manufactured and distributed?

What will it mean to current owners? I guess cars will need to be booked in to the dealer network for a period to apply the fix. Will it be 'while you wait', same day, or longer? Can owners continue to drive their cars in the meantime?

Will fix need to be applied before new cars are handed over? Will this result in a delay before owners might get their new cars? If so how long might this delay be bearing in mind a potential backlog of work fixing cars that are already on the road?
 
Fogey said:
Well, for maximum efficiency, the gap between rotor and stator needs to be small, and this would seem to rule out any presence of oil - though the end-bearing would need to be lubricated. However, the diagram sort of implies that there isn't any partitioning between motor and gears, so it's all a bit confusing.

By the way, motor and related electronics are water/glycol cooled, so presumably the casing has cooling channels to support this...
Click to expand...
I agree the casing will have cooling channels. The diagram is hard to see a divisional wall byr must have really.
 
My MG4 Trophy was supposed to be delivered to the dealership last week, but has not turned up there yet. Hopefully this is because MG UK are implementing "the fix" to all remaining cars in their hands from the first batch, before releasing them to the dealers. Shame my "old" car (a 5 month old ZS EV) was collected yesterday by the dealer I found through Motorway.co.uk...

I'm still very positive and optimistic about MG4 ownership. Based on my test drive, it is a significant leap forward in sophistication, in terms of ride and technology, from my previous ZS EV. I'm still keen to see the announcement from MG about the nature of the problem the team in China have identified and the measures they are taking to resolve it.
 
Hallix73 said:
I have never seen an electric motor cooled by oil? There has to be an air gap between Stator and Rotor as would be too much friction and hence heat would be quite explosive I would say. Oil will only be for the gears and end bearing. I would think there will be an oil seal between the end casings and stator casing.
Click to expand...
Toyota Prius electric motors run in oil.
 
Hallix73 said:
I have never seen an electric motor cooled by oil?
Click to expand...
If you skip to 27.40 he talks about the oil flowing over the stator windings, its a mach e motor so a wee bit more spicy than the MG4 it must be said.
I do find the concept weird too, how do you stop the oil getting on the rotor and creating unwelcome drag ?
Oil wont bother windings though, many high voltage transformers live in an oil bath.
 

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