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MG MGF Technical - Overheating and coolant loss at MOT

My car failed its MOT on a number of points, but the most concerning was that it was not possible to complete the emissions test due to 'overheating'.

I went back to the garage to discuss this and it turns that they left the car running during the MOT and coolant started pouring out. It is 30degC here yesterday and it sounds like they left it running for ~45 minutes so it is no big surprise.

Problems are:
- They now want to charge me to 'investigate the fault'
- I am concerned that this will have caused HGF

I have always been extremely careful with coolant levels and coolant loss has been minimal. Last year I replace most cooling system components. I have never had the coolant temperature above 50% of the temperature gauge, or had any temperature warning lights. Therefore it seems a bit of a coincidence that these faults develop as soon as I leave it at the test centre.

I need to go back today and try to find out their version of events and whether they think there is permanent damage. Not convinced I will get a clear answer on either point.

Does anyone have any general advice in this situation?
Is this likely to have caused HGF?

In return I can offer recommendations for MOT test centres in Cambridge area! ;)
Peter

Do you know if the radiator fan (or fans if you have A/C) is/are working? Even if they left it ticking over for an inordinate amount of time, I don't think it should boil over. I've been stuck in traffic with very little airflow over the radiator for significant periods in West Australian temperatures without any overheating problems.

Rgds
Stu
S Craig

Thank you for the quick response!

I forgot to mention the engine-bay cooling fan was definetly working on Sunday. I assume the radiator cooling fans must be working because I am driving in town traffic a lot and the engine temperature has never been above 50% of the marking on the gauge (haha, perhaps I have a dodgy gauge). Oil temperature is never high either.
Peter

Oeer could be HGF...BUT could just be the brown fan sensor in the block malfunctioning.

I've had 2 of these go, but been careful enough to not get an HGF as a result of it. If they have run the engine without coolant in it there could be trouble.

you will know if this sensor has gone as the front/radiator fan won't come on. Not that silly little thing in the engine bay. Also the sensor will tell the engine that it is still cold and will adjust the mixture accordingly, this may be why it failed emmisions.

I think you garage are a bunch of smegheads for letting this happen frankly and you should rebuke them accordingly. No engine needs to run that long for an MOT.

Go through the usual checks to the system for integrity and then for HGF: mayo in Oil, Oil in water. etc. For what it's worth just change the brown water temperature sensor and then bleed and refil coolant PROPERLY. Rob Bell has a site showing you where this is and how to do it.

Then run up the engine to see how it behaves. If you are lucky you may have gotten away with it as I have twice. But then my water didnt come out.

N
Neil

I had my MOT done recently and my car was left to idle for quite a time. However for those of us that live near the M25 this wouldn't be unusual ! The car should be able to sit for a long period of time at idle with the fan cutting in and out without any problems. As for a cause, the fan not working or possibly a defective pressure cap ?
Stuart

Unfortunately I think there is not much I can do about them except be polite and civil.

The MOT has not expired and so they will not let me drive the car away (they could in theory call the police if I do). I do not have the facilities to move it myself.

Meanwhile I am paying serious cash for things I have not even asked them to do.

Do you have to drain the coolant to change the temperature sensor? They have already bled and refilled once.
Peter

>> The MOT has not expired and so they will not let me drive the car away <<

I am sure that you are permitted to drive the car to a place where rectification work can be undertaken?

Might be worth checking out the DVLA website for clarification. You are certainly permitted to drive the car to an MoT station to get the car tested, so you could argue that you are taking the car to another place for a second opinion! ;o)
Rob Bell

I think you can't drive the car once the MOT has expired, or if the MOT tester actually signs a 'Fail' certificate.

Anyway, they did some pressure checks yesterday and apparently the cylinder head gasket has failed. There was no sign of any problems until they carried out the MOT test - but maybe it was on its way out.

"Carried out engine cylinder leakage, found pressure pushing coolant out of header tank from number 2 cylinder. Suspect headgasket failure, requires cylinder head removal for further investigation."

Now I find that I am 1800 miles over by 12k service and so the warranty company will no honour the warranty.

My best guess is that I will leave the vehicle at the main dealer to get all the work done. It will be expensive but I don't know any other options in the area....unless someone can recomend. Presumably they will be able to fix it OK?

Any other ideas?

The car needs new front tyres, wishbones, discs and pads - so maybe I should try to sell it for scrap? It is N-plate, 90k...

Maybe the head gasket isn't too bad and I can continue to run it?
P J Stubberfield

Basically there are two options.

First is to leave it with the MoT people for them to investigate and replace the gasket.

Second is to arrange transport for the car to another garage for investigation and repair.

The first option is clearly the easiest and most convenient. Possibly the most expensive - it may be worth your while asking them to quote for the work and indicate that you're considering having the work carried out by a third party.

The second option is rather more involved. You need to find a specialist who can do the work for you, and arrange for either them to collect the car, or arrange transport (additional cost I am afraid).

Given your location, you could try Brown and Gammons or Techspeed. The latter would be my choice based on personal experience (I've not actually used B&G for service/repair work). Techspeed could also collect the car - however, they're right in the middle of the racing season with the BTCC - so may not be in a position to help... Try phoning both - a simple head gasket repair ought to be reasonably affordable - 3-400 quid. Ish. Other repairs extra.

If you want to sell the car for scrap, then I am sure I could find it a good home (but don't tell Yimmy - she'll kill me!)
Rob Bell

I think you are right, I don't want to sell it for scrap. I have just been looking at 230002763537 on ebay. It looks great until you get round to the contents of the boot.

I will leave it at the main dealer and get them to take the head off and see what the damage is. I don't think it can be too bad because it hasn't been overheating or losing coolant until they get hold of it.

I am sure B&G or Techspeed would be good, but the main dealer should be able to do it, without involving cost of transport. They had 4 MGFs in there today so they must have some experience with them.

Any ideas how many hours for head off, new gasket and head back on again?
P J Stubberfield

This thread was discussed between 05/07/2006 and 06/07/2006

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