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MG MGF Technical - HGF

Help, my mgf just had a hgf, luckily i found out about the mayonaise-like substance when i check the oil level before i ran out of radiator coolant. My dealer can only do my car on the 5th of January.

My problem is that my car at the moment is in my garage. Should i start the engine everyday or do i just leave it there & unplug the battery terminals?


I'm sorry about your problem.

> Should i start the engine everyday

>unplug the battery terminals?
No, the battery will remain in good condition until the 5th

I would not ride any more meter to prevent from more damadges. Let it tow in if possible.

Is it a VVC ?

Dieter Koennecke

Thanks Dieter.
Its a 1.8i. Won't the water inside the engine cause any rust? So i'll just have to wait it out till the 5th then.

Cheers & merry christmas.

>Won't the water inside the engine cause any rust?


This water is a mixture of coolant and water. It contends special a rust protection component.

Dieter Koennecke

The less the engine is run the better as until you can confirm the degree of water loss there is a risk of localised overheating which can extend the damage.

You get water in the engine anyway, but only in the cylinders is it not normally present in liquid form. Even there there remains an oil film on the bores and in the honing marks.

Roger Parker

Okay, I'll keep that in mind.
Thanks, Dieter & Roger.

Dear John,

Sorry fo you since I know how you feel.
Mine started to leak this week and hopefully I 'll just have to change the head gasket without any other major repair (1000 just for this over here)( no mayonaise)
In the Uk,
does Rover pay for one part of the repairs since this seems to be a commmon failure. In France they don't seem to be willing to pay that much and I wanted to know if I could benchmark your country while writting to Rover to put some weight in my says.

For the statistics, my HGF blew with 30000 kms and a K&NJ fitted on my 98 Abingdon.


Just picked up my car after a service and new HG.

Car nearly 3 yrs old and 29000 miles.

Rover has picked up 50% of labour cost of HGF repair all though I have picked up most of the parts as I have had fitted, at my request, new belts all round and spark plugs which are not normally due for change until 60,000 miles.

Julian Foulger

As an addendum to my previous comment, in terms of how a customer feels after the event it is not so much the fact the HG fails at a early mileage for a modern car(which is bad enough) but as important is how Rover goes about recompensing the customer like yourself.

My wife's Audi A6 has had its woes but she would buy another Audi because Audi have been very generous in fixing problems at no cost, some of which I would say are as a result of normal wear.

Julian Foulger

Out of morbid curiousity how much does it cost to repair after HGF at the dealer ?


My F blew the head gasket at 27k, 2 days after having the inlet manifold gasket replaced. This involved (supposedly) pressure testing the coolant system and a road test. Clearly my local dealer was told that a £380 bill for a new head gasket was not on.
Replacing HG also involves a new inlet manifold gasket. This, I was told, was a modified part from the original. So if the dealer charges you for a new HG and the new inlet manifold gasket has been fitted, clearly they should not charge for a new one again.
As an aside, all parts were paid for by MG, as car was 2yr 4mnth old at 27353miles. Dealer paid 1/2 labour, (after a threat of taking them to court), and I paid £87.
Cheers Andy C19 MGF
Andy Bourne

Just checking the oil level today I found some mayonaise on the dipstick. Does this definitely mean a HGF? Or could it just be from condensation in the filler neck. There has been no drop in water level in last 6 months, and the engine is running OK. Luckily HGF is covered by my warranty. What else can I check?
Nathan Carnie

Add another HGF to the list!! My VVC blew yesterday. Luckily I was only a short distance from the dealer. At first I thought it was just a loose cap or hose, but their technician had a quick look and diagnosed HGF or water pump failure. Nearly all coolant had puddled underneath whilst I was topping up in a local hostelry. I thought it might have had some thing to do with last service as they had made a point of topping up the coolant. Unfortunately this particular dealer is no longer a Rover franchise (now Honda- I wonder why?) so were not able to give any help ref compensation from Rover although they still do repairs/servicing. Does anyone know who the best person to contact at Rover if this is confirmed as HGF?

145 HGFs now collected through this BBS... keep 'em coming, don't we all love steaming cars!?! ;-)

How many MGFs now produced? 100,000?

Lets keep things in perspective, OK I agree even one HGF is too many, but do remember that those people that have self induced HGFs need you all to complain to make them feel better - and I am not saying that the majority of you have had self-induced HGFs.

BTW I do not think MG Rover are the 'bees knees' or that they are beyond criticism and I do feel and in deed hope that they are going put more effort into quality control of their products and their bought in products and do remmeber that the K Series engine is built by a BMW owned company so is also a bought in component. What make car are you getting next?

Ted Newman

>How many MGFs now produced? 100,000?

67,800 built until now +/- 1000 pcs:)

I've had about 10 or 15 in the german Forum in the last few month, but don't foreward them any more to Dirk.2much flames ;-)
See currently for
'Geruch unter der Haube '
'Problem!! Mein Auto dampft :('

And I'm very sure that its not the built quality but lack of service and stupid workshops !!!

The 'problem!! my car steams' thread relates i.e. to an MGF which had a front accident. After repair of the front ... and cooler... the headgasket blew.

Sorry, but it is as it is.



I found mayonaise on my dipstick and my garage told me it could be due to condensation. Wthin two weeks my Cylinder Head Gasket had blown and my water pump had packed up. If I were you I would have my Gasket replaced A.S.A.P. and the head skimmed before it lets you down miles from home. I was lucky as I was only a couple of miles away.

The only good thing to come out of a Head Gasket blowing is that when the cyclinder head has to be skimmed the engine seems to run a lot better afterwards.


Sorry to hear about your problem!
As far as I know, there are 2 french MGF owners on the BBS (you and me, well at least)

One is suffering HGF and my 1.8mpi had a leak but 'only' the inlet manifold gasket needed to be changed (around 2000FRF including labour) Faulty inlet manifold gasket seems to be a current problem (Rover diagnosed it very quickly) They didn't want to talk to me about HGF ...

Looks like French F's suffer of reliability problems (well OK, they have the same engine) or maintenance and service problems just like their cousins on the other side of the channel!

I hope the MG/Lola car for Le Mans will not blow its engine before the end of the race

I think I probably haven't got a HGF but I'll check the cylinder compression and keep fingers crossed!
Nathan Carnie

My dealer picked up my car on the 4th this month & till now, work is still carried out on it. Dealer do not give warranty if the cylinder head is skimmed but will do it anyway if I allowed them to. Their suggestion was to replace it with a new cylinder head.

The reason I assumed that my car got a HGF is because I found the tell-tale mayo like substance deposited on the dipstick. The engine did not suffer overheating maybe because I found out about it in the early stage of a major HGF.

This being the case, does the head still require skimming? Please help cos I'm planning to visit my dealer tomorrow.

Thanks in advance.

The head only requires skimming if it is distorted and they the dealer or their outside contractor should have the equipment to find out, it would have to be a very serious failure to require a new head!

Ted Newman

If the head had distorted then there is no alternative other than to replace the head, usually the head requires a refacing to remove the liner /gasket indentations around the combustion chambers(4-8 thou"). If the head has overheated severely then it can warp(from front to back) to the extent the valve guides(which are quite short) do not line up with the valve seats resulting in incorrect seating of the valves, no amount of skimming will rectify this. The symtoms are erratic tickover and loss of power.John in your case as Ted suggested a competent machine shop will check the head, have it pressure tested as well.If in doubt ship it up to me and I'll get it done for you.The dealer is covering his ass as he will be able to get a manufacturers warranty on a new part which will cover his labour. If you have the head refaced ,depending on the mileage have the valves recut and new stem seals and cam seals fitted, valve seat angles are important.ALSO find out the cause of the failure!

Thanks Ted/Mike,
I've printed your comments & will let my dealer read it.

Any additional comments are welcome before I go see my dealer tomorrow.

This thread was discussed between 23/12/2000 and 10/01/2001

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