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MG MGF Technical - Blown Head gasket

I have just had my MGF VVC towed by the AA to the dealer I bought it from 5 months ago. When I bought it
it had 22k on the clock(1997) and at 27k it has now
blown the head gasket, its sluggish starting and the windows don't align anymore, letting water in.

A few questions to the more experienced people out there: How long does it take to replace a head gasket?
the garage is telling me it will not be ready for over a week, How will I know if the engine has to be changed,? I believe a head gasket failure can wreck an engine, if the hgf has done some damage, can they get away without replacing the engine and leaving me with a lemon. What's the best way to approach this with them..?
By the way it is covered by warranty, when the work is done should I approach them to get the warranty increased by 5 months as a freebie.? As for the window alignment problem is this easy to rectify ? and any comments on the sluggish first start would be appreciated. I know its a lot of questions but I would be grateful of some input from any experienced MGF'rs.




The bad news is that headgasket failures are too common on Fs. The good news is that the only thing that usually needs to be replaced is the head gasket. Lots of people on this board have reported the problem but VERY few have mentioned any other engine damager either at the time or afterwards. Assuming you stopped when you saw the steam and/or saw the temperature rise, you should be safe.

The F is fitted with long live spark plugs that should be changed at 50k or 60k miles. However they actually deteriorate faster than this and changing them costs little and should have a dramatic effect. Also the HT leads loose quality with age and changing these will also make a noticable improvement. Both are easy to do your self and also pretty cheap for the garage to do as part of the headgasket job. Change the plugs and leads should fix your starting problems.

If your windows are leaking this could either be due to a misalignment that a competent MG garage should be able to fix easily. The other possiblity is the the window stops have broken. The new stops are a few pounds but fitting them means removing the inner door panels.

Suggest you get the garage to fix the head and windows under warranty and offer to pay for new plugs and HT leads. The Brown and Gammon silicone ones are great.

Hope this help and that you F starts to deliver you some trouble free fun.




Hi Bryan

Sorry to hear about your HGF.

I had one a year ago and all they replaced was the gasket. I'd say the engine runns better now than before, so I wouldn't worry about damage to the engine unless you ran the car with no water in it for any length of time.

Stefan Gibney

Re the spark plugs, I now have more than 75000km on the clock of my 1997 mpi.
When should I change them? Any 'exterior signs' which could show it's time to replace them?



as soon as possible! You WILL notice a difference, especially if you do the leads as well. Next time you have the engine cover off, I'd suggest

Ed Clarke


Dont want to scare you but out of 70,000 *F*s produced about 75,000 have had head gaskets go and what the others have not told you is that the head gasket failure (HGF) also causes the front tracking to go out of true, the footwell to leak on the passenger side and it also causes the driver to have to wear his baseball hat the wrong way round.

In case you do not think I am being 100% truthful try searching the archives for anything related to Luxembourg - where you will no doubt find that I am at least 10,000 HGFs out of date.

N11KRT The Green Squirrel - still trying to find his nuts.
Ted Newman


For best possible performance change your plugs at least once a year. If you do this don't bother paying the xtra for the platinum ones. Use the standard double copper types. You might want to change HT leads every 3-4 years depending on use.

I just changed mine. In the process I snapped off the top of one of the HT leads so I'm about to fit the magnecor Performance leads (B+G @ 60GBP a set). I had no intention of buying these (OEM ones performed OK as they had been changed about 18 mths ago) but looking at the construction of the OEM ones I thought it better to shell out the xtra now.


Aaaaaaaaaaaand another one bites the dust!


first of all, the reason this HGF happens is very simple: PILOT ERROR. So buy a Fiesta instead, you can trash that one without breaking it. MGFs & HGFs have a very complicated relationship. Some on this BBS (esp. those who eat nuts) tend to say it's a very normal thing, because they never experienced it. Then there are others who had 1 or more HGFs (around 100) and cannot be convinced of the F's innocence despite eating nuts etc. And then there's the majority who didn't suffer a HGF yet due to lack of mileage, age or unluck.

How long does it take: 1 DAY, MAX 2 if they want to recheck all the rest (incl. bleeding, other gaskets, liners, screws, connectors) very very thoroughly.

Check pix on my website to have an idea what is done at dealer when a HGF occurs.

The head of the engine is taken off, rest of engine stays inside car. some standard things are replaced, even if they are still ok and hopla, back together following a strict scheme to avoid any assembly blunders. 500 is going-rate, all in. Parts price is only 20 or so, rest is labour.

Engine should only be replaced if you didn't notice you HGF and drove along for a long time without coolant, causing really overheating engine parts, which damage cylinder heads, valves etc.
If the gasket fails towards inside of engine (with MGF it's almost always towards outside - cf. pissing car instead of white smoke out of tailpipes) there can be more risk of engine damage, but quite honestly such cases are verrrrrrrrrrrry rare.

Normally you got a guarantee on the works done, so if something screws up (due to bad bleeding, unseen engine damage etc) don't worry, Rover will most of the time pay all additional costs caused by dealer blunders.

>As for the window alignment problem is this easy to rectify?

30mins max

>and any comments on the sluggish first start would be appreciated.

holy, hot topic lately: plugs, leads, pump, ECU, battery, sensors... can be 10.000 things! Like Pat said, plugs & HT leads are 90% of origin of problem.

Can I have your car details so I can give you free membership for the Hall Of Shame 'No-Nuts' Club.

and Ted, shut up.

Looks like everyone else has answered your questions Bryan apart from how long it takes to replace the head gasket. Same thing happened to me at 24k the day before Christmas Eve and 300 miles from home! The local dealer (C.D. Brammel of Newcastle-under-Lyme) ordered, received and fitted a new engine block in 24 hours...not bad eh!

My advise is kick up a stink and demand that it's attended to ASAP 'cause it should never have happened in the first place. My moaning also got me 500 quids worth of accessories (albeit 6 months later).

Good Luck!

Simon, can I have your details, also you are entitled a free Hall of Shame membership.

Did they replace the engine block for a head gasket???? I think you are mistaken here, in 24hrs they can't order, deliver & replace your engine, knowing only 8hrs a day they work. (I had my engine also replaced, took already 2 days to deliver it, about 3 days to fit it and making sure the new engine was really well fitted & reconnected (clutch, sensors, basically everything!) With you they just replaced the tiny 15 head gasket, not such a big deal.

>and Ted, shut up.<

Sorry Sir Dirk of Luxembourg - I keep forgetting only Dirk is allowed to spout bullsh*t!

Ted Newman

I bought a '96 F a couple of days before Christmas. The head gasket had blown and the owner had apparently driven with the gasket leaking for a while because there was about one litre of oil in the cooling system and also water in the oil. The gasket had failed around the oil pressure channel leading to the camshaft bearings.

Now I've just finished the repair job. Two garages independently estimated the job to take approx. 16 hours which would cost the equal of 1.200 in Norwegian money. I've been taking it easy, working an hour or two a day and also been waiting for parts to arrive from England. Maybe the entire job has taken me twenty hours to complete, including smoking and chatting with visiting mates. Now when I know how to do it I think I could do it in a day if I had to.

Being a member of the MG Owners' Club, I have received excellent service by e-mail whenever anything has been unclear to me. Parts, including a competition head gasket and reinforced timing belt, were sourced from Mike Satur. He also recommended the bolts/studs/nuts fixing the inlet manifold to the head to be replaced by studs and locking nuts.

I started the engine today. It runs sweetly, but there is still a lot of oil left in the cooling system. Seems like I'll have to flush it thorougly before I fill it with antifreeze. If I take it outdoor I will definitely need that (the antifreeze) because right now the temperature is 19 degrees below!

My car has 66.000km on the clock. Seems that most HGF occur around that kilometerage. What causes the HGF's will probably be discussed on these threads for ages still, but my theory is that the secret lies in the construction of the engine. Steel and light alloy expand at highly different rates which forces the material in the gasket to go tired with age. The sealing strips finally loses adhesion to the shiny gasket frame when it has been heated and cooled for a sufficient number of times. Overheating (and perhaps cooling) does not make life easier for it. Therefore, I think that sooner or later ALL MGF's will suffer an HGF. Pessimistic? For all those who have not had a head gasket failure yet I hope I'm wrong. Is there anybody out there having clocked say 10.000 miles yet without blowing an HG?

Hopefully, I will not experience another HGF myself as I do not intend to keep the car for more than a year or two. The critical phase is now during the first days after assembly I think, getting the air out of the cooling system securing the coolant circulation to avoid overheating. I found what I think is a smart way to pressure bleed the system: I disconnected the bleeding hose from the the cylinder head to the expansion tank. By applying compressed air to the free end of the hose, coolant could be pressure bled through the bleeding points.

Having a workshop manual is essential to carry out an HGF repair. Among other things it is important not to turn the crank with the head removed as the "damp" cylinder liners could work loose.

With the engine sorted I now face replacing both window stoppers which hopefully will cure the water leak that had soaked the carpets. Then I can start looking forward to the long Scandinavian summer days cruising in my red MGF.

Jon A. Fredheim


Thanks for a very constructive posting, well done and good luck!

Ted Newman

This thread was discussed between 31/01/2001 and 05/02/2001

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