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MG MGF Technical - Just discovered HGF

Just had confirmed by the 'very nice man' from the AA that my 2 yr old, 26k mile 1.8i MGF has indeed got HGF. I'm absolutely gutted, the only consillation being that I believe this will be covered by the warranty.

The reason of this post is to try and understand what I do next? I'm leaning towards the line of thinking that once such significant work like this has been done on an engine, it may never be the same again. I will always have in the back of my mind that this may happen again so should I consider selling the car once the 3 yr warranty expires? I'd be interested to hear of other people's experiences.

Also, I'll be asking the dealer:-
1. Why this happened?
2. Is it a regular occurrence?
3. What will they be doing to ensure that it does not happen again?

Is there anything else that I should cover to ensure that the dealer has done a good job?
I notice in the posting "Where does coolant disappear ?" from Oliver G, there is mention of having the coolant expansion tank cap replaced - why is this?

Finally, in case this may help anyone that may come accross a similar problem in the future, here's what happened...

Saturday, ran the car for 5 mins on a fast (60) road, then spent about 10 mins in slow moving traffic. Heard a 'pop' and saw steam comming from the boot lid. Pulled over and when I opened the boot, there had been coolant coming out from underneath the expansion tank cap. The coolant temperature gauge had not gome much over 1/2. When I eventually got the cap off, there was only a small amount of collant left in the expansion tank (it was very hot - just short of boiling). Filled this up at a nearby petrol station (about 1 ltr) and continued the journey, checking the coolant regularly, all was fine.

This morning, all the coolant had gone again, but the car was parked facing downhill, so filled it up again (1 ltr again) and headed home. When I got home, coolant was okay, but I checked the oil to find it was thick and had a small amount of creamy stuff in it - hence alarm bells from what I've read on this BBS. Called AA and they confirmed it.
Duncan

Hard luck Duncan - at least the repair will be covered by warranty.

I'm just thinking out loud here, but I wonder if this was the pattern of events:

1) Coolant cap fails and car looses coolant. Repair cost £3.50
2) Duncan puts nice cold water in his nice hot engine.
3) Significant temperature shock and contraction to engine in the coooling waterways.
4) Head gasket failed as the weakest point. Repair cost £400.

I should point out that on a scale of 100 my technical prowess is much nearer 0 than 100 so the above may be complete nonsense.

Duncans inital symtoms are identical to ones exhibited by my car a few weeks ago on the M25. Fortunatly a fellow TF owner driving in convoy spotted early signs when his car was plastered with coolant and I was able to stop early on. Rather than refill and carry on I got a lift home on the back of a breakdown truck and once I had replaced the cap all was fine.

Anyone care to comment? I wonder on how many head gaskets have failed/been replaced when the original problem/only problem has been the cheap and nasty coolant tank cap.

I am not accusing Duncan of negligance in any way and not all head gasket failures will have occurred in the same fashion - my two to date have been exhibited in different ways, both different to above.

Paul
P9 VLS
Paul

Was your car recently serviced for it's 24000 mile service? If so, was it correctly bled when the coolant was changed?

Coolant header tank caps have been known to give trouble in the past but this was corrected by MGR before you purchased your car, so it is unlikely to have been the cause of your problems. Loss of pressure in the system, when the cap failed, led to localised boiling and hot spots in the cylinder head and differential expansion problems of the head moving versus the block. Consequentialy the head gasket which is in between them, suffers shearing.

Incorrect bleeding of the coolant system can lead to HGFs. If air pockets are left in the cylinder head then this can lead to hot spots with similar consequnces as above.

Journeys which start with fast motoring can also lead to problems. If the car is raced over the first section it will warm up quickly and the thermostat then opens and allows through a large amount of cold water thus cooling the head again. This in turn can lead to differences in temperature between the head and block. The car should be warmed slowly over the first few miles before 'opening her up'. I always allow the oil to reach at least 90 degrees before using full throttle.

On a final note, beware that while your warranty may cover you for catastrophic failure of a component, it may NOT cover you for damage from consequential overheating. So if your head is damaged beyond repair it may not cover the cost of this replacement. I say MAY! It depends upon the warranty. This scenario happened to me. The warrnty company covered the cost of labour and parts to replace the failed head gasket but did not cover the cost of a new head! So lesson to be learnt is; loss of coolant pressure for any reason, stop. Top up when engine has cooled and re bleed if at all possible from all three bleed points if the coolant loss was substantial.

And on that cheery note.....have a good holiday and good luck!

regards

Bruce
Bruce Caldwell

>>>once such significant work like this has been done on an engine, it may never be the same again.
===to set your mind at rest, replacement of a head gasket is a relatively simple and routine job, has been done on all cars since time immemorial, and on the F should improve things not make them worse, particularly if the later gasket and dowels. You just need to ensure whoever does the job is totally familiar with K series cylinder heads and works to high standards. Still a bit of a bu99er when it happens though, you have my sympathy.
David

>>. The coolant temperature gauge had not gome much over 1/2. When I eventually got the cap off, there was only a small amount of collant left in the expansion tank (it was very hot - just short of boiling). Filled this up at a nearby petrol station (about 1 ltr) and continued the journey, checking the coolant regularly, all was fine.<<

Head gaskets on any car often fail as a bi-product result of some previous malfunction or failure. Coolant loss has probably damaged more otherwise sound head gaskets than any other cause. In this instance it appears possible the coolant loss could result in hot spots or more severe engine overheating. This leads to metal distortion with consequential gasket damage......

Simply topping up the coolant is no guarantee that the system on any car has been bled properly. The damage may have already been done. Air pocket hot spots mean this bleeding is critical on cars, particularly those with mid or rear engine locations.

My first MGB had a proper index coolant temperature gauge and it was accurate and reliable. Most cars had one back then. For a number of reasons, mainly to stop panic by some owners, simple idiot lights or not much better 'gauges' with small areas of cold-hot slots either end of a l-o-n-g normal central area are of little help as an indicator of something being wrong. Coolant loss is usually sudden and if not spotted quickly invariably leads to more serious problems ..... on any car.

Anyway, bad luck. Hope it's sorted quickly and you're right to ask .... what was the original cause ... but, this can be a chicken or egg problem even for the more experienced experts.

JMcF.
John McFeely

Oh yes, if they advise that a NEW cylinder head is required and God Forbid, that is not covered, in that position I'd be inclined to get a 2nd opinion. Less expensive options: Repairs are possible to the damaged head or perfectly sound used parts are available. Too many new parts are plonked on modern cars when the old part could still be perfectly serviceable. There are many reasons for this... lazyness, ignorance and yes, larger profits .....

JMcF.
John McFeely

Duncan,

I am really genuinely sorry to hear about your HGF. I have just got mine back from having it fixed. Well I am going back to the garage tomorrow actually as there is oil dripping from the oil sump, and they forgot to give me back my aerial!

Anyway, what I found was that many garages/ dealers won't quote you for the job. they will say that the HG replacement might cost you £500 but they will state that they will not know the true extent of the damage until they have opened it up and had a look. this is a fair point, as there could be untold damage to other components too. I am certainly not an expert on this, but can only tell you what I know from my own experiences. There are some really good MG enthusiasts out there who have alot to say on the subject.

In my case, I had to have another head put on as my was fried and it just seemed like a good idea to go for it. I paid £350 from MG centre (plus Vat and delivery), and Bill is a top bloke, even if you want to chat about it. It was not reconditioned (pay around £650 Ivor Searle to £1500 Brown and Gammons for that). But it had been tested and skimmed, so a much better option for me. There was some pitting on the block which the garage would not deal with, but there are people out there, such as Dave Andrews who can do this kind of job. The dealers are reluctant to apply fixes that have been tried and tested by more adventurous specialists, but you can undertand their view on this.

There is also a load of info about what you should and shouldn't have done in addition to having the gasket replaced. For example, I opted for a Mike Satur competition HG, plus Steel dowels, I had all the belts changed, and had a new water pump (the casue of my HGF was leaky water pump) fitted (watch the price and labour for this job). I also opted for CoolIce, which is a coolant substitute, and is supposed to keep the temperature down by up to 28 degrees. From what I have noticed in the 2 days that I have had the F back is that the temp gauge is 1 notch lower than before, i.e. just under half way. Others might recommend that you make sure the radiator is okay and cooler pipes underneath as these can be troublesome. Yours is a 2 yr old model so maybe not an issue. Some garages have also told me that you cannot just replace the head and not the block, in other words the whole engine, which I don't believe is actually the case. There seem to be enough people who think this is a do-able option, so not sure how true this is.

Now I've got my F back there is the thought in the back of my mind that it could just go again, and the guarantee from the garage is on labour only, and is 3000 miles. After that it is open season! A bit scary and still in 2 minds whether to jump ship and get rid of my F... though I really hate to think about it.

I have plenty of emails from MG owners club, and other people, all of which have something to say on the subject. I will gladly forward these on to you if you so wish?

Anyway, hope things get sorted and that you can be back on the road again soon.

Andy

A P Wrench

Well....
Thanks for your advice everyone, but to cut a long story short, there is no problem - only a faulty coolant filler cap! It took the garage three days to tell me this (and on day two told me they had the head off and it was to go to be skimmed - apparently they got me confused with one of two other MGFs that are in their place at the moment with coolant problems - I dispair). It's been pressure tested without problem.

The reason for the water in the oil? - condensation in the dipstick tube! Apparently this happens on this model due to the unusual oil filler arrangement.

So after being initially p1553d off at the garage for being so disorganised, I was quite relieved to find that the car is fine.

Thanks again for all the advice, and boy am I happy that I didn't need to use it!

Duncan

T9 DAC
Duncan

<<The reason for the water in the oil? - condensation in the dipstick tube! Apparently this happens on this model due to the unusual oil filler arrangement.>>

Never heard any other owner comment on this so keep your eye on the oil and water levels for the next few weeks. If the car is used regularly then you should not be getting condensation in the oil or dipstick tube.

Bruce
Bruce Caldwell

glad to hear it... I wish that had happened to me!
A P Wrench

Durcan
Could i say that may be you should try Honda Next. I run a 18 month old Civic Type R. A real performance car.....its totally MEGA!

14,000 miles..........no problems/no return to the dealership.
QED
Mega
Mega

>> I run a 18 month old Civic Type R. A real performance car..... <<

Getting the top down is a real bast@rd though.
Norman

This thread was discussed between 24/08/2003 and 02/09/2003

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