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MG MGF Technical - HGF Maybe?

Hi all.
Just been looking at the recent threads and am a little concerned with my F. Noticed the other day the coolant was low, so topped up last night. I've done around 50 miles today and checked the level again and it has lowered to about half way. You guys have all got me worried about this HGF and would appreciate any advice on my next step. Can't see any coolant on the floor but not really very good with mechanical stuff. The car is a 1997 and done 55000 miles
Please help
Ian

Don't panic yet Ian; what you clearly don't have a catastrophic HGF - yet.

In fact, you may not have a HGF at all.

First things to check are the condition of the coolant and the engine oil.

The coolant should have no signs of an oil film whatsoever. It should be green (unless OAT fluid has been used in the past - in which case it'll be orange!) - with no contamination.

The engine oil (check the dip stick) should be brown (sometimes black) - if you have a HGF, and coolant has entered the engine, the oil goes a creamy colour - with the consistency of mayonnaise (hence often referred to as 'mayo').

If these checks prove to be okay - then the chances of a HGF are much less, but not erradicated.

The next step is to check the coolant for HC (Hydrocarbon) contamination - there should be NO HCs in the coolant, as they are products of combustaion! Get an MoT exhaust gas analyser to 'sniff' the expansion tank.

Next step is to closely monitor the coolant levels. It may be that you have a pressure or coolant leak.

Actions:
1. replace the expansion tank cap - they're cheap either from MGR or Halfords.
2. If this does not help, suspect the radiator/ coolant pipes/ joints/ etc - seek professional advice: Try Techspeed/ Mike Satur/ Brown and Gammons - who ever is the closest to you.

More on HGF at http://www.mgf.ultimatemg.com/hgf_pages/HGF.htm

Hope this helps!
Rob Bell

Thanks Rob

Checked the oil and coolant yesterday and there doesn't seem to be any mayo. What is OAT, i replaced some of the coolant with 50-50 water and orange coolant, but the coolant was green before? i checked in the manual and it said it was the correct stuff.
have i made it worse?
Any good garages in the north of england, nr middlesbrough? anyone?
Ian

Fingers crossed for you Ian, what i did yesterday was join the AA, after seeing some of the comments on gen thread, "Today i would like to thank" Rob of Sheffield made me think, so i rang AA, have a read of my comment it's at end of thread at mo, might be worth you considering to have peace of mind as it were' Dave.
DC Morris

>The car is a 1997 and done 55000 miles

VVC ?
Or MPI ?
Mind you on the change of the inlet manifold gasket at MPI if not already done.
Dieter K.

It's the 1.8i,
just joined the AA, but car is due in the garage on monday to fix the reverse gear prob, i've only had the car 4 months. What should i get the garage to do to check for the coolant leak probs. The garage is a MG Rover reg vardy
Ian

The may be can check the repair history due to the inlet manifold gasket change. (Not sure)

In any way the coulour of the newer gasket can be checked at one location on the left of the plastic manifold flange. there is a small gap were the gasket is visible.
Looking downward to the engine bay from the fuel filler cap side. Airfilter hose removed. I remember I spotted a green stain there.
If nothing green appears it might be the old black rubber, prone to leak.

A pressure test to the coolant system will show last evidence whether there is a leak and probably where it is.

Back to normal. Keep cool, may be only the cap is broken and you got nicked by raising/lowering coolant due to temperature and pressure differences.

I'd put the car on plain level. Cold engine. Open the cap and check coolant level. Re-fill with water to the higher level of the mark inside the coolant expansion tank (same height is the level of the outer tank weld seam).
Put the cap back and drive the engine warm. Stop with the car on the same plain level and look for the current coolant height under hot conditions.
If it has raised dramatic by 2 or more inches then the cap is broken.
Hope this makes sense :)

HTH
Dieter
Dieter K.

Remember AA's warranty has to be in force for 14 days before failure for them to pay out (I believe, should say this in terms and conditions).

Leigh
Leigh Reid

Correct Leigh, Dave.
DC Morris

Ian,

I've just experienced similar symptoms to yourself. Water loss but no sign of water under the car ie drips on the ground. Found out that it was the top engine hose split slightly and water only sprayed out when the engine was hot and the pressure high. Check out the hoses, radiator and pipes under the car first.

Bruce
Bruce Caldwell

>>The may be can check the repair history due to the inlet manifold gasket change. (Not sure)
In any way the coulour of the newer gasket can be checked at one location on the left of the plastic manifold flange. there is a small gap were the gasket is visible.<<

Pictured here: http://www.mgf.ultimatemg.com/hgf_pages/HGF_images/green_IMG.JPG

I agree with Dieter.

First thing is to replace the expansion cap.
Then you have to monitor the coolant levels in a methodical manner over a period of days/weeks.

If there is fluid loss, then the inlet manifold, radiator, coolant pipes and flexible rubber hoses all become suspects.

Regarding the antifreeze - hey, I noticed that the Unipart Super Freeze 3 (or what ever its called) is now orange. I was going to top it up in my car too - but stopped when I spotted it was orange as opposed to the expected green.

Very very odd. Anyone had experience with this?
Rob Bell

>>What is OAT?<<

Organic Acid Treatment I believe. Introduced a few years ago as a more environmentally friendly replacement for the nasty old stuff.

Given the age and mileage of your car I guess your due for the 5 year service soon anyway? If this is the case then it's the best time (there's never a good time, but I'm sure you get my drift) for HGF to occur. By combining the 5 year service and HG replacement then you won't be paying loads more than for the 5 year service itself.

If it does turn out to be HGF then check things like the condition of the coolant pipes and radiator, which can become quite corroded at around 5 years of age. These could be the source of coolant loss.

Anyway, keeping fingers crossed that a pressure test will show it's something easily fixed.

Jim
Jim Hosking

Thanks for all the responses. The car is now in the garage and i'm getting them to do a pressure test. Don't think the garage really know what they are doing anyway, don't seem too switched on. Bought the car at the start of january and this is the 3rd time it has been in. This time it's going in for the reverse gear problem and i've got 205 on all four wheels. i only noticed when i came to check the tyre pressure. The garage more or less acused me of changing the front ones even though they are half worn
Ian

> has lowered to about half way

Just to point out, the seam running 1/2 way down the tank is IIRC the max level it should be at. Above this and you may lose some coolant out the cap when expansion occurs when the engine is hot.

As car as a '97, and has a fair old mileage, might be something as innocuous as coolant pipes or radiator.

Leigh
Leigh Reid

Just got back from the garage and they reckon it is the head gasket and the radiator. Both need replacing and they have quoted me £430.
As I have only had the car just over 3 months I wanted it done under the warranty, unlucky, it just ran out 14 days previously and i didn't take out an extended warranty when I bought the car. However, I booked the car in on March 30th making it still in warranty but had to wait for 15 days for a curtosy (bad spelling) car. Argued this and they agreed to let me take out a 1 year warranty at cost price of £240. So I get the car fixed and a 1 year warranty. Phew. Don't expect this to be the last of my problems tho.
Does anyone know of any good garages in the north of England? Pref in County Durham.
Ian

Might try to get them to change the cam belt while they are taking the engine apart for a reduced price, do you think they will go for it?
Ian

£430 for replacement of Rad and HG is a good price though. Normally looking at £500 - £600 for HG alone.
Leigh Reid

Another one bites the dust!
It may not be a HGF.......but its not looking good;)

i am sorry, i am in a nasty mood tonight.
Mega
Mega

This thread was discussed between 10/04/2003 and 18/04/2003

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