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MG MGF Technical - Possible HGF? Ideas needed!

A month ago I had a lot of steam coming out of the engine when I parked up, and once it had stopped I looked and there was no coolant left in reservoir.

Took to a garage, told them this, he checked it over and said there was no problem and to just keep an eye on it. He said he'd pressure tested the engine and it was fine. No contamination visible in oil or coolant either.

A week leter the coolant is still going down, so took it back, and he said it now needs head gasket replacing. Still no oil or coolant contamination.

Took it to a mechanic mate who ran some sort of chemical test on the coolant, with some blue dye, and it didn't react/stayed blue, so he said he doubted it needed head gasket replacing.

Have now noticed a pool of coolant under the car this morning.

Any ideas as to what is happening?! I don't know what/who to believe!

Many thanks
Caroline
Caroline

Caroline,
If the oil and water are not mixing and there is no reaction when carrying out the block test then the pool of coolant under the vehicle is now the place to start investigating. It could be anything from the pressure cap failing to the head gasket failing and causing coolant to leak down the side of the block.
If the leak is now visibly apparent then it's worth carrying out another pressure test.
If you're told it's HGF but you are not shown the evidence then get a second opinion.
Steve T

Hi Caroline,

If the coolant got that low it could have left an airlock in the cooling system, so have it bled thoroughly. As Steve says, it could be as simple as the expansion tank cap having failed. It's generally worth replacing that just as a precaution, and then getting another pressure test done.

Has the temperature gauge ever shown anything other than 'normal'?
Mike Hankin

Mike,

Thanks for the comments.

I've just bought a new expansion tank cap so will fit
that tonight and see what happens.

Temperature gauge has been completely normal, and I don't think I remember it raising when the initial lot of steam came out either.

Will take to another garage for a second opinion too.

Thanks,
Caroline
Caroline

Caroline, what age/model is your MG?
Rob Bell

It's a W-Reg, first registered in 2000.
It's just a 'normal' one, not VVC.
Caroline
Caroline

A loss of coolant can have many sources - the expansion cap being one candidate that is worth addressing (as it is cheap and easy to replace).

The other area that coolant can leak from is the inlet manifold gasket. Yours is a relatively late MGF, and should benefit from the latest (green coloured) gasket seal - but this is another area that is worth closer attention.

Other areas of coolant leaks on older vehicles are the under-body coolant pipes and the radiator. If these are leaking, it should have been picked up on a pressure test, but these are such common causes of coolant leaks they are worth close inspection and replacement if necessary.

Keep us posted Caroline
Rob Bell

Well...

I put the new cap on last night, topped up the coolant and drove it 10 miles this morning.

Having pulled up there was the dreaded steam visibly coming out of the boot/engine area.

Looking closer the steam wasn't coming out of the expansion tank, but somewhere in the boot just above the rear lights - looked like some sort of vent above the lights?

Any ideas? Or have I just got to get it to a garage pretty soon?!

Thanks
Caroline
Caroline

Recommend you get to a trustworthy garage, sorry Caroline

Neil

Hi,

The coolant is definitely leaking, I can see it dripping underneath the car, so I called the RAC out to it (why I didn't think of this earlier I don't know!).

He said he's virtually certain it's not the head gasket and that it's a problem with the water pump instead.

Does this sound realistic?

Taking it to a garage on Monday afternoon, but thought I'd put the note here to see if this sounded a likely cause of the problem.

Thanks
Caroline
Caroline

Caroline
From discussions I've had with RAC mech's following 2 blown hoses and a puncture in the F, they seem to be fed up with attending to K series HGFs. If he says it's prob not HGF I'd take his word for it.
If you're getting a new water pump fitted ask them to change the cam belt at the same time, and to make a note of it in your service book, listing the mileage. It's really due anyway at 5+ years old. Oh! and get the coolant system flushed and refilled while they're at it.
HTH
Gareth
g hampson

This thread was discussed between 21/02/2006 and 26/02/2006

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