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MG MGF Technical - empty coolant tank!

Hi! all. Thanks for your tips on the handbrake indicator. Will look into that sometime. More important problem ATM. After having new stainless steel coolant pipework last month i ended up with an empty coolant tank on my way home from London Wednesday. Knew there was a problem when the fans went on even once I'd turned the heating on full to keep car engine as cool as poss. Called AA out. They said water pump leak; that would be my suggestion, too, even being a woman! They filled up the tank and added the rad-seal stuff which immediately stopped the leak, bar the odd dribble overnight in my garage (that might just be remnants from original leak on the underside of the car, especially as it was red coloured, and no antifreeze was added by the AA, though there is the rad-seal stuff).

I take the car to another garage 2day. They tell me there is no leak but there was an airlock which would be the cause.. Now, as I say I'm only a woman, but, surely water would only gush out from a leaking pump or seal or gaiter when the engine is switched off? It leaked faster when the engine was on. How would all the water come out the tank in a 45 minute drive if there was only an airlock?

What should i do, apart from scream or drive the car into a brick wall? Should i get them to just change the pump? If it is not leaking anymore shall I assume that all is OK now and i can carry on driving? Or is it a miracle from God and i should become a nun?

answers as soon as poss. please as these guys still have my car in their garage!

many thanx as always xx

if you have an airlock then the coolant can boil and throw coolant out of the coolant cap (it vents if the pressure gets too high).

see if you can have a look where the leak is. The waterpump will leak out of the cam belt cover, head gasket often out over the alternator, loose pipework is mostly central
Will Munns

Thanks Will;

The coolant cap is plastic (I didn't realise it would let water out if it gets too hot; but there is no scaling or anything around the bottle). Also the leak appears to be exactly under the coolant tank. As soon as i was putting water in it just came out again!

The old garage did put on a new cambelt a few months ago.

ta, janine

Can you see the water comming thru with a torch?

Sadly the cambelt is in front of the coolant tank and the alternator in front of that, so looking at the floor isn't that much help.
Will Munns

fuel pumpe charge

No to the convent, and no to the brick wall. Could be a split hose/poor connection on the expansion bottle? If so the airlock theory could still be partly right. But it doesn't sound like it came about without warning; so....
When did you last check the the level in the expansion bottle? A truthful but wrong answer could reopen the convent option.


I didn't become a nun! BTW I check the water levels almost daily. On Saturday the garage phoned me up to say that after pressure testing they found the leak in the water pump which is exactly what i thought in the first place, so they put in a new one and changed a belt, too (not the cambelt - that is new and was fitted last service I had). They also removed the rad-seal, that the AA had put in, to my relief as I don't like the idea of that stuff inside the pipework.

Seems to be fine now, but although water temp is below 1/2 way (~40%), but oil level is slightly higher at around 120 degrees. Is that too high?

Finally, the coolant i have is blue and the one in the water tank is pink. I forget which was the better one and whether you can mix the two. Answers would be gratefully received!

xx janine

I see no-one has answered you Janine. I no longer have an MGF (I'm happy to say) but can tell you this. The water temp on mine was always just below 1/2 and I think that is the usual reading for these cars. The oil temp should be above 90 degrees and 120 isn't too much. The gauge is probably not too accurate anyway. The original cars had blue/green antifreeze and the later ones pink (OAT) coolant. The two types SHOULD NOT be mixed.
Mike Howlett

Thanks Mike!

I agree about the water temp - just under half way is right, but i'd be concerned about the oil temp - would only expect to see this figure after a long very hard run.
CW Faux

This thread was discussed between 10/10/2008 and 27/10/2008

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