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MG MGF Technical - Urgent Help Required regarding coolant

My 1.8F has recently developed a coolant leak from one of the pipes on the cyclinder head. The last journey I made in the car was approximately 120 miles. The coolant level was at the maximum when I set off.

I have just checked the coolant level before setting off home for Christmas and it took the best part of 1.5l of coolant to top it back up.

It only leaks when the engine is running i.e when the system is pressurised.

My question is : is there now a risk that some air may have got into the system and it will require bleeding or am I safe to head off?

(As it swallowed the coolant it did make one or two gargling sounds as if air was escaping back through the expansion tank).
R Longmore

Bad news just before xams.

1.5 litres seems a major amount to have to top up. I think I would personally have the car bled correctly not just hope a top up will have forced out any air. Too many problems can/may occur if any air is in the system - namely the dreaded HGF.

Im sure you will get more advice but I would not run the car myself too far with out having it checked out correctly once you have fixed the leak. Not worth the risk of damaging the engine etc if you create a hot spot. Gets even more expensive if that occurs.

Keith
Keith Williams

If the expansion bottle emptied and your description sounds like it did, then certianly bleed the system before you drive it. Instructions on Rob Bell's site here

http://www.mgf.ultimatemg.com/hgf_pages/coolant_bleed_procedure.htm

Dave Livingstone

Thanks for you help gents.

Yes the expansion tank certainly did empty and more because it took a while before it started to fill up.

Just to add insult to injury the battery has also given up the ghost as well. Chrichy its only been stood a week!

My plan is to drive it about 1 mile (once i've scrounged a jump start off someone) to a garage where I can work on it out of this terrible weather an poor light. Hopefully no damage will be done in that short period of time, but I can't work on it where it stands. Maybe getting it towed there is a better idea?

The instructions are very good and im confident I will be able to bleed the system from them, however just 1 last question - will I have to wait for it to cool down again or can it be done with the engine warmish?

R Longmore

The system is pressurised, so just let the engine cool before you remove the expansion bottle cap to fill up before you start bleeding (step 2).
Dave Livingstone

Thanks Dave.

I have now found out what my problem is.

Yesterday I followed your instructions to bleed the system (and yes there was air in it). Once I had done this I ran the engine for a while until it reached its normal operating temperature and then the reason for loosing coolant bacame all to obvious.

When the throttle is blipped I get quite an impressive jet of coolant from the split in the thick hose that goes to the casting on the cylinder head (behind the temperature sensor). It obviously only leaks once the thermostat has opened. I tried to bodge it using self amalgamating repair tape but the pressure in the system was too much for it, so I ended up coming back to the Midlands with the F on the back of a recovery wagon.

Oh well I better go and get a new hose so I can use my pride and joy again. Once again, thanks for your help.
R Longmore

Aah - the main engine outlet hose! Mine split there too and also only leaked coolant when under significant pressure i.e. engine quite hot.

The hose is about £30 from memory. I'm glad you've sorted that one.

Merry Xmas
Dave Livingstone

Sounds like good news to me.

SF
Scarlet Fever

Sounds similar to the hose failure on Ted's car during the last Treffen: http://www.mgf.ultimatemg.com/Treffen2003/day%205/day5_06.jpg

A cheaper fix than a blown head gasket!
Rob Bell

This thread was discussed between 20/12/2003 and 22/12/2003

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