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MG MGF Technical - Cause for MGF overheat/HGF....
|My 97 MGF has just is just about to have it's 3rd HGF. I've had HG replaced in January but the cause never clear. Three weeks later I suffered the 'hit the red' on the temperature gauge again. When I checked the coolant, it was full of oil - the HG hadn't gone as I had abandoned the car once I noticed the temperature. The garage diagnosed a probable crack in head and replaced the head. Two weeks later I start to notice the temp is increasing very quickly on short journeys (but has not hit red) so ... I take it on a longer spin and eh voila, it hit's red, and the coolant is again full of oil.|
The one thing that seems different to other HGF cases (I've spent all day reading)is that there is no water in the oil - when i check the dipstick it doen't have this 'mayo/honey' so no water has leaked into the oil - but I do have a coolant tank with a lot of oil in it and it's bubbling like mad. The mechanic thinks there may be a crack in either the head or the block and when it is running the oil leaks out as it's at higher pressure????? Any thoughts from anyone??
|Good grief! I hope you are not paying for what seems to be major incompetence by the garage mechanics. You must be really peeved!|
|Could be that the HG has failed around the oil channel that directs oil to the camshafts. That's what happened to my '96 18i.|
If you drop me your correct mail adress i can mail you a picture of what it looks like.
|Just an idea...|
Did they peform an oil change and engine flush after they fitted the new gasket. The mechanics should have done this approx. 200-500 miles after they changed the gasket as it takes some time for the coolant to be removed from the engine. How would they know, otherwise, when the oil/coolant contamination occurred? The oil in the coolant they found could have been from the original HGF just 3 weeks prior (if the flush was not done).
|Yep, I'm peeved - and getting more so every day ... I'm not even sure that there was a crack in the head when it was replaced - does oil in coolant usually indicate a crack somewhere or can there be another reason?|
HGF was in December, fixed in January, did about 400 miles, oil in coolant Feb( just overheated - HG didn't fail), new head Feb, did about 250 miles, even more oil in coolant March (same again - HG hasn't failed). It was flushed in Jan and in Feb - I reckon the quantity is too much to be residual. I'm relectant to let the mechanic replace head/block until I know what the cause is!!!
|Chech ou t the MX5 and the new MR2 Claudia.They will cure your problem.|
This thread was discussed between 25/04/2001 and 27/04/2001
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