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MG Midget and Sprite Technical - Coolant Loss
|My car seems to have lost about 1/4 of its coolant with no visible signs of a leak. It had a new radiator and set of hoses in July and they seem to be watertight.|
Any suggestions on where/how to find a leak. I suppose it could be a HGF or leaking onto the hot engine block.
Any neat tricks for pressure testing a midget 1500 system?
|Flush the coolant and heating system thoroughly. Check and tighten every hose and clip meticulously, ensure the header internal pipe is not immersed in sediment, pressure test the header tank (put the cap on and blow down the pipe, replace cap if leaking, and if sure all is well go for a blast.|
Over a period of 3 months of repeating the above in varying degrees it eventually worked for me;
Blew the head gasket properly.
|Dave Squire (1500)|
|When I replaced the rad I flushed everything, and replaced the hoses. Everything was clean and free flowing. Think I need to pressure test the system somehow, pondering where and how to attach a bicycle pump.|
|I think that a bolt-in schrader valve, installed into a plastic filler plug would do the trick quite well.|
Anyone know what thread the filler is?
|I've found a pressure test will find a big leak but not always a small leak|
check you pressure cap as no visible signs (if correct) means its blowing out the overflow pipe of going through and out of the exhaust
you could also start your engine get it up to temperature and with the pressure cap off look for air bubbles
you could borrow or buy a compression tester
you can buy or borrow some thing like a Frost block test kit if you think it really might be HGF - http://www.frost.co.uk/block-testers.html
also see, this page, ignore title and very top of this web page - http://www.frost.co.uk/how-do-i-flush-and-refill-my-cooling-system you can borrow or buy a
a few possible signs of HGF
missing whilst running
loss of power
coolant in the oil (white mayonnaise but this can also be from short journeys only)
gases in the coolant
can runs hot
lost of coolant
these things are not always all present or noticeable at the beginning at least but are more noticeable later or with hindsight
|two reasons I use 4-LIFE (undiluted) coolant are that, main reason - it shows up even small leaks and where they originate and if the leak is from when the car is just hot or hot and cold, second - it turns yellow if you have gases in the coolant system|
but it will find weakness in the engine if they are there so best for rebuilt engines
This thread was discussed on 17/04/2013
This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.