andyVR6 0 Posted May 14, 2007 finally got round to doing something to my second C thats been sat in the corner of the garage for months without been touched. the only trouble is is when it gets up to around 70-80 degrees it throws all of the water out of the header tank and the top radiator hose fills with air. if i remove the return pipe from the radiator to the header it just belows out loads of steam. + the heaters just won't blow warm. i've had every single pipe off and checked for blockages the pumps working fine and up until it reaches 70 the water flows fine, no air in it at all. i've tried allsorts to get it to behave. any suggestions? Quote Share this post Link to post Share on other sites
corrado vr6 0 Posted May 15, 2007 wot colour is yr cap on your header tank sometimes the o-ring in the old black caps gets twisted inside the cap making it overheat, i had simular problem and was told to get a blue cap from vag not gsf!! or it could b yr heater matrix Quote Share this post Link to post Share on other sites
andyVR6 0 Posted May 15, 2007 its blue but it does it without the cap on Quote Share this post Link to post Share on other sites
corrado vr6 0 Posted May 15, 2007 the reason why it could b overheating with the cap off is because pressurised water doesnt boil so if you havent got your cap on it will boil over Quote Share this post Link to post Share on other sites
andyVR6 0 Posted May 16, 2007 it does it either way. my first thoughts were headgasket but it runs fine and until it throws the water out it doesn't lose any. its as if theres an air lock somewhere Quote Share this post Link to post Share on other sites
dubcharger 0 Posted May 16, 2007 it sounds like an air lock,possibly between the thermostat and cyl head, i would replace the thermostat asap as it could be gunked up and/or knackerd, you probably know this allready but when you fill the cooling system up make sure the heater control is set to warm Quote Share this post Link to post Share on other sites
andyVR6 0 Posted May 16, 2007 theres no thermostat in it now, n ive even bypassed the heater matrix and it sill does it. Quote Share this post Link to post Share on other sites
Lufbramatt 0 Posted May 16, 2007 you probably know this allready but when you fill the cooling system up make sure the heater control is set to warm wouldnt make any different in a rado as theres always coolant flowing round the matrix, all the heater control does is move a flap in the heater air box that makes air blow through the matrix :wink: Quote Share this post Link to post Share on other sites
dubcharger 0 Posted May 16, 2007 you probably know this allready but when you fill the cooling system up make sure the heater control is set to warm wouldnt make any different in a rado as theres always coolant flowing round the matrix, all the heater control does is move a flap in the heater air box that makes air blow through the matrix :wink: nice1 m8 i didnt know that about the C', I was thinking of mk2 golf :roll: Quote Share this post Link to post Share on other sites
Lufbramatt 0 Posted May 16, 2007 :) thats one of the reasons why the matrixes fail so often, cos theyre always under full engine coolant pressure. mine went bang (or hiss lol) in the passat on a nice sunny day last summer :mad: Quote Share this post Link to post Share on other sites
Jim 2 Posted May 16, 2007 Hm.. it does sound like airlock type behavior. Problem is that running it with the cap off is all I had to do last time I changed the coolant on my car, however we were squeezing the radiator hoses the whole time as the car warmed up to force any air round and out of the system... Quote Share this post Link to post Share on other sites
andyVR6 0 Posted May 16, 2007 ive tried allsorts to get it to work now and its doing my head in. can some kind person post a pic up of the engine bay showing all the water pipes etc above the gearbox area. when i got the car everything was dumped in a heap in the car. just want to make sure theres nothing missing or routed wrongly. oh and it has got the wrong rad in it too its only a single core out of a golf but i would have thought it would just kick the fans in more often. Quote Share this post Link to post Share on other sites