Nobimmer 694 Report post Posted February 21, 2007 After getting the car back from mechs a few days ago and thinking it would be the last of my problems,it is now overheating Basicly,start it.Drive it for about 15 mins from cold and it'll get to half way.Then stop at a traffic light for more than a minute and it starts going up.Turn the heaters on full and it find's it's way back down to half way.Drive along sucking in air and it will go down from half way about 1mm. So essentially,only overheats when idleing. Any ideas? Cheers Ashkan Quote Share this post Link to post Share on other sites
nz320i 0 Report post Posted February 21, 2007 (edited) ive had a mild bit of that before, i bleed and bleed the system till it came right, make sure heater is on hot and on full when bleeding the cooling systems, its very simple btw, maybe an air trap? i replaced my radiator and water pump but it may be something really simple.look on the net and e30zone.co.uk and pelican parts Edited February 21, 2007 by nz320i Quote Share this post Link to post Share on other sites
RvT 9 Report post Posted February 21, 2007 Had the same issue in a 1990 535. It turned out to be a worn clutch on the radiator fan motor. Essentially, when the car is driving, air passes thru the radiator and cools it down. When the car stops, the fan motor kicks in and cools it down. Not sure if your motor has a fan belt only or a clutch in behind the fan. If it is a belt driven fan only, could be a slipping belt ? If it is clutch driven, then it is stuffed. Easiest way to test it is to try to stop the fan with a cloth wrapped around your hand - that is how the mechanic in Paris tested it for me. If it stops easily by hand, the clutch needs replacement. Quote Share this post Link to post Share on other sites
Nobimmer 694 Report post Posted February 21, 2007 Well it is belt driven and don't know about the clutch. Just remembered too that about a day after getting the car back it started getting hot so I stopped and had a look to see what was wrong and the fan had gotten stuck in one of those little bits of steel that runs from the top of the rad to the bottom of the rad. Pulled it out of there and drove back home with the heater on.Think fan might be stuffed?But from where? Still spins and stuff and have no idea how fast/slow it was spinning before to compare. Quote Share this post Link to post Share on other sites
Guest Ken Report post Posted February 21, 2007 Well it is belt driven and don't know about the clutch. Just remembered too that about a day after getting the car back it started getting hot so I stopped and had a look to see what was wrong and the fan had gotten stuck in one of those little bits of steel that runs from the top of the rad to the bottom of the rad. Pulled it out of there and drove back home with the heater on.Think fan might be stuffed?But from where? Still spins and stuff and have no idea how fast/slow it was spinning before to compare. Had basically the same problem which was the fan clutch. Just give a fan blade a quick push - if it spins freely = new clutch required. If it barely moves 1/8 to 1/4 of a turn then not the fan clutch. If you are going to have to replace it, don't forget that the 32mm nut is a left-hand thread! Quote Share this post Link to post Share on other sites
ED1RTY 2 Report post Posted February 21, 2007 Yea i had the same problem with the fan clutch. Take it down to Heiko at german automotive and get him to have a quick look ashkan, He'll tell you straight away what it is. Quote Share this post Link to post Share on other sites
325GRANT 0 Report post Posted February 21, 2007 sounds like an air block open bleed valve jack up the back of the car chuck the hose into it and leave it pumping water through. this happens every time i empty my radiator Quote Share this post Link to post Share on other sites
Nobimmer 694 Report post Posted February 21, 2007 Fan doesnt spin freely,well u flick it once and it will spin like an 8th of a turn,then flick it again it spins another 8th,flick it again and it'll spin a quarter...nahmean? Kinda like if you were spinning a non straight wheel on a pivot. I'll take it to Heiko,see what he says. Quote Share this post Link to post Share on other sites
Nobimmer 694 Report post Posted February 22, 2007 Well dont RVT and Ken.Right on the money. Diagnosis,fan coupling somewhere in there was rooted and hence not working as it should be. Should be done tommorow and motor should hooopefully be mint again. Quote Share this post Link to post Share on other sites
Guest Ken Report post Posted February 22, 2007 Well dont RVT and Ken.Right on the money. Diagnosis,fan coupling somewhere in there was rooted and hence not working as it should be. Should be done tommorow and motor should hooopefully be mint again. Great to have a "happy" BM (+ owner) back on the road! Quote Share this post Link to post Share on other sites
