Gus 5 Report post Posted November 16, 2006 have just done some work to sisters car...few bits and pieces now its overheating, hardcore have replaced the t stat and the waterpump, along with visco fan, and still no joy. as far as i can ascertain there is no air bubbles...bleed screw on the t stat housing runs coolant out, not air any thoughts, from race series guys? or anyone? current thoughts are a blocked hose somewhere (but why was it not doing before) blocked radiator (have a spare but as before) or worst case, a buggered head gasket. getting irritating.....help! Quote Share this post Link to post Share on other sites
Silver Fox 43 Report post Posted November 16, 2006 When you open the radiator when it's hot, is it fair chucking the water back, hardcore bubbling? Have been thru the same, found I had an air block even after bleeding etc. Had to end up taking the small bottom return water pipe off at the radiator end and jammed the garden hose up it, then turned the hose on and let it force water right thru. Replaced the hose after that and rebled, all good then, no more overheating, worth a shot. Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 16, 2006 is definately chucking water back did your little trick, water ran through fine, started to get warm and started bubbling out radiator. blocked radiator maybe? gonna chuck my spare one in...im using the auto one now that its manual, shouldnt have any effect? looks in really good nick too which is odd..wil whack my spare one in and see what happens any other ideas! Quote Share this post Link to post Share on other sites
Silver Fox 43 Report post Posted November 16, 2006 Only other thought would be to leave the thermostat out and see if it still overheats then, may run a little cool but won't do any short term harm, will let you know if water's circulating and eliminate the thermostat as a problem. Most mechanics will tell you that chucking shows an air block or blockage of some kind, as the water isn't able to circulate and so it builds up back pressure and blows back to the radiator. I doubt it's your radiator. Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 16, 2006 def sounds like it..how the hell do i find it though? cooling system is def bled well and put radiator in anyway...where do i start looking for blockages? Quote Share this post Link to post Share on other sites
Silver Fox 43 Report post Posted November 17, 2006 Would try the hose again, leave all other pipes on, open the radiator and the bleeder nipple and jam the garden hose in that small bottom hose, the 20mm one from the bottom of the rad. Wait until the water is flowing freely out the top of the rad and the bleeder, then reconnect the bottom hose and test again. My guess would still be air. Have you tried it with the thermostat out yet. Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 17, 2006 the water was flowing freely before, maybe not free enough? i will try the t stat first though...ah what a way to spend friday! Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 17, 2006 well have done the flush and the t stat removal...it still runs hot...not AS hot but 3/4 mark or just past. the visco fan i put in doesnt seem to be working either. when flushing the water ran through fine....didnt seem to have any problems at all. its still hot enough for me to feel the water/coolant boiling in the two main radiator pipes. any more ideas? might have to give up on this one! Quote Share this post Link to post Share on other sites
Guest Andrew Report post Posted November 17, 2006 well have done the flush and the t stat removal...it still runs hot...not AS hot but 3/4 mark or just past. the visco fan i put in doesnt seem to be working either. when flushing the water ran through fine....didnt seem to have any problems at all. its still hot enough for me to feel the water/coolant boiling in the two main radiator pipes. any more ideas? might have to give up on this one! new rad Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 17, 2006 put the iS one in...both rads are in really good nick...dont seem blocked from hosing either Quote Share this post Link to post Share on other sites
Silver Fox 43 Report post Posted November 17, 2006 Hey, let us know what the problem was when you get it soted please Gus. Did you fit a new waterpump? That would have to be the only other thing maybe? Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 17, 2006 sure have! will post up when it gets sorted Quote Share this post Link to post Share on other sites
gmccormack 0 Report post Posted November 17, 2006 Gus, you are putting the water in while the engine is running and the heater is on aren't you??? Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 23, 2006 ^^^^ - yep, and it has no heater (bypassed) its a head gasket...hopefully not cracked head..bugger! fun n games Quote Share this post Link to post Share on other sites
Silver Fox 43 Report post Posted November 23, 2006 Ouch, sorry to hear, I've done 3 now, 2 cracked one OK, Good luck. Quote Share this post Link to post Share on other sites
nz320i 0 Report post Posted November 23, 2006 a question- my car is back to running normal (relief!!) just did a mad bleed and its good now, but before the car gets right up the half way on temp gauge , i get little what look like aire bubbles in the oil on the dip stick.. really tiny ones, and then when its running at half temp it looks ok, coolant is all good, and oil looks good, what the!? Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 30, 2006 well replaced HG and rebuild head...still overheating...figuring its an air lock somewhere. am replacing a heatercore or valve...the PO said that it was the valve..anyway to get them checked? anyone got any 318 heater bits?? may just replace the valve and see how i go...the 318iS stuff is different so no help with the core there but it may just be valve its not too hard to get to anyway so no biggie..but anything that helps with the bleeding may save my sanity! Quote Share this post Link to post Share on other sites
will 169 Report post Posted November 30, 2006 Gus A few things to check... to do this, remove the cowling and the viscous fan, start the car and let it idle until the temp comes up. When the car is hot (normal temp on the gauge, before it overheats), grap both the top and bottom hoses going to the radiator. At this point, the temp should be almost the same in both hoses (at normal operating temp the hoses should still be cool enough for you to grip them for a short while without burning your hands unless you have delicate hands, but be cautious before you grip each pipe!) If there is a marked difference between the temp in the hoses, you have a flow problem. This can be caused by several things... 1. blocked radiator 2. air lock in system 3. faulty water pump 4. faulty thermostat The heater radiator in the car does help the cooling but generally is not critical. The BMW system in the E30 works with a valve that closes the flow through the heater radiator when cabin heating is not required, therefore the system should be able to be removed (blocked off) without causing the car to overheat. (No water will flow through it when the heater is off so it can't be critical to the cooling of the engine). Howeve, I would recommend that, if you remove it, that you join the 2 pipes so that you can get flow through them. Also, these pipes can help with filling the system and bleeding air from it. I have disconnected one in the past when battling to get a system to bleed and jammed a hose down it and forced water into the engine and out of the filler bottle.. A lot of early M40 motors were fitted with waterpumps with plastic impellors. These are very inclined to lose the impellor or wear the impellor fins off to the point that the pump no longer pumps. This would be my first port of call, remove the water pump and , if it has a plastic impellor, replace it with one with a metal impellor. If it has a metal impelloor, check that the impellor is firm on the shaft. I have seen metal impellors that have loostened on the shaft and spin freely. I don't think the thermostat is critical to the flow in the M40 motor, but check your new one to ensure it is functioning properly. I couldn't coun't how many time I have bought a new thermostat and found it faulty. Air locks are the difficult ones to get rid of sometimes. Use the bleed nipples on ther thermostat housing and the radiator, perhaps help it along with the method above using the heater hoses to force water in and also try jacking the car up in the front as high as you can get it to help expell air to the front of the motor and hopefully out. Hope this helps, if not, give me a yell and I will figure something else out for you. Will need more info then... cheers Will Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 30, 2006 hey will have replaced heater core now and re bled..i believe it is bled however could be wrong..is still overheating! top hose is boiling, bottom hose is stone cold... waterpump is new, thermostat new, headgasket and gaskets new...the radiator seems fine and i have tried two different ones any more ideas? have drilled a wee hole in thermostat to help with bleeding but it is still overheating, albeit much slower\\ how would i find a blockage? grr Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 30, 2006 also, water runs through the radiator with a hose fine, but the top half is hot and the bottom cold...normal cooling? i may try my other one Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted December 1, 2006 well thanks to wills excellent advice car is fine..the thermostat (new) was not working..with it removed and 1/2 a thermostat as a restrictor car seems to be running great that was fun!.....NOT Quote Share this post Link to post Share on other sites
will 169 Report post Posted December 2, 2006 This should be a lesson to all, ALWAYS check your new thermostat BEFORE you install it. Gus certainly will in future (I hope..?!?) Will Quote Share this post Link to post Share on other sites
bimmer boy 21 Report post Posted December 3, 2006 Was it you today I saw on the motorway around albany in a 318 gus? was in the black silvia on black dish that zoomed past Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted December 3, 2006 could have been my sister..mtech suspension, 14" weaves (im repainting the 15's), all red tails and smoked indicators? black facelift coupe, de badged. plate is DEK Quote Share this post Link to post Share on other sites
bimmer boy 21 Report post Posted December 3, 2006 Yeah possibly, either that or I should stop waving at strangers Quote Share this post Link to post Share on other sites
