Three weekends ago Ken drained his cooling system, removed the water pump and all of the hoses on his M3...the car sat like this in the carport for a week.

The following weekend we replaced the waterpump and hoses, added coolant/distilled water, fired her up and attempted to "burp" her. As the car was running with the cap off the coolant reservoir, the car showed signs of overheating and started belching coolant out the reservoir opening...it was as if the thermostat was stuck and there was no circulation through the radiator...at that point we ran out of time and quit for the day.

Last weekend Ken replaced the thermostat and we tried the process again with the same results...this weekend we're going to check out the new waterpump to see of that may be the problem...

Anyone have any suggestions as to what may be going on?...

The same thing happen to us when we change the waterpump and hoses on a e36 M3. So what I did was put water thru the top radaitor hose and once I see it was fill. I quickly put back the hose and fill more water to the radaitor.
But also make sure that your heater is on and also dont forget to bleed the system.:)
Also you should also check the thermostat by feeling the top and bottom hoses if it is getting warm. Because if one of the hoses are still cold and the other one is hot. That means you have a stuck thermostat.
Dont also forget to check the radaitor if it is still good if you guys are using the old one.:) Because this happen to me when I had my Acura. I change all the hoses and waterpump and it would still overheat. So later I found out my radaitor was clogged. So once I put a new radaitor on and bleed the system. It ran at normal temp and never overheated again. :D

I am definitely interested in your outcome, my Dad and I will be doing the same job on my old E30 M3 in the next few weeks. The radiator on my car is not flowing well from just plain age, so a new one is going in.

it's irrepairably broken...just sell it to me for cheap already...i'll do you the favor of taking it off your hands...:D

i dunno if E30 is same as E36, but gotta get the nose up higher to bleed properly on the E36...

it's irrepairably broken...just sell it to me for cheap already...i'll do you the favor of taking it off your hands...:D

i dunno if E30 is same as E36, but gotta get the nose up higher to bleed properly on the E36...
Yup, try bleeding it on an incline. Or try this.

http://i7.photobucket.com/albums/y278/bokubo/funny-pictures-boobs-too-big-0cc.jpg

I've always bled the cooling system of any car on an incline...bubbles escape much faster this way.

Yup, try bleeding it on an incline. Or try this.

http://i7.photobucket.com/albums/y278/bokubo/funny-pictures-boobs-too-big-0cc.jpg


front of the car was on jackstands, heater was on and radiator is not that old...

interesting... check the clutch fan, is it turning on? bad clutch fan possible... blockage inside the block itself... not very common, but does happen....

both upper/lower hoses getting hot?

interesting... check the clutch fan, is it turning on? bad clutch fan possible... blockage inside the block itself... not very common, but does happen....

both upper/lower hoses getting hot?

definitely hoping there is no obstacle in the block...upper hose gets warm, but is soft as if there is no coolant present...can't remember what the lower hose was doing...

if there is no coolant present, i would definately check the water pump, and something is not circulating.... its getting hot, meaning that some water has to be moving, but maybe not enough to keep everything cool

time to donate the car to me, i'll pay the towing.

time to donate the car to me, i'll pay the towing.

we'll let you know...;)

front of the car was on jackstands, heater was on and radiator is not that old...

Even though the radiator is not that old it can still be block or clogged. Because my Acura had a 2 year old radiator and it failed. The way I found out it was clogged was when I felt half of the radiator was getting hot and the other half of the radiator was still cold. Thats I how I knew it was clogged.
You guys should also check to make sure you didnt blew a headgasket.

time to donate the car to me, i'll pay the towing.

Or time to put in a s52 or s54 engine in it ! :D

Even though the radiator is not that old it can still be block or clogged. Because my Acura had a 2 year old radiator and it failed. The way I found out it was clogged was when I felt half of the radiator was getting hot and the other half of the radiator was still cold. Thats I how I knew it was clogged.
You guys should also check to make sure you didnt blew a headgasket.

not worried about the headgasket....unlike E36s and up, the E30M3 has a real temp gauge and we shut her down just a she went a little past halfway...

Or time to put in a s52 or s54 engine in it ! :D

that's blasphemy to a real E30M3 aficionado...:eek:

Gene,
Try bleeding it through the bleeder valve with the reservoir cap closed tightly.
Fill fluid from the reservoir with the bleeder valve open until fluid comes out of the bleeder valve.
Cap reservoir, close bleeder valve, take car for a short drive to bring temp up.
If it runs hot, open bleeder valve slowly until the bubbles stop coming out and an even flow of fluid starts to pour out of the bleeder valve.

The thermos usually are okay when new, but I have experienced 2 new water pumps that were bad and both were from the dealer....third times the charm I guess.

The S14 is a little different, there is no bleeder screw. It's trickier to do correctly, and is somewhat considered self-bleeding, but there is no way to get air out like on later BMWs. I used to squeeze the top hose with the heater on and the cap off, run the motor a bit and refill, but seems to have more going on with this car.

Hmmm...maybe just have the reservoir cap loose just enough to let the air out, as opposed to off and then aid it by squeezing the hose too.

I am definitely interested in your outcome, my Dad and I will be doing the same job on my old E30 M3 in the next few weeks. The radiator on my car is not flowing well from just plain age, so a new one is going in.

after changing the thermostat (the old one was still good) and several more burpings, the problem is fixed...Ken found the following on a msg board and we tried it, but don't know if it helped as our hose had coolant in it...

"I then removed the radiator hose from the top of the radiator. I did not loose any fluids which I thought was strange. I then poured water into this hose which leads directly to the thermostat. Cranked it up and the thermostat opened and all is well. I must have had air trapped on top of the thermostat which never brought the thermostat up to its opening temperature."

after changing the thermostat (the old one was still good) and several more burpings, the problem is fixed...Ken found the following on a msg board and we tried it, but don't know if it helped as our hose had coolant in it...

"I then removed the radiator hose from the top of the radiator. I did not loose any fluids which I thought was strange. I then poured water into this hose which leads directly to the thermostat. Cranked it up and the thermostat opened and all is well. I must have had air trapped on top of the thermostat which never brought the thermostat up to its opening temperature."
Mahalo for sharing!
Learn something everyday!