Any advice on my crazy E30?

[Diotima]

Last week the car overheated. It turns out that a bearing on the fan had pinged off and cut through a hose. I had the fan, thermostat, water cap and hose replaced. All was fine for a few days. Yesterday the heater hose pinged off whilst driving. It was fixed and water topped up, the guy who fixed it suggested I leave the water cap loose, a little steam was coming out of the hood a few miles later but no problems. I tightened the water cap this morning after driving to work but on the way home the temp gage went to red after about 10 mins, no steam coming from hood but I was kinda worried something else was about to blow, but got home without any drama's. On pulling over the rev counter sky rocketed in park........this hasn't happened before....
The E30 is being a little crazy, any ideas, I'm taking it back to the garage tomorrow for further investigation but a heads up would be helpful

thanks

[witeshark]

Has the water pump been replaced?

[Diotima]

No, you think it should be?

[darkhorse737]

your mech must be living in the '1950-60's. them were the times when engines had humongous water pumps and you could run them with radiator caps open.

These engines are different. Water circulates based on a CLOSED pressure system where leaks or seepages of any form disable the efficiency of the water pump. you need to purge the air out of the cooling system in order for it to function correctly. I have posted several leads on how to bleed your system, or else the temp sensor on your t-head will be reading the temperature of steam... and that sure will send your temp guage way up there in teh NEZ(never exceed zone).

[Diotima]

Thanks Darkhorse, I've been reading your posts on this topic, you are an illumination of mechanical know how

thank you

[yammahamma]

^^^ I know, ole Darkhorse has replaced starmarvin...

[BMW325E]

This is the bleed procedure that has worked for me , in this order. The heater should be on while filling.

Jack the front of the vehicle up onto stands as high as possible,

Turn the ignition on,heater on fan setting 1 and temperature fully hot,

Remove the rad cap/expansion cap,remove the bleed screw from the rad and IF you have one the bleed screw from the thermostat housing,

Fill the radiator up and keep pouring till there are no more air bubbles coming out from the bleeds, when good then install bleeds and tighten down(don't snap them),ensure the rubber O-rings/seals are still on the screws/on the bleed holes.

Suck some water out so it's not full and then start the car

[Diotima]

thanks for the advice, really appreciated

update:
I left the house this morning, drove for about 3 minutes and the car just cut out and stopped, at the traffic lights FTL

Was turning over but not firing, after many, many tries left it and waited for 20 mins then it started again, much to my relief and the traffic jam behind me....

I pulled over to take a look somewhere less obstructive and the car was idling in park at 3000rpm but in drive normal

everything seemed in order again, the temp gage was rising pretty quick so I filled it with more water, then suddenly everything ok again, revs dropped to normal in park, the temp gage went down and off she went with no further probs....I am so confused now, just drove her home and its absolutely fine

Do you think it was just low on water so the temp sensor not reading properly? Would this make the car cut out the way it did after 3 mins and revs go up in idle like that?

[nukeduster]

Originally Posted by Diotima

thanks for the advice, really appreciated

update:
I left the house this morning, drove for about 3 minutes and the car just cut out and stopped, at the traffic lights FTL

Was turning over but not firing, after many, many tries left it and waited for 20 mins then it started again, much to my relief and the traffic jam behind me....

I pulled over to take a look somewhere less obstructive and the car was idling in park at 3000rpm but in drive normal

everything seemed in order again, the temp gage was rising pretty quick so I filled it with more water, then suddenly everything ok again, revs dropped to normal in park, the temp gage went down and off she went with no further probs....I am so confused now, just drove her home and its absolutely fine

Do you think it was just low on water so the temp sensor not reading properly? Would this make the car cut out the way it did after 3 mins and revs go up in idle like that?

you need to bleed your system properly. turn your heater to full hot, turn your cabin blower on full, and then open up your bleeder valve on the top of your engine on your thermostat. the 320i's bleeder off the top of my head should be right near the front of the engine, its a small 6mm bolt that you loosen up a bit while running the engine. bubbles and coolant should come out of there.

run the engine like that a while until nothing but coolant comes out of it. while the engine is still warming up, squeeze the radiator hoses to try to remove any excess bubbles that are in the system and force them to the bleeder.

once youre done with that whole process, wait for the engine to cool, then open up your overflow tank and top it off.