Help please!

[Kaz 64]

Hey everyone,

My e30 is overheating really badly (just as I got it road legal as well). I have looked through the other threads and tested things that were the problems for them and its still doing it.

I have done the following:

Checked Thermostat and Water pump, checked for leaks, and ran a hose through it to check for blocks.

Any other options that might be causing it to overheat?

I don't have a viscous fan as I replaced it with an electric fan a little while ago. Was this a good idea?

It doesn't take long to overheat at all, even when driving at 100kph. And its not using any coolant.

Its a 1989 320i.

Any help would be greatly appreciated,

Kaz

[Kaz 64]

Sorry if thats not enough info, not sure what else to add.

Any other possibilities if its not the thermostat, water pump, vicsous fan or a blockage?

[Jamez 2147483647]

viscous should only make a difference when going slow, so im thinking you've got something blocking a water channel in the engine or a cracked head

[Kaz 64]

I put the hose through all the pipes to check for blocks and to rinse out any crap if there was any in there and there wasn't. So possibly the head gaskets cracked?

[black mans wish 0]

Mate i had the same problem with my e30 and i replace the thermostat and coolant and even replaced the radiator with a brand new one with all the hoses and it would still over heat, then i found out that it was the fan, try putting back the factory fan.

hope that's any help.

cheers raj

[Kaz 64]

Did you have an electric fan instead?

[Kaz 64]

I put the electric fan in cause it used to overheat in traffic up in Auckland. If I put the standard fan back in it would go back to doing that.

[ashy_aye 3]

hey dude i had a simalar problem once and in the end i found out i just hadnt bleed the whole system properly and there was a air lock in there.

at the moment i have no viscous and two electric fans but dont ever use them around the street, it only gets hot enuff to use them when im use'n high revs with no air flow.

[ducatiss 1]

So long as your electric fan is coming on (and drawing enough air - you should feel it really blasting out the hot air) then the fan is not the problem. Also, if it is overheating at 100 km/h, that would also point to the fan NOT being the problem. Most likely an air lock - they can be tricky buggers to bleed sometimes. Possibly a cracked head though I think you would have noticed other symptoms if this was the issue. Could also still be the radiator - are you sure its completely clean?

When you say its overheating what is the car doing - is there steam/coolant spewing from somewhere? Can you hear it boiling? or is it just your temp gauge saying its over heating?

Did you check your thermostat in a pot of boiling water and watched it open fully before the water boiled?

Also check the hose going to your coolant expansion tank and the cap on the top.

Is the system pressurizing correctly?

As much detail as possible always helps.

[black mans wish 0]

na it was a standard fan um it jus went bad

[Guest FrantiC]

Yeah it will more than likely be your cooling system is not bled properly.

Did you bleed it properly ? Heater on hot and on full blast ? Front of car jacked up slightly to make the bleed screw highest point on the system helps bleed it better.

If it were a cracked head or haedgasket, You would more than likely be loosing abit of fluid not just overheating. And since it's at speed, the fan has nothing to do with it. Fan helps at low speeds when there is less air flowing through the radiator like when you aren't moving, so the fan helps air pass through. At 100kmph there is more than enough air passing through it...

How did you check your thermostat ?

[Kaz 64]

I tested the Thermostat by putting it in boiling water to see it open up. I also left it out of the car and it still overheated with no thermostat so its definately not that.

Ill try bleed it soon. Also I'm getting the head gasket tested tomorrow just incase there is a problem with it.

[pureboiracer 0]

I tested the Thermostat by putting it in boiling water to see it open up. I also left it out of the car and it still overheated with no thermostat so its definately not that.

Ill try bleed it soon. Also I'm getting the head gasket tested tomorrow just incase there is a problem with it.

E30 Thermostast are a double acting thermostat. the car will overheat if you do not run one. check that it is opening at the right temp. and just try and bleed it again. it definatly sounds like either an air lock or a stuck thermostat.

it is deffinatly not your fan, water pump, and leaks, and not a head or head gasket.

if the headgasket was crook you would see steam coming out of your exhaust and if the head was cracked your oil would be creamy. Also these 2 would not cause your car to over heat without using nearly all of your coolant.

Have you checked your radiator flow?

if you drill a small hole in the outside of your thermostat. maby 1 or 2mm it will help bleed the air out of it

[Kaz 64]

I took it down to get a test on the Head Gasket and it seems to be alright.

I just have one real noob question.

Since my brother took out the thermostat earlier, I drilled a small hole on the outside as said, but my problem is this:

He had to go somewhere for the weekend so I'm left to put it in myself. I just want to know which way the thermostat goes in the housing?

Thanks for your help! I'm really hoping this will sort out the problem.

[Jamez 2147483647]

flat side goes driver side, triangle side goes passenger side.

[Kaz 64]

Thanks, got it

Well I took it for a drive with the thermostat on and its doing something a bit odd.

While just driving around, the temperature gauge is between half and 3/4. If I accelerate kinda hard it goes up to just over 3/4 and if im breaking, it goes back down to just above half way. While its stationairy after I took it for a drive, the temperature gauge went right up to just below the red which was when I turned it off.

Something else that has happened is there is now water in the rubber pipes! There was never that before so I guess thats kinda an improvement.

Any suggestions of what else I should do? or any comments?

Thanks,

Kaz

[Kaz 64]

I have also bleed it out properly if that helps.

[QuickSilver 0]

If the pipes going IN to the thermostat are hot, and the pipes exiting the thermostat are cold. Then that clearly shows that the thermostat is not opening. If both in an outlet pipes are hot from the thermostat, the w/pumps fine, the heads fine, the radiator fine, etc etc then it can only be bleeding. BELIEVE ME WHEN I SAY THIS!

M20s are a BITCH to bleed. It once took me several DAYS to get mine bled, I am not kidding, I have never come across such a pain in the ass motor. Mine had a serious airlock, and what I ended up doing, is walking away frustrated, leaving it over night to cool down again. The next time I went to bleed it, I parked it up on an angle, drained all the coolant out one more time, filled the system up via the the rubber hoses, constantly squuzing them to get as many air bubbles out before I even started the car. Once this was done, and I took my sweet time, heater on full blast, it bled fairly quickly and without hassle.

Edit: Make sure all the hoses are in their right places, and without unusual kinks or bends that can impair water flow,

Edited May 13, 2009 by QuickSilver

[Kaz 64]

All the pipes were hot so thats a good thing.

I will try bleed it again on the angle tomorrow. I'm guessing its just got a pretty bad airlock in it. How do these get in there btw?

[QuickSilver 0]

they get in there when the coolant is removed, or flushed, or you take the thermostat out etc doing work on the cooling system, or the coolant runs low and air gets in the lines, theres plenty of ways for air to get into it, its not overly sealed off to the atmosphere

Edited May 13, 2009 by QuickSilver

[Guest FrantiC]

Is the actual car running rough, steam pouring out kinda overheating ? Or is it just your gauge ?

Ever thought if replacing the cluster sensor maybe (Could be a dodgy sensor all along giving you faulse reading of engine temp...)

Removing thermostat woudn't have helped at all but make the engine take longer to get to running temp, so in other words running richer for long which seriously kicks you in the nuts with fuel economy as it is incredibly sh*t.

[tire 10]

e30 temp gauges can play up. One of the common faults is a nut on the back of the dial on the back of the cluster comes loose making the ground bad. tighten to make ground good. idk worth a try

[|ncary 0]

A good way to get air out is loosen the bleed screw just so there is a trickle coming out, then drive around the block pretty hard, that'll flush the air out, works for me everytime. You will get a wet engine bay though