Moar overheating!

[Erick]

Alright alright.

M30 Overheating... Episode V. (Because I'm George Lucas like that)

So this time I got the M30 to stay cool and chill, so I managed to bleed the system. Awesome, driving around town is all good, runs VERY cool with the fan that's right now wired to the ignition (so always on).

Now, start taking the car sideways and things change. If the temperature is barely out of the blue, one 20 second pass will bring the temp to 1/4. Another pass it will jump to 1/2. Another pass it will go to 3/4. To keep the temp coming down I need to do massive cool down laps. Mind you this was in VERY rare 60 degree weather.

Any suggestions at where I should look at first with M30s? Any common flaws that I'm not being able to find through searching?

The whole reason why I went N/A was to avoid these overheatings I had on the turbo car, but it seems that boiling water haunts my drift cars.

Thanks,
Erick

[yert315]

I'm having similar issues. Does it get warm when traveling at lower speeds at ~3k rpm and up?

What fan are you running?

[Jean]

I am going to guess there is still air in the system. My car does not have an electrical fan on unless I am sitting in traffic, and then it's only on with a push of a button at 1/2 speed (I am using the stock a/c fan until I get my spal installed). Once I start moving, i can turn the fan off and temp always stays at 1/2 even if I am flogging the shit out of the car.

If it helps you any when I was working on my brothers m62 car and didn't bleed it good enough, it would quickly 'overheat' if I took left or right turns for long enough periods of time and would settle down very quickly.

My guess would be an air pocket.

[kylekrueger]

I have had major cooling issues with my m30 in the past. I think the Jean is probably right, make sure there are NO air bubbles in the cooling system. Also, one thing you can try is checking the thermostat. It is a possibility that under normal driving conditions the thermostat does not need to open up all the way to let full fresh coolant in all the time however under stressful driving conditions like drifting its possible that the thermostat is faulty and is not opening up all the way to let sufficient coolant into the engine.

So first I would drain the entire coolant system. Then check and make sure the thermostat is working properly and make sure there is nothing blocking the coolant passage ways. Then refill and re bleed the entire system. When bleeding make sure when you turn on the car that there is a steady stream of coolant running out of the bleeder screw. (Although I'm sure you already know that).

[Erick]

I'm having similar issues. Does it get warm when traveling at lower speeds at ~3k rpm and up?

What fan are you running?

Nope. Temperature stays very cool until I start pushing it.

Jean, in re-bleeding the system, any suggestions to empty the entire system? I remember when I drained the M30 to remove it from the e28, and after I believed it was empty, I still managed to see about 1-2 gallons spilling out as we pulled the motor and moved it around!

Also, is there a way to pressure bleed the coolant system to ensure all air is removed? Because if there is an air pocket, then it's really stuck there because we've gone to hell and back to make sure we properly bleed the system.

[jlevie]

You can't pressure bleed a cooling system, but a vacuum fill system will fill the cooling system and eliminate any air in the process. But i doubt that air is the problem here.

Drifting is a fairly low speed activity that makes a large demand on the engine and cooling system. Because the engine doesn't overheat in ordinary stop and go driving or when at speed, My suspicion is that your fan isn't providing enough airflow during a drift event. If you've recycled the aux fan for this that is almost a certainty, even if you've removed the A/C condensor.

A full shroud on the front of the radiator and a 2300cfm SPAL (or better) should solve the problem. An example of this would be one of the Zionsville Competition radiators

[E30SPDFRK]

Does the car heat up if you're getting on it but not going sideways?

[Erick]

A full shroud on the front of the radiator and a 2300cfm SPAL (or better) should solve the problem. An example of this would be one of the Zionsville Competition radiators

I'm on a 2700cfm SPAL pusher fan already, no shroud though, but although I'm sure it'll help some, it just sounds like it'll be a small patch to make up for another problem that is in no way addressed by the addition of a shroud.

My reason for saying that is that most of my drifting is above 40mph, and although I understand the concept of no direct airflow, there are e30s sliding around with all kinds of motors and turbos and they have no overheating issues with OEM or near OEM cooling setups.

Hell, my original turbo M20 was ironclad. Full OEM setup down to the clutch fan and I could sit doing a standing burnout on brand new tires till they popped on FL's worst humid/hot weather and it still wouldn't reach 1/2 way on the temp gauge.

[Erick]

Does the car heat up if you're getting on it but not going sideways?

Not really, but then again, I really dont think I ever floored it on a straight line. On the road it'd be impossible.... a cop from 20 miles away could hear me.... and I don't think I'd want to hear it myself. :p

[Jean]

I am serious when I say I can sit in traffic for a couple minutes with NO fan action AT ALL and be at 1/2...after a little bit of time it will climb and I hit the a/c fan at half speed. Once I start moving, 40mph provides more than enough air to cool it down to 1/2 w/o fan being on. So if you are drifting at 40mph AND you have a 2700 CFM FAN ON and you are still overheating then there is something wrong other than you FAN. When you throw your car around, if you have a nice air pocket it will show itself faster than if you are driving normally. This is kind of why I gave my m62 example...driving normally it would be fine, but if I take an on/off ramp at speed (more than enough air flow, plus with a brand new fan clutch) it would show itself. Took some time to get all the damn air out of the system.

Try this if you haven't already :

http://www.mye28.com/viewtopic.php?t=58368

Do you have a heater core in your system, or did you by-pass it? If you still do have it, the valve still works yes?

[Erick]

So if you are drifting at 40mph AND you have a 2700 CFM FAN ON and you are still overheating then there is something wrong other than you FAN. When you throw your car around, if you have a nice air pocket it will show itself faster than if you are driving normally. This is kind of why I gave my m62 example...driving normally it would be fine, but if I take an on/off ramp at speed (more than enough air flow, plus with a brand new fan clutch) it would show itself. Took some time to get all the damn air out of the system.

Try this if you haven't already :

http://www.mye28.com/viewtopic.php?t=58368

Do you have a heater core in your system, or did you by-pass it? If you still do have it, the valve still works yes?

My bad for not posting my setup... I guess I should've started with that. I have no heater core. I bypassed it.

I've bled my system a few times, just not as thorough as that one. Sounds a bit extreme, but desperate times call for desperate measures. It's just hard to believe that after all we've already done that there still might be an air pocket somewhere.

We were thinking that this old and aged M30 developed a blockage somewhere with enough deposits.

So you say go take the car around a few corners, and re-bleed the system?

[Omaliyo]

Dunno if this will help but when i bled my system, i didn't notice i had my coolant tank open.... turned off the car and a huge plume of smoke came out (burped the system) dunno if that was good or not but the car stopped heating up after that.....

[kylekrueger]

another thing you can try is instead of using the bleeder screw when bleeding you can try and use one of the banjo bolts to bleed it sometimes those bolts are slightly higher in elevation in which case the air bubble would be trapped at one of the banjo bolts and not the bleeder screw so try to bleed it there and see what happens.

[Erick]

Try this if you haven't already :

http://www.mye28.com/viewtopic.php?t=58368

Do you have a heater core in your system, or did you by-pass it? If you still do have it, the valve still works yes?

Ok, so my water pump took a crap last weekend and I just replaced it today. Bleed the system exactly as mentioned there. I have no heater.... it's completely bypassed.

Still same issue. I mean, I didn't go out drifting but I can tell the car is behaving the same exact way still.

The motor takes a while to warm up with the fan on (or takes a while even with the fan off for that matter). But once it warms up, even if it sits idling with the fan on, it cannot hold temperature. It slowly keeps creeping up.

I'd say from a cold start it takes 10-15 minutes, which by that time the motor is overheating already.

Driving it on the street makes it barely cool down. If you drive on the highway long enough it'll bring the temperature down significantly (below 1/4)

And once you push the car sideways it's over.

Seriously... I've been plagued with overheating issues for damn near 4 years now... first because of boost.... but now even N/A. It's becoming seriously frustrating at some times.

Any thoughts... suggestions? I have no thermostat, brand new water pump, 2700cfm SPAL fan.

Thanks in advance
Erick

[yert315]

it seems like an airflow issue. How are the fins on the radiator?