cooling system ooperation

[aston_jag_tech]

1989 COOLING SYSTEM. is the Viscous fan sufficient enough to cool the coolant. Running engine without a/c, 80-90°F?

Im having cooling issues. new H/G rebuilt head, New T-Stat, Newer Radiator and water pump, Hoses, Exp. tank, cap, Aux cooling fan and switch operate normally.

Car was ran pretty hot with blown headgsket, not sure if the water pump survived but the impellars are not plastic but steel yeah?

But, Im pretty much stuck on what other possibilities the cooling issue would be.

[632 Regal]

dude the clutch fan can cool a bus pulling Mayberry uphill in the Smokey mountains. You might have an airpocket or not enough coolant with wetting agent to do the job. Something obvious is at factor now.

[sal_park]

dude the clutch fan can cool a bus pulling Mayberry uphill in the Smokey mountains. You might have an airpocket or not enough coolant with wetting agent to do the job. Something obvious is at factor now.

*if* it's not broken - with the engine off there should be some resistance to turning it, but given the car runs a normal temperature when you're moving I suggest the cooling system (rad, pump, hoses etc) is fine but the crank powered fan is not up to the job when stationary because the clutch on it is broken.

Key point is - when the auxilary electric pusher fan kicks in to cool things down, does it cycle on/off/on/off or does it stay on until you stop the car ? Cycling on/off is correct as the cooling system can reduce the temperature of the engine by enough to get it back to normal (and hence the fan turns off), but if the pusher fan turns on and then does not cut out until you've stopped I think you've got bigger problem - i.e. you cooling system is not efficient enough to cool the engine down when the car is not moving (radiator not able to dissipate the heat quickly enough etc).

hth

sal

[Ferret]

Car was ran pretty hot with blown headgsket, not sure if the water pump survived but the impellars are not plastic but steel yeah?

Not sure if you mean that you *know* it's a steel pump or are asking *does it have a steel pump*

Regardless, if your hg had gone, I'd pull the pump and check it out - even the ally pumps can let go of their driveshaft...

[gmannino]

Most likely you have not bled the cooling system suffieciently. Since you are driving an 89, I can assume that its a M20 which is a pain in the ass to bled the cooling system. www.BMWe34.net has a good writeup on how to correctly do it. The Bentley manual will also describe it.

If you are getting a mixture of oil and water in your radiator it will look like chocolate milk. If you do see this oil is still leaking into the cooling system and you probably have a cracked head or possibly block but I doubt the block because its iron.

When they rebuilt the head they should have check for leaks and cracks.

[aston_jag_tech]

Thanks for the responses and insight.

Im confident the air is bled out properly. I DO want to inspect the waterpump after last weekends fun traffic driving expereince.

After 30minutes of driving freeway 80 mph I come to a hault and creep through traffic on the 91 west towards Riverside.

The temp gauge starts reading above normal and then inbetween normal and red. The aux fan comes on high, I turn the heat on and It is stable. Idiling, I then pull off the side of the freeway and rev it to about 3k. The temp gauge reads to around normal again. This was after a few minutes by the way.

Im suspecting a clog in the cooling system(Radiator, smaller hoses) Or the coolant pump is clogged and or the shaft is broken or the impellar is spinning on the shaft(thanks ferret for that info)

Forgot to mention earlier...Its an M30. B35 head, head rebuilt, pressuretested etc-perfect.


The cooling system is fine while the rpms are high...Suspecting flow of coolant is not up to spec.

[632 Regal]

I would agree to a possible clog in the rad if oil mixed in there. Other than that guess I would have to say the clutch is weak on the fan. These as everything else on these cars are over compensated for and shouldn't let it overheat unless of course as you mention... something else is wrong. Does it sound like a schoolbus when it gets hot?

Thanks for the responses and insight.

Im confident the air is bled out properly. I DO want to inspect the waterpump after last weekends fun traffic driving expereince.

After 30minutes of driving freeway 80 mph I come to a hault and creep through traffic on the 91 west towards Riverside.

The temp gauge starts reading above normal and then inbetween normal and red. The aux fan comes on high, I turn the heat on and It is stable. Idiling, I then pull off the side of the freeway and rev it to about 3k. The temp gauge reads to around normal again. This was after a few minutes by the way.

Im suspecting a clog in the cooling system(Radiator, smaller hoses) Or the coolant pump is clogged and or the shaft is broken or the impellar is spinning on the shaft(thanks ferret for that info)

Forgot to mention earlier...Its an M30. B35 head, head rebuilt, pressuretested etc-perfect.


The cooling system is fine while the rpms are high...Suspecting flow of coolant is not up to spec.

[aston_jag_tech]

Thanks for the respones.

Im definetely going to flush my radiator and remove my water pump and inspect. Also, clean my condensor and make sure there is nothing blocking the radiator.

The fan clutch is New. Bought from Bav Auto. It doesnt sound like it to much although when I increase RPMS the fan does start to spin faster. At which the fan should be spinning fast when hot and at idle to function as it should.

I dont think Oil and Coolant mixed but it is possible.

Maybe you guys could give some info on this....A few weeks ago I was checking temps of the hoses with a infrared gun and then I wanted to perform a block test to ensure the headgasket was ok when it got hot driving one day. So the car is running, normal temp(i have a large fan in front of the car) and I place the block tester on the coolant reservoir and I block of the coolant res. atmospheric vent. I pump the squeeze ball for the block tester and passes the test. but then the bubbles in the test disappear and then the squeeze ball is slightly sucked on the test tube. The cooling system was pulling itself into a minor vacuum. Now, the coolant hoses werent collapsed at all. Nothing collapsed. At this point I was on the track of restriction and or coolant circulation complications...

Thanks everyone.