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JMI
06-22-2007, 10:28 AM
Been having slight overheating problem. Have changed water pump (Helu), new lower temperture thermostat (75 C), new expansion tank with this mod (http://www.bmwe34.net/e34main/trouble/Data/Overheating.jpg) from this website (http://www.bmwe34.net/e34main/trouble/overheating.htm) put in new fan clutch, replaced aux fan 2 temperture switch-fan works.
The radiator has 32,000 miles on it. Thinking of trying to flush it. Any good flushing/cleaning products I can add prior to flushing or any I should stay away from? Or is it a bad idea all together?

I'm running out of ideas.

Thanks

Jim

632 Regal
06-22-2007, 12:23 PM
Hey Jim, What kind of overheating issue you have? I doubt the rad is clogged unless theres a buttload of radiator stop leak products in there. You didnt mention replacing the temp sending unit, might give that a whirl?

JMI
06-22-2007, 02:33 PM
This is my original post (http://www.bimmer.info/forum/showthread.php?t=33122). The temp gauge is still acting pretty much the same (running between half and 3/4) mostly near straight up but sometimes going about halfway between halfway and 3/4. Maybe a slight improvment but hard to tell.
Have considered the temp gauge sender but have not purchased it yet. Will probably order it today.

Any more ideas are welcome.

Thanks

Jim

632 Regal
06-22-2007, 02:52 PM
I remember that thread, I think either your fan clutch is bad or the aux fans arent kicking in with the clutch being the first I would replace. Besides a clogged radiator which is unlikely there isn't much left...your getting closer :)

JMI
06-22-2007, 03:00 PM
Jeff,
As stated above fan clutch has been replaced and 2 temp aux fan switch has been replaced.
There is not much left except the radiator or is there somthing else I missing. The engine is well bled.

Jim

Dan in NZ
06-22-2007, 04:11 PM
I had similar symptoms with mine... Mostly temp at 12 o'clock, but would sometimes creep up in traffic or low speed driving. Replaced the fan clutch, no improvement. Had the radiator flow tested, and it was mostly blocked... Had it re cored, then a few months later it started leaking. Then replaced the radiator.

Don't discount the radiator, especially if it's old!