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Topic Review (Newest First)

  • 07-18-2010, 08:23 PM

    Re: Fan shroud, what part number?

    I wonder if the aux fan is supposed to run while doing 75mph?? And I guess my other question would be...can the aux fan really help at hwy speed? Maybe something with mine is faulty. I know mine kicks on at idle when engine starts to get hot. Would still like to get it like yours. Like you, I have changed coolant about 3 times the last four years.
  • 07-18-2010, 02:39 PM

    Re: Fan shroud, what part number?

    Shroud was genuine BMW. Happen to be at dealership getting R12 charge (this dealership still has 5 to 6 years worth of R12 for older cars) and asked parts to find 1981 shroud. I asked if it was specific to the year and he said that was the only one that comes up on computer. Seems like I got one off of ebay few years back and fan blades were hitting so I threw it away. When I put this new one on, the blades shaved a little of the shroud off on lower left hand side when I first started it. Good to go now with no contact. Sorry BG, I threw away part number tag attached to shroud.
  • 07-16-2010, 09:42 PM

    Fan shroud, what part number?

    Was the shroud a genuine BMW part? In what model was it originally used, possibly the 323? Maybe I'll try one although I don't have many cooling problems.

    On a 97 deg F. (38 C.) and miserable humid day last week, I saw the temperature gauge creep up to about 3/4. The problem was the auxiliary fan was not running. But I spun the fuse in the holder and the fan turned on again. As long as the extra fan is running, my gauge stays a bit below 1/2, even at 75 mph. In winter, the temperature gauge is almost the same. I've changed antifreeze every two years since the car was new.
  • 07-16-2010, 09:28 AM

    Re: Over Heating: Auxillary Fan?

    My fan comes on with the was mentioned, not sure if it ever comes on without AC being on. Can share this....when I first got the 81 320i, I worked on getting it cooled down more. New thermostat (evidently there are 2 different temp settings)..I have forgotten what degree I purchased, but I purchased the one needed for hot weather. New radiator, fan blade, system has been flushed, and last week installed a fan shroud (new, $50 from dealership). So, I have done everything there is to do.
    In non summer month, car runs a little above 1/4 on gauge.
    These hot summer months (87+ degrees)...commuting to work 40 runs just under 1/2 on gauge, with AC on tooling down hwy at 75 it will creep up to almost and sometimes 3/4 but go no further unless I push car to 80 then it will budge a hair, but for the most part remain at 3/4. The fan shroud has actually helped a little bit. As long as it doesnt go over 3/4 I am comfortable keeping the AC on for 40 miles. When I shut AC off and resume residential driving the guage will drop to a little below 1/2..........ideling at a drive few the aux fan will kick on...hope this helps.
  • 07-10-2010, 10:31 AM

    Re: Over Heating: Auxillary Fan?

    TJ was right, there should be a thermostat in the radiator which will control the fan if the temperature gets too high. That said, on my 1981, I do not recall the auxiliary fan ever turning on if the AC was not on. I think you may have a cooling problem such as sludge in the radiator. Try a thorough flush and install new antifreeze. Use the kind for aluminum engines. Let us know how it works as this is valuable information.
  • 07-06-2010, 01:25 AM

    Re: Over Heating: Auxillary Fan?

    Check the bottom of the radiator, on the driver`s side. Are there two prongs with wires connected? If so, then when that switch closes the fan should come on (assuming the switch actually works, as well as any fuse or relay in the fan circuit). If there is nothing connected there, there should at least be a threaded hole in the radiator with a plug in it, where a switch can be fitted.

    Aside from that, flushing the radiator and blowing off the outside of it might help it to cool more effectively.
  • 07-03-2010, 04:30 PM

    Over Heating: Auxillary Fan?

    Hello All,

    My '81 320 normally runs at the halfway mark on the gauge. However, even on a cool day, the needle moves toward the 3/4 mark. On hot days or slow traffic, it creeps up even more. I usually pull over and let the engine cool off for about two hours.

    I have a dumb question. Is the Auxiliary Fan supposed to come on automatically without the AC turned on? If it is supposed to come on, but it doesn't, how do I go about finding out why it won't turn on.

    Thank you.

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