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bill salmon
03-06-2005, 05:47 AM
After replacing rad hoses, I heard noises on the test drive like a flock of sqwarking birds under the hood. I thought water pump is dying now, but no fluid loss. I noticed movement at the pulley when I revved up the engine. After shutting down, I tested for movement by wobbling the fan about. Seems to be too much play there-the whole shaft moves about. Is this a normal thing? During my test drive after replacing rad hoses, the temp soared, but after a rest, the temp for the return home was ok. So, what is the tip? Is it fan clutch, water pump, both maybe? Strange that no more fluid loss is happening.

shogun
03-06-2005, 06:08 AM
It looks like the fan clutch respect. visco clutch is on the way out.
If it is wobbling already, that is really not that good and could even damage more.
H3re I copied some of the test methods people use:
quote:
My own test for fan clutch is this.
I wrap a thick towel a few times around my hand. With the car running and warmed up after driving, I gently put the towel wrapped hand on the spinning fan blade. If the fan clutch is shot, it will stop spinning quickly and with little pressure and no risk to the fan blades or your hand. If the clutch is locked-up, it will not stop and therfore is good. Be careful. It doesn't have to be a dangerous test if you use a light touch.
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Another fan test
I was overheating and tried the paper towel trick and found my fan clutch was bad, bought a new OEM, only to find they all are easy to stop unless they are really hot.

What I found, and maybe this is what you are doing, was that the fan clutch works by ambient heat. (duh) BUT, if the hood is open/up, no matter how hot the engine gets, the fan clutch won't do much. BUT, if you run the engine until hot -- just driving around for a few minutes -- then stop and let it sit with the hood closed for maybe 10 minutes, the ambient heat will have the fan clutch tight as a drum. Now open the hood and crank the engine and the fan should blow your hat off.

And it will probably quit within one minute. Its darn loud when its engaged. I now know the sound it makes and notice the greater air flow under the car that I can reach down and feel while sitting in the car with the door open, and realize that it is usually engaged when I first crank it, then it quits just a moment later. Even first thing in the morning when its cold.
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unquote

bill salmon
03-06-2005, 06:52 AM
Thanks,Shogun.
I just started up again, and there is grinding noise as well as the sreaching noise. Say the fan is taken out of the equation, as there is no play with it on the shaft. The pulley is moving about with the engine running. If you grab it and move it about, everything moves with it. I'll try your fan test tomorrow.

shogun
03-06-2005, 07:43 AM
I have read last year about some cases that the fan clutch bearing and/or the water pump had play. By this the fan also had play and damaged the radiator. On another board in USA I also read that one of the fan blades damaged the hood after coming off.
On my website there is a German language tech explanation about car parts. That also explains how the visco clutch works. Here is the link. Under the pic there are German words like Motor kalt etc. Click on these words and you see that the pic will change to to cold, warm etc.
click here. (http://www.kfz-tech.de/ViskoluefterZ.htm)

The water pump is also available on the after sales market, cheaper than from the dealer.
I changed my water pump so far once and the total mileage is about 65K.
If you want to change the water pump, on my website go to evansweb and /or to gale's page.

bill salmon
03-12-2005, 12:13 AM
I tried the tests for the fan and I was just about convinced that was the problem. But the pulley was moving too and at the end of it all, it turned out to be the water pump. I took an after market one from repco, so I guess I wait now to see what happens. I'm back on the road again and cruising. Thanks for the tips and links.


I have read last year about some cases that the fan clutch bearing and/or the water pump had play. By this the fan also had play and damaged the radiator. On another board in USA I also read that one of the fan blades damaged the hood after coming off.
On my website there is a German language tech explanation about car parts. That also explains how the visco clutch works. Here is the link. Under the pic there are German words like Motor kalt etc. Click on these words and you see that the pic will change to to cold, warm etc.
click here. (http://www.kfz-tech.de/ViskoluefterZ.htm)

The water pump is also available on the after sales market, cheaper than from the dealer.
I changed my water pump so far once and the total mileage is about 65K.
If you want to change the water pump, on my website go to evansweb and /or to gale's page.

csarm@sbcglobal.net
04-17-2006, 09:34 AM
Does anyone out there know where I can find some instructions on how to remove a water pump for a 1988 735I.

shogun
04-17-2006, 12:57 PM
On my website, check that site out.
Here is a direct link to the water pump change
http://evansweb.info/articles/2003/01/18/water-pump-replacement

csarm@sbcglobal.net
04-23-2006, 06:27 PM
Thanks alot for the info. I appreciate it very much.

AllGo'n'Show
04-23-2006, 08:28 PM
Very easy and quick to do, make sur eu go tthe new pump and gasket handy cause u will have the old out and be ready for the new in no time.

BTW its a good idea to change the small rad hose the connects to the waterpump while your at it. The system is always partially drained, half the work is done, why not save urself some trouble later and do it now? Worth the extra 5 minutes and $10