1998 BMW 740 is my water pump bad

1998 BMW 740
125,000 MILES • V8 • 2WD • AUTOMATIC
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VILLAGE131
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I just put on a new serpintine belt and it will not move, ( I am guessing becasue of the water pump)the water pump will not spin does that mean it is bad?
can I repair it or do I have to replace it?
also can you run the car without the thermostat until I get a new one or will that cause leaks?
Mar 15, 2009 at 7:44 PM
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RASMATAZ
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Yes you can run it w/o the Stat but if its stuck closed you gonna have a big problem. Also the coolant temperature sensor will give the computer the wrong input signals to control other components.

One way to test for a bad water pump is to squeeze the upper radiator hose when the engine is hot and idling. Careful, because the hose will be HOT! If you do not feel much coolant circulating through the hose when you rev the engine, the pump may be bad. The other cause might be a bad thermostat that is not opening properly (remove and inspect the thermostat), or a clogged radiator.
Mar 15, 2009 at 7:52 PM
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DOCHAGERTY
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If the pump is seized then replacement is required. Do not run the car without the thermostat, it is there to throttle the flow and without it the engine wont be properly served by the cooling system.
Mar 15, 2009 at 10:07 PM
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