So, I just replaced the water pump in my '94 318is with a Geba pump. Everything seemed to go smoothly. I replaced only the pump, belts, and coolant. The belts are tense to the specifications outlined in my Haynes manual. I refilled and bled the air out of the coolant as outlined with the heater on, etc. But now there is this whining noise that gets higher pitched and louder as the RPM's increase up to about 4000. It kind of makes the engine sound like my wife's MINI. It seems to be coming from the either the thermostat housing, the fan, or (hopefully not) the water pump itself. I'm also losing a very small amount of coolant when I drive it, and I can't tell where it's leaking. I'm hoping it's a small leak from a radiator hose (that I should have probably replaced) that's also letting air in the system causing the whining. But if anyone has had this happen and knows what it could be, please let me know what I should do. Any advice is more than welcome and greatly appreciated. Please Help! Rob
Not my area of expertise Rob - but, if no one pipes in, email Mike Miller, he should be able to offer some insight!
I would start by fixing what ever is leaking if any coolant is getting on those belts running it will cause a squealing noise. My other thing is I see a lot of tensioner and idler pulleys going bad on these cars. If you can replicate the noise and use a long screw driver and put it on different components and put you ear to the screw driver to see if you can find where the noise is coming from.
I'd agree. When my pulleys started screaming on my 318ic it was time to replace them. That being said, tighten your radiator hoses. if they still leak and are old, they're cheap enough to replace. this is a good time to do some preventive maintenance.