m20 fan rumble noise?

[mcbonio]

Hey folks,
I'm coming close to the end of my e30 perfection quest, next on my list is my radiator fan.

When the car is on there's a front end rumble noise not from the engine, I'm almost certain its the fan, I'm not getting any over heating issues which I think can be related to a bad viscous coupling?

I'm thinking its the bearing on the fan itself.. can this fail or am I talking bollox?

[bss325i]

Most likely the water pump bearing as the viscous is attached to the water pump.

[mcbonio]

Water pump was changed with timing belt 20k ago, in 2008.

Could it still be this? Any way to testing the fan bearing or water pump bearing?

[clipper]

Water pump bearing shouldn't have failed after 20k miles.

Sure it's not the alternator bearings?
Mine has been making a "bearingy" sound for a while and I only pinpointed it to the alternator recently.

[Brianmoooore]

Water pump bearing shouldn't have failed after 20k miles.

Q Drive pump? 20k would be optimistic!
Centre bearing of the viscous can fail but this usually results in a wobbly fan blade if it's failed 'loose', or a noise like a small 'plane at take off if it's failed seized and you rev the engine.
Try running the engine for half a minute with the belt off to confirm the noise is related to something belt driven.
Is the belt too tight?
Do you have power steering?

[mcbonio]

Hey Brian,
Yeah the fan doesn't wobble or make the described sound, I do have power steering also. This seems fine however.

I'll take a video today and see if I can capture the sound. I'll try the stethoscope trick with a bar too.

Cheers guys.!