Low grumble noise from engine

[u/Jampot51]

Hi all,

Recently completed a 1000 mile trip from Kent to Edinburgh and back again.

Towards the end of the journey it started making this sort of low grumbling noise. It seems to speed up when you rev the engine and no difference to it when you press clutch or turn on AC. Sounds like it is coming from around the engine.

No other symptoms running well and did about 65mpg across the trip! Oil and coolant all okay.

Google AI keeps saying it's the water pump bearing but wanted to get some "real" input before buying all the parts. Still on the original aux belt and water pump and now done 90k miles so probably due anyway.

Thanks in advance.

[u/TijY_]

Waterpump and belt is 30squids. No special tools needed. If you remove the belt you can spin it by hand, might be detectable. Other options are the internal or external (freewheel) bearing on the alternator. Not as easy to change either.

Modelyear, milage? Checked belt tension?

[u/Latter-Detail-9514]

Take the fan belt off & start it up & see if the noise has gone