Thread: Engine idling noise

Originally Posted by Steiner

So I got the engine mounts done at 4wdIndustries in Maitland the other week. Sounds like a completely new car! While I was there, I got them to check out the rattling noise. They think it may be the viscous fan bearing inside the timing case. Life's been super busy so haven't had a chance to take it back there, instead I tried a more local option in newcastle. They think replacing the belt tensioner & power steering pump will fix it. Who to believe..

4wdIndustries only recently replaced the belt tensioner when they did my harmonic balancer a few months ago so that doesn't seem likely. The invoice says $66 so it must be an aftermarket part as genuine is double that. Even then, it shouldn't go in 4 months..

I'd like to take the fan & belt off myself to check but I don't have a tool to hold the clutch. I know a bunch of people on here have made the tool themselves, Is there a post around here with a drawing to make one? I may be able to make one at work next week.

So for $66 the part will be a non-OEM pattern part of sometimes (not always) questionable quality. So yes could have failed - or could just be rattling as it flexes. Once the engine rpm increases the belt tension increases and the noise goes away.

4wdIndustries sell both the more expensive OEM and the cheaper Aftermarket part.

To check - don’t need any special tools. Leave the fan on and release the tension on the belt tensioner using a 15mm ring spanner and remove the belt. Easy to do - just google it.

Once off you can check all the pulleys and idlers all spin freely and feel smooth, and you can check the belt tensioner for any free play or noise when you flex it.

You can also then move the belt aside and clear of any moving parts and do a very very short test run at idle with the belt off to confirm this gets rid of the noise.

If it is the belt tensioner, 4wdIndustries will honour their warranty and replace - probably with the more expensive OEM part the second time around.

So just want to update this thread with the solution.

Turns out it WAS the viscous fan bearing. Due to the excessive play and how bad it got, the timing case cover also needed to be replaced with a good second hand one.
That along with a replacement machined exhaust manifold and EGR blank to fix exhaust leaks. It sounds bloody great.

The tensioner also needs replacing under warranty. It was only 4 months old.

Thanks everyone for your input!