Thread: Engine idling noise

Originally Posted by Pedro_The_Swift

The TD5's make lots of funny noises that sometimes turn out as exhaust manifold leaks,, lots of sound/vids on here that ended up being leaks...

Yeah okay, think it's time i sort out this manifold.

Originally Posted by Discofender

It just sounds like vibration and if it stops when you rev and not get louder then unlikely to be something internal......

Check your engine mounts, the rubber isolators wear out and then all sorts of vibrations happen. I chased an exhaust vibration replacing the whole thing eventually then checked and replaced engine and gearbox mounts. Runs quieter than ever.

Easy way to check engine mounts is with a small screw driver inserted in the small hole of the bottom mount, should go in about 1cm. My rubber was right down on the steel.....

Cheers Discofender

That's a good point, i found out my engine mounts were worn not long ago. I'll attend to that shortly.

Originally Posted by PhilipA

Sometimes if the accessory belt tensioner has not been replaced for a long time the spring will cause a clacking noise.

The engines vary a lot in revs at idle and you can see the tensioner moving backwards and forwards quite easily.
Regards PhilipA

The belt tensioner was actually replaced very recently. I'll check it out anyway.

Originally Posted by DazzaTD5

Umm which noise do you mean?

My guess is Harmonic balancer, sounds pretty clear just towards the end of the video.

*Does it make a sharp squeak when you turn it off?
*With the engine turned off (duh) grab one of the pulleys or the belt and see if you can move it in either direction and look at the bottom pulley, you will see the grooved part move with the belt but the outer part not move.
*Also get under engine and have a look at the back of the harmonic balancer, you will see the rubber is broken/breaking/cracked.

The harmonic balancer was also replaced a couple months ago. There's no squeak anymore when it's turned off so i'm assuming that hasn't failed already.

Thanks for the input everyone, appreciate it! I'm going to move forward with replacing the engine mounts and sorting out the exhaust manifold, will check back in here once I have.

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.

For $66 it will be a tensioner pulley only, not the tensioner itself. That sound like a tensioner rattle to me

Originally Posted by justinc

For $66 it will be a tensioner pulley only, not the tensioner itself. That sound like a tensioner rattle to me

Ah okay, I didn't know you could get the pulley by itself. Only thing is, the part number on the invoice is ERR6951A. Unless they've changed part numbers that's on their site as a dayco part: Land Rover TD5 Defender Discovery 2 Serpentine Drive Belt Tensioner ERR6951 Aftermarket

Originally Posted by Steiner

Ah okay, I didn't know you could get the pulley by itself. Only thing is, the part number on the invoice is ERR6951A. Unless they've changed part numbers that's on their site as a dayco part: Land Rover TD5 Defender Discovery 2 Serpentine Drive Belt Tensioner ERR6951 Aftermarket

Oh well, it's just I've never seen a tensioner sold for that price.

Originally Posted by justinc

Oh well, it's just I've never seen a tensioner sold for that price.

Ditto!

That's near $100 below trade

You will replace all the possible parts and then find something loose rattling against the engine. Heh heh....

Before you start throwing more parts at it - with the engine cold run it for a very very short period of time with the serpentine belt removed. You are doing this to prove the noise is from one of the half a dozen pulleys/bearings being driven off the drive belt that will now be idle during this test.

If you confirm it is one of the pulleys or bearings driven off the serpentine belt - then it is a case of elimination. A stethoscope (or long handle screw driver with your ear against the handle) can be useful to zero in on the noisy bearing. Edit: be very careful doing this as well.

In addition to the tensioner pulley - there are other bearings that tend to fail around the same time as the tensioner pulley. The power steering pump also has a bearing and is driven off the back of the water pump which has a dog clutch type drive that gets damaged and could chatter at low engine speed. Plus the alternator has a bearing and the viscous fan has a bearing. And there will be one or two idlers depending on if you have ACE.

It is rare you get away with only one part needing replacing once one starts to go - especially with age related failures.

But if the noise is not present with the serpentine belt is removed, then you start looking elsewhere. And don’t run it for long with the belt removed.

Originally Posted by justinc

Oh well, it's just I've never seen a tensioner sold for that price.

...except on eBay....