Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Bo Bo]

Three days after changing the cambelt I did a 250-odd mile round trip, the following day I had a slight rattling noise on start up which got worse when I put it into drive. It only lasts for a minute or so & gradually disappears as the car begins to gets warm.

I took it to my local garage, but of course by the time I got there the noise had gone. Got him to check that the Aux belt pulleys were OK & he said that belt is very tight & might be putting pressure on the waterpump & to monitor it. It’s got ever so slightly better, but not much.

I told a guy at work about it who spoke to his nephew (who works in service at a Vx dealers) & he said it sounds like a loose cambelt tensioner   (not having heard it). So that’s where the panic set in!!

Finally got round to taking the Aux belt off today (big thanks to Timbuk again) & the noise is not there when started, belt back on & the noise is back.

It looks like things are pointing to the waterpump (it wasn’t changed with the cambelt because I had a receipt for it being done a few thousand miles ago   ), but could it just be down to the belt being very tight?

[Marks DTM Calib]

With the aux belt off check for play in:

The water pump
Alternator
Aux tensioner pulley
Power steering pulley.

Does it go when you turn the aircon on/off?

[Bo Bo]

Hopefully Timbuk will be able to confirm when he gets online later (he did the poking around!), but the aircon made no difference & there was slight play in the waterpump pulley.

[Timbuk]

With the aux belt off check for play in:

The water pump
Alternator
Aux tensioner pulley
Power steering pulley.

Does it go when you turn the aircon on/off?

Alternator, Aux tensioner and power steering pulley's  all seem fine, Aircon pulley was ok but put up a bit of resistance, (don't know how free it should spin by hand) but no play, waterpump, hmmmm, not sure, seems ok but does make a very slight noise, nothing like the noise you can hear on start up though . Bo Bo's and my expert opinion are swaying us towards waterpump, but i did turn up with a gas bottle and four rolls of roofing felt in the back of the car so what do i know :-?

[Marks DTM Calib]

Are the bolts on the crank, water pump and power steering pump pulleys nice and tight....

[Timbuk]

Are the bolts on the crank, water pump and power steering pump pulleys nice and tight....

Yep, first thing he had checked at the garage

[Marks DTM Calib]

Good (done that before myself on a water pump pulley ).....is the tensioner moving at all (not the pulley, the spring assembly) when running showing one of the aux items going through a tight point?

[Timbuk]

Good (done that before myself on a water pump pulley ).....is the tensioner moving at all (not the pulley, the spring assembly) when running showing one of the aux items going through a tight point?

Not that i noticed, seems to be running true enough, couldn't see any movement. His belt is pretty tight though compared to mine, tensioner has to be moved fully to get it on

[Bo Bo]

Are the bolts on the crank, water pump and power steering pump pulleys nice and tight....

Yep, first thing he had checked at the garage

Confirmed, will check the tensioner again tomorrow, but sure it's OK.

[Matchless]

Had a similar problem on my dads 2.5 recently, water pump had some play so changed it, quieter but still noisy. Fitted a 2.0 aux belt to bypass the aircon...noise the same so not air con. Swapped the alternator and noise almost gone, remainder was the aux tensioner pulley bearing.

If the water pump was not changed at cambelt time then fit a new one, they are not too expensive and will outlast two belts.
There was no play or roughness in the alternator but when I stripped it later one of the balls in the rear bearing had a small piece missing from the surface and was causing the noise.

[Timbuk]

Is hard to pinpoint it with the belt on, sounds like the waterpump, but who knows :-/

[Bo Bo]

Had a similar problem on my dads 2.5 recently, water pump had some play so changed it, quieter but still noisy. Fitted a 2.0 aux belt to bypass the aircon...noise the same so not air con. Swapped the alternator and noise almost gone, remainder was the aux tensioner pulley bearing.

If the water pump was not changed at cambelt time then fit a new one, they are not too expensive and will outlast two belts.
There was no play or roughness in the alternator but when I stripped it later one of the balls in the rear bearing had a small piece missing from the surface and was causing the noise.

Cheers, I re-greased the aux tensioner bearing when doing the cambelt.

[Bo Bo]

I noticed last night on my way to work after about 1/4 mile I put the rear window heater on at a junction & the noise was back slightly, but couldn't hear it at the next junction.
So when I was leaving work this morning; I started up, put it gear & turned the rear heater on again & there was a slight change to the noise. Turned it off & put the lights on & again a slight change to the rattle.
I've also noticed some interference on the radio (MW) with the engine running, although this might have always been there & I'm just getting paranoid!
Not sure if I've said this before but I'm pretty sure the noise stops as soon as I move off, even when cold, although hard to tell from inside & under acceleration.

[Nickbat]

I noticed last night on my way to work after about 1/4 mile I put the rear window heater on at a junction & the noise was back slightly, but couldn't hear it at the next junction.
So when I was leaving work this morning; I started up, put it gear & turned the rear heater on again & there was a slight change to the noise. Turned it off & put the lights on & again a slight change to the rattle.
I've also noticed some interference on the radio (MW) with the engine running, although this might have always been there & I'm just getting paranoid!
Not sure if I've said this before but I'm pretty sure the noise stops as soon as I move off, even when cold, although hard to tell from inside & under acceleration.

Alternator bearings, perhaps? The HRW uses a lot of juice and the drawdown could be putting a strain on the unit. On the other hand, if you're getting interference on the radio, it could suggest a short somewhere. Either way, I think you're looking at an electrical problem.

[nixoro]

Are you sure its not the exhaust rattling on one of the heatshields or is it definately inside the engine bay where the noise is coming from. Might be more noticeable what with exhaust manifold near the front perhaps the noise maybe travelling up the exhaust so its heard in the engine bay.