Strange rattle starting from cold

[Mike Noc]

Originally Posted by roverbarmy

I had a noisy tappet on a K series 1.4 which had exactly the same symptoms. I used an engine flush and then used 5/40 instead of 10/40 oil ( it was worse in winter) - problem solved.
EDIT. Just listened/watched the video. Not a tappet! Sounds more purge valve? ??

Yes it doesn't sound like tappets - they usually have a nice even and regular beat when noisy.

[Dallas]

Originally Posted by SD1too

Wes; I've just listened to your video as well and you should investigate that immediately. It's not tappets or the purge valve (the latter only activates when the engine isn't cold anyway).

Try placing a stout screwdriver on the alternator casing with the handle touching your ear both when tthe noise is present and when it ceases.

Next I would start by removing the OSF wheel and wheel arch liner to inspect the auxiliary drive belt and tensioner/idler components. After that, take off that cambelt cover for an inspection.

Simon

Thanks Simon, I reckon its something to do with the cambelt, thats where the sound seems to be coming from.

TBH the car has always had that sound from cold, but it seems to be getting worst. I had the aux belt tensioner, idler and aux belt itself changed last year, that stopped the bearing noise which we think was the aux tensioner at fault.

It just seems strange the sound stops after 68 seconds, as if oil has reached the component that is rattling.

Do you know if there is a member/mechanic near me that would check this out for me, I would obviously pay for their service, I'm not familiar with the V6 cambelt. The trouble with garage services round this way, they are very expensive, and I will most probably get the same attitude as last time, its a Rover-scrap it.

[Elliott]

I agree as well, its not regular enough for a tappet and sounds wrong, But it does sound like a slack cambelt touching the plastic cover. Ford Mondeo's with the silver top Zetecs used sound like this when the belt wasn't tensioned properly on a cold engine.

Belt would get changed nice and quick on a hot engine then when the engine was cold the next day it would make a noise like this until it warmed up.. So your noise is probably going as the engine warms up, maybe it free's off the automatic tensioner? Or the block expands and tightens the belt enough to stop it touching.

[Dallas]

Originally Posted by Elliott

I agree as well, its not regular enough for a tappet and sounds wrong, But it does sound like a slack cambelt touching the plastic cover. Ford Mondeo's with the silver top Zetecs used sound like this when the belt wasn't tensioned properly on a cold engine.

Belt would get changed nice and quick on a hot engine then when the engine was cold the next day it would make a noise like this until it warmed up.. So your noise is probably going as the engine warms up, maybe it free's off the automatic tensioner? Or the block expands and tightens the belt enough to stop it touching.

Thanks Elliott, that does make sense. It does feel like something is hitting the cam cover, knocking/rattling.

Do you think any damage can be done?

[murphyv310]

Hi Wes.
The rattle is too irregular for a tappet. I'd also go with a slack belt flopping around.

[Dallas]

Thanks Trevor, so the belt is slack at first from cold, then tightens up after 30/60 seconds or so.

The belts were changed 25,000 miles ago, back in 2011. Do you think its worth getting the belts done now, or having the tension adjusted, or leave it alone until I get the belts done when due?

[Salad-Dodger]

If that was mine, I'd have a good look at the crankshaft damper as well. I know its not a diesel but you may be unlucky enough to have a daft one on a V6. Steve

[Elliott]

If it behaves like the Ford then they go on for ages like this with no problems, but as the belt was done in 2011 and is due every 6 years its nearly due anyway, so a replacement might be worth doing now, but I would include tensioner and water pump as well while it is apart.

Could be the last people to change it used tipex marks instead of slackening the cam wheels and using the correct locking device, as I believe the cam and cam wheels are keyless fittings for correct belt tension and timing.

[Lordy]

Dallas this is the Dave reporting, that noise sounds just like the probe when the timing belt was about to go, exactly the same noise, it would catch on the plastic and make a plastic contact, which sounds just like your video.

I say inspect asap don't leave to chance, the probe was a non interface engine which caused no damage which I was very lucky.

I'm, not sure about the KV6 tho.

[Lordy]

Originally Posted by Dallas

Thanks Trevor, so the belt is slack at first from cold, then tightens up after 30/60 seconds or so.

The belts were changed 25,000 miles ago, back in 2011. Do you think its worth getting the belts done now, or having the tension adjusted, or leave it alone until I get the belts done when due?

For good patrcaice and extra inusarnce that everything is spot on, if it is indeed the cam belts, replace them all and the tensioner as well for extra peicve of mind.