Noise when accelerating

My Discovery TD5 is developing a shriek when accelerating. I suspect the turbo as easing the pedal stops the noise. What sort of a job will it be (is it possible) to check and replace the bearings in the turbo?

Sounds more like a loose/worn belt to me.

As Bob says, more likely a belt .. or bearings in alternator, power steering pump, water pump, could be loads of things, a shriek isn't much of a description .. :)

In my case the shriek was our lass ...

A "shriek" is the description of the noise I would associate with the clutch release bearing being past it's best. Lifting off would reduce the torque and thus the slippage. Are you riding/slipping the clutch as you pull away? Does operating the clutch affect it?

Be honest, some people will swear blind they do not ride/slip the clutch but an engine doing 2000rpm and the car 2mph belies that... B-)

I don't know for sure but I wouldn't expect turbo bearing to last very long at all if they "shrieked". The turbo spins and some silly RPM and the bearings have a fairly hefty supply of high pressure oil to cool/lubricate them.

It'll probably be a split intercooler hose letting air escape - a turbo vented to the outside world can certainly be described as shrieking.

Its the rabbit... you know.. the one you thought had made it to the other side. He's been trying to get his ass out of the grill for nearly a week now.

;0)

One mans shriek is another mans foxes mating call.. so my money in on the hose from the intercooler too.

Lee D

Thanks to all who replied. I had a new belt fitted at last service on the assumption it was that but it had no effect. The clutch is fully engaged during the shriek as it happens if I accelerate from a medium to a higher speed in any gear and is around 3000 rpm or so. Continuing at the same speed but with the accelerator eased off gets rid of the shriek and it comes back on putting my foot down again. It doesnt happen every time to the same degree and seems slightly influenced by outside air temp/moisture levels. The idea of a split hose sounds emininently feasible and I will look further into it. Hopefully it will be something so simple!

Completely off topic but strangely enough I went outside this morning and heard two foxes lining up for an encounter. They were just outside our garden and my engine shriek was nothing like theirs :-)

That's what happened to me. The split was very cunningly hidden right underneath the pipe in the most inaccessible spot.

My Discovery TD5 is developing a shriek when accelerating. I suspect the turbo as easing the pedal stops the noise. What sort of a job will it be (is it possible) to check and replace the bearings in the turbo?

Check for signs of soot around the manifold studs at the back of the engine, TD5's that have been re-mapped tend to cause the manifold to overheat and warp slightly, this gives the symptoms you describe.

Andy

.... Especially if the manifold studs/nuts are loose/missing! Look out for a cooked harness to the low oil pressure switch if any such evidence is found.

Noise is coming from the tin exhaust manifold gasket flapping at high frequency. Happens only when engine comes on boost. Your exhaust manifold is loose and leaking.

Remove exhaust manifold. Cut webbing from between feeders where it bolts onto head. Take to engine reconditioner and get them to skim it flat again. Replace with new gasket and check all studs... the end ones will be broken. BE CAREFUL RE-DRILLING AND TAPPING - you have only a couple of mm between oil/water jackets at rear of head and the are right at the side of the stud drilling.

-Craig, (in a very wet Queensland).

To follow up my original post and to possibly help others for the future. The problem proved to be two broken exhaust manifold studs. Drilling out and retapping plus a new gasket has solved the problem. Thanks for all the suggestions.

John

On or around Sun, 16 Jan 2011 10:29:50 +1300, EMB enlightened us thusly:

that's a point, must check mine. I get some intermittent turbo noise on that, too. Mind, it has had the EGR removed and a plain connection put in its place, plus a K&N filter, and a cunning box to make it go properly. It now shows 0.75 bar at about 1500 RPM and 1 bar at about 1750. And is a damned sight more driveable, and moreover uses no more diesel.

and at that, there are 3 more settings I've never bothered to try. It's running a nominal 20% power boost at present.