Thread: Worn camshaft?

Thats one horrible noise--

LR V8 camshafts are not the hardest things in the world,, but it wont be that,, it might be things rotating ON the camshaft, maybe a lifter?

what was replaced with the cam?
followers?

Camshaft was replaced together with hydraulic tappets (is this synonym to followers ), timing chain and gears.

IMHO camshaft noise will not change with the load on the engine,BUT an exhaust leak noise certainly will.
before you do any dismantling check your exhaust manifold gasket to head bolts and the flanges between the exhaust manifold and exhaust pipe. From the noise I think it is the latter.ie a blown gasket.

Regards Philip A

I checked for exhaust leaks already. At the manifold and also y-pipe gaskets. This is more serious. Something is banging loud in the engine at half the frequency of crankshaft. Metal to metal.

I think that camshaft has to work harder under load - there is more pressure inside the combustion chamber, hence more work to open/close valves. Anyway, the maint point here is that noise which I recorded was taken under load and with idling engine, this means there is not so much lubrication of the camshaft and lifters than at high rpm. Hence, this noise is more pronaunced.

Not likely to be camshaft and followers/lifters if they were replaced so recently but could possibly be valve gear related. Maybe a rocker or damaged push rod. Remove inlet manifold and rocker covers to check.

Originally Posted by jiri_j

I checked for exhaust leaks already. At the manifold and also y-pipe gaskets.

Yes .. I listened to your "Death rattle" sound file

Before you even think of dismantling ...

Half of those noises can be attributed to failed exhaust gaskets ... check the bolts of the "manifold to head" .... Chances are that you have been tightening them up prior on a regular basis, or they are loose (Don't discount blown gasket either)

Also .... That Rattle .... use a 700mm length of garden hose and stick 1 end in your ear ... Use the other end to track the noise (Stethoscope) .... You will be able to "pin point" the noise and the part ....

..... Tell us where you track it to

Cheers
Mike

The rocker arm pushrod seat in the 4.0L had an issue with coming loose from it's casting. Resultant noise was similar to a bigend rattling and would reverberate thru the engine making it hard to determine what it was.
I would remove the rocker gear first and check all the seats in the rockers. Get some new rocker bolts before you put them back on.
If you have damaged one, you may well want to check the pushrod and pop in a new one also. Generally pretty cheap.
Just a word of warning when removing rocker gear, loosen all the bolts and then individually by hand hold the pushrod down and press the rocker to "unstick" it from the rod. Nothing worse than dropping a pushrod down inside the valley... Makes lots more work to retrieve it.

Cheers


Andrew


Sent from my mobile tellingbone using rock carvings.

Originally Posted by mike 90 RR

Half of those noises can be attributed to failed exhaust gaskets ... check the bolts of the "manifold to head" .... Chances are that you have been tightening them up prior on a regular basis, or they are loose (Don't discount blown gasket either)

Also .... That Rattle .... use a 700mm length of garden hose and stick 1 end in your ear ... Use the other end to track the noise (Stethoscope) .... You will be able to "pin point" the noise and the part ....

Hi Mike, I did a compression test on all 8 cylinders and got 170+/-5 psi. I checked each exhaust manifold individually by running the engine on 7 cylinders. I haven't found any difference in the rattling noise when I disabled cylinders one by one.

I bought a stethoscope to track the noise, however it is very difficult to track it. I am pretty sure that the noise is not comming directly from the rocker covers. When I listen to the engine from top (upper inlet manifold), I can hear the noise, and also when I listen below the engine (sump pan). I have the feeling that the noise comming from below the engine is louder than from top. On the other hand the noise is at half frequency of crankshaft, so my mind turned immediatelly to camshaft.