Thread: Worn camshaft?

I just had a thought.
have you looked at the flex plate being cracked?
That would make clang clang noises and vary with load , and be worst at idle.
Regards Philip A

Thanks PhilipA. Seems that only removing the inlet manifold will give an answer. As a next step I will try to run the engine without the serpentine belt and try to track the noise from the front of the engine.

Originally Posted by Pedro_The_Swift

as Phillip says,
it wont be connected to compression,

it IS idling/running on all 8?
(wheres that sound file--)

The sound file is here (first at idle with no load (no noise), then idle under load (rattling noise) and at the end 1000rpm with load):

http://muj.optol.cz/janousek/LR/cam-idle_plus_1000.wav

I can hear clicking noise (probably lifters) and more loud rattling noise which is half the frequency of engine rpm.

Originally Posted by PhilipA

I just had a thought.
have you looked at the flex plate being cracked?
That would make clang clang noises and vary with load , and be worst at idle.
Regards Philip A

Do you mean the plate used to fit the camshaft? I think it is called thrust plate in RAVE, is this the plate you mean? Please could you specify?

Id be shutting down each cylinder one at a time by pulling the injector plug lead as well as backing the timing of a touch.

to me it sounds halfway between pinging and big end knock if its a combustion related problem on one pot its only going to turn up at 1/2 crank speed because it only fires every second turn of the crank.

Id also look for a blown out exhaust manifold and if you have a spot thermometer check each port of the exhaust manifold for temp, if everything is good then all should hit the same temp at the same time. if ones getting there quicker than the rest or its not getting to the same temp then thats the pot with the problem.

best of luck.

the flex plat is the bit that connects the torque converter to the crank. think lightweight flywheel.

Originally Posted by Blknight.aus

the flex plat is the bit that connects the torque converter to the crank. think lightweight flywheel.

OK, first of all I have a manual transmission. There is a drive plate which is probably something similar. Anyway it seems to me that the noise is not comming from clutch, rather from engine, and if it would, I would expect noise at engine rpm and not half rpm.

crank shaft noises can occour at lots of different multiples of crank RPM due to the harmonics thing.

I still think a cylinder by cylinder shut down to identify which part of the engine is causing the problem is a good idea as is running the engine with the rocker covers off.

if its valve train related 90% of the time you can spot it in the movement of ther rocker arms or by scoping them with a metal rod/touching them.

Originally Posted by jiri_j

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.

That sort of covers Daves suggestion

Originally Posted by jiri_j

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 coming 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 coming 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 immediately to camshaft.

.... I'm working from the noise off that sound file ....



... That "Death rattle" makes your engine sound like a Diesel ...

Is this statement correct ....
The rattle is not present on NO LOAD .... but is clearly heard on LOAD

In some respects it (Rattle) replicates a engine that has massive (too much) advance ... Can you check the timing on the D2 ...



When using the stethoscope .... It is an excellent tool ... You need to be patient with it, and place it in many spots, to get it to the heart of the noise


I doubt this next bit is the suspect ... But is possible
The other is a loose gudgeon pin (Piston) ... This can be checked for being suspect, without stripping the motor ... I can explain the method if required