New Camshaft Noise

Hi all

Iv Pretty much had the top end rebuilt on my 4.0L V8 Defender.
New Camshaft, Followers, timing chain, push rods, rocker assembly the lot!

I did this as it was ticking from the top, worn camshaft i thought.

iv just got it back and the noise is better but still there, its only done 30 miles since done so i was wondering if it will take time to quieten down?
If so how long?

200 miles?

thanks alot!
Kristian

99% guaranteed it won't quieten down.

I assume you've eliminated the other obvious 4.0 V8 ticking noises like a cracked exhaust manifold, piston slap, head gasket blow, knackered valve spring, sticking valve, worn stem or god forbid a slipped liner?

Is the noise the same as before? Is it quieter but still there? Does it change with engine temp?

Although a good idea to do the top end on a V8 as they age, was the issue diagnosed or assumed to be cam/chain/general top end wear? From bitter experience I'd recommend that you stop chucking money you don't have at it and get a thorough diagnosis.

It went to my local independent for diagnosis and repair.
Iv got the receipt which states the reason for the work was to cure the noise.
they told me to run it a few hundred miles then bring it back for another listen.
if its not gone they can sort it!

On the plus side the "rebuild" does seem to have given me a bit more power.

kristian

its the same noise as before but it is definitely quieter. Only starts when warm and is only really noticeable at idle.

Ticking or tapping? From cold or as the engine warms up? At valve gear or piston speed?
If all the answers are the second choice then I hate to say it but it sounds (no pun intended) like a slipped liner, something that Land Rover was very tight-lipped about (even to it's own dealers) in the early nineties. It can effect all 94mm bore V8's & there's even been speculation that running on LPG can hasten the problem, due to increased combustion temperatures. Sorry to be negative, but I've been there & now my last three RRC's have been 3.5's

the slipped liner would generally show other symptoms too like over pressure in cooland leading to overheat!

A faulty fuel injector can tick as well..........
I have a ticking that comes and goes on mine, the occasional smear of gun gum on the manifold fixes it.

gavbriggs said:

the slipped liner would generally show other symptoms too like over pressure in cooland leading to overheat!

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Not always Gav, I had a 3.9 with this problem & ran it for hundreds of miles before I'd finally had enough of the noise (& people asking me if it was a diesel!) finally I bit the bullet had the block replaced.

could u please explain what u mean "gun gum on the manifold"???

cheers

norseman said:

Not always Gav, I had a 3.9 with this problem & ran it for hundreds of miles before I'd finally had enough of the noise (& people asking me if it was a diesel!) finally I bit the bullet had the block replaced.

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Hi norseman,
Interesting, I for one thought the the definitive symptom for a slipped liner was the overheating as well as a bit of noise.

What were your symptions to lead you to suspect the liner?

discool said:

Hi norseman,
Interesting, I for one thought the the definitive symptom for a slipped liner was the overheating as well as a bit of noise.

What were your symptions to lead you to suspect the liner?

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Just the noise! Independant workshop stripped the lump down & could'nt find anything wrong with the top end. Drove from Chelmsford to Lincoln & back one day (about 300ml) without any other problems. Stripped again & just one bloke noticed a slight lip 'twix liner & the top of the block on #3, much discussion later & a new 4.0l block (they were in short supply then as P38 V8's were slipping liners like there was no tomorrow, but LR still had it's corporate head in the sand) was fitted.

Change your rockers!!Much cheaper than messing about with slipped liner worries which it won't be!The ally rockers have steel inserts crimped in which loosen but can;t easily be spotted,I too had new cam tappets etc in my D2v8 only for it too still tap,LR did a recall on rockers so I thought it was worth a try £80 later I had a quiet engine!!

matchmetisse said:

Change your rockers!!Much cheaper than messing about with slipped liner worries which it won't be!The ally rockers have steel inserts crimped in which loosen but can;t easily be spotted,I too had new cam tappets etc in my D2v8 only for it too still tap,LR did a recall on rockers so I thought it was worth a try £80 later I had a quiet engine!!

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For the benifit of all: I notice you say your LR is a Disco2, therefore post '98. Would these rockers have been specified on older V8's as I don't recall this problem/solution being discussed in the past.

norseman said:

much discussion later & a new 4.0l block (

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Are slipped liners common on d2 v8's? I thought it was more of a 3.9 problem?
I am now driving with an eye on the temp guage and an ear in the engine bay!!!! such a relaxing drive

Yes the v8's with exception to some early ones that used pressed steel rockers use the same alloy rockers!The 4.0 and 3.9 are the same,with the exception of the inlet manifold and injection management,I think if you engine was going to suffer a slipped liner it would have done it by now!Change the rockers!!

fireman-andy said:

Are slipped liners common on d2 v8's? I thought it was more of a 3.9 problem?
I am now driving with an eye on the temp guage and an ear in the engine bay!!!! such a relaxing drive

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The 'slipped liner' syndrome can happen to any of the 94mm bore V8's (ie all bar the original 3.5) with the 4.6 the most prolific example. Head-in-the-sand attitude from LR whilst un-informed dealers were routinely changing head-gaskets under warranty. Caused by the alloy block (now with less meat since the increase in bore size from 88.9mm) surrounding the pressed-in steel liner cracking, resulting in the latter no longer being a tight fit & being dragged up & down by the piston. Suggested causes are many & varied, but high combustion chamber temperatures together with poor tooling at the factory seem to be the favorites. In 2002 I had it on good authority that some 4.6's were failing with as little as 20k on the clock! Having said all that, lets hope 'Matchmetisse' is right in your case.

104k on mine but that said it does run quietly (lpg system fitted) and even in this weather it never goes above 1/2 on temp gauge.

I haven't had it all my way tho.
in the 3 months I've had it
maf sensor
2 lambda sensors
rear discs
coil packs and leads
both sunroofs leaking (headlining removal)
10 wheel nuts knackered

joy o joy of lr ownership

One detail I forgot to mention in my ramblings about slipped liners. Bear in mind that the liner will move with the piston, whereas the camshaft rotates at half crankshaft speed. Listening to the 'speed' of the tap might give you a clue.

norseman said:

One detail I forgot to mention in my ramblings about slipped liners. Bear in mind that the liner will move with the piston, whereas the camshaft rotates at half crankshaft speed. Listening to the 'speed' of the tap might give you a clue.

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Interesting ramblings though so when the engine is on fool chat there's a hell of a racket from a sliped liner then and not the tic tic tic of a worn camshaft that I had on my 3.5RR after only 90,000 miles.

discool said:

Interesting ramblings though so when the engine is on fool chat there's a hell of a racket from a sliped liner then and not the tic tic tic of a worn camshaft that I had on my 3.5RR after only 90,000 miles.

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In fact noise from the moving liner at speed is pretty well blanked out by other noise's such as transmission, tyre & wind. The infamous 'tap' (rather than a tick) is most noticeable at idle or lower revs & is unlikely to be heard when the engine is cold. It becomes audible quite suddenly as the unit begins to warm up.