Hi all,

It's a while since I've been on here, the P38 has had a few bits done here and there, like blend motors, but in general for the last couple of years it's all be fine.

A couple of weeks ago I noticed a new ticking noise. It seems to be from the passenger side, it's not there when you first start the engine from cold, but starts after a couple of minutes, once it warms up.

A few years ago I partly stripped the engine down, to replace head gaskets, camshaft, lifters, etc and installed reconditioned heads from V8 developments, since then other than a noise that I've posted on here about before and seems to be somewhat common, it's been smooth and quiet.
Yesterday I did an oil change, as it is almost a year since the last one, despite only doing a couple of thousand miles since the last one. I hoped that fresh oil might have been all that way needed and the ticking would disappear, however unfortunately not.

Like most, I always have slipped liners in the back of my mind whenever I hear a noise that shouldn't be there. So to be sure, I did a quick coolant exhaust gases test with the coloured dye (was fine) and also checked all the spark plugs on the passenger side, but all were the same, no signs of water getting in. Plus when I had head gasket issues previously, I had coolant loss from over pressurising, a misfire and things, which I guess you'd expect if the issue was liner related.
At the moment other than the ticking noise everything seems to be okay, it runs fine and not using any coolant or oil.
Today I took the rocker cover off and then removed the rocker shaft, as I thought maybe it had a crack or damage, but I couldn't see anything wrong with it.

So I don't really know what to try next, the lifters were all new when I rebuilt it with the new camshaft, so I'd hope it wasn't a lifter, but I guess it could be. It could also still be the rocker arms or shaft too I guess. Worst case it could be a slipped liner, slapping up and down?

Here is a video of the noise, when warmed up, and with a gentle few revs - https://youtu.be/rVi6JLTqwg4?si=xwTyQqunoY5GN4s7

Any ideas what I should try next or anyone had similar?

What oil are you using? There' was a batch of rockers with pads that weren't properly hardened but that would be more of a single tap from one cylinder. The reconditioned heads would almost certainly have been skimmed so the lifter pre-load could be at the limit and you need shims under the rocker pedestals. But if that was the case I would expect it to have always been there unless it was right on the limit and now a little wear somewhere means they are now at the limit. See https://www.v8developments.co.uk/preload.htm and https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://rimmerbros.com/ItemFiles/Manuals/Rover%2520V8%2520Cam%2520Follower%2520Preload.pdf&ved=2ahUKEwixvpmhrNeTAxVbWUEAHdUxDyEQFnoECDQQAQ&usg=AOvVaw3mLg0YlXpGfbKlDj4rHFNf

Thanks Richard!

Well I use 10w-40, to be honest I always have and it's been fine, then I bought a couple of bottles earlier in the year in preparation for the next oil change as usual. Since the tapping started I've been reading about 10w-60, which if I didn't already have the 10w-40, I'd have given it a go this time.

When I rebuilt it, I stupidly decided not to test the preload and therefore didn't use any shims. I guess once I put everything back together and everything was running fine and quiet, I thought I'd not need to bother with shims. Since the rebuild which was I think about 3 years ago now, everything has been fine, no ticking, no coolant or oil use etc. The other noise that I've posted about before is lower down and I asked a Land Rover independent specialist (reluctantly had my ball joints done there, as I didn't have the time last year or tools to do them myself) and at first they said what noise, which is reassuring that it's a common thing with these V8s and then when I pointed it out, they reckon it is more likely from the gearbox and nothing to worry about, just a typical noise that some have.

I've been searching around online this morning and seen a few different people that had issues with the cups in the rockers being loose or excessively worn. Yesterday I was more focused on the pads and rockers themselves than the cups where the push rods sit.

I think I need to take the rocker cover back off and look deeper at the cups of the rockers and the rocker shaft.
Seen as most other things have been replaced over the last few years, maybe it's time to go for new rocker arms and shafts, as well as new push rods. Then I can at least rule them out and test the preload and install shims if needed.
Should I choose to go down the route of new rockers, what rockers have others opted for? Not so keen on the idea of Britpart ones, but looks like there aren't many options...

Your car should be too late to be affected by the rocker cup problem, but after 25 years who knows what bits are inside an engine. This TSB shows which ones had the problem.

To be honest I won't fit Britpart if it is something that is 'mission critical' so would be wary of using their rockers. Turners list alloy rockers but show them as out of stock but they also list steel ones described as aftermarket but with no mention of who made them. I'd also be inclined to take the rocker shaft off and closely inspect the shaft and rockers. Before unbolting it, check to see if any of the pushrods will rotate easily. If they do, that is a pre-load problem.

I agree that some always have a slight knock, my car has always had one and I've noticed it on others to a greater or lesser degree. Mine was still there after the engine was rebuilt by V8 Developments and more noticeable from under the car which made me also think gearbox or torque converter. However, after 454,185 miles my original gearbox died on me (actually it was the torque converter internals that had broken up) and it was replaced with a 4HP24 from a low mileage 4.6 and the noise is still there. So the only thing in that area that hasn't been replaced or rebuilt is the flywheel and I don't feel inclined to remove the gearbox or move the engine forward to replace it when it may make no difference.

Yeah that's the thing, at some point the car had a replacement engine, a number of years before I owned it. There is a receipt for engine replacement and labour, but no details on what it actually truly included or age/mileage of it. So no idea what the age is of the rockers.

When I stripped it down the other year I was pleasantly surprised by how clean it was under the valley cover and since the reconditioned heads and new camshaft went in, overall it's a really clean engine on the inside. In fact when I took the rocker cover off yesterday the heads look brand new still. I've only done probably 6k miles since the rebuild work and I run 90% on LPG and keep oil changes strictly to yearly.
That said the rocker arms and shafts are probably the most used looking parts now internally, at least top end side of things.

Yeah the other noise I've really stopped worrying about, I'm not fully convinced it's the gearbox to be honest, I always feel like the noise comes from further forward, so really not sure what the cause is and not too bothered anymore.
This new noise is more concerning, as it can be heard clearly with the bonnet shut and pretty loudly.

I shall take the rockers back out and inspect more closely over the next few days and decide where to go from there.

I suppose I worry too much about liners whenever I hear any noise :/

Do Thors have the same purge canister valve that GEMS ones do? Because that makes a fast tapping sound that is worryingly like a dropped liner, once the engine warms up and only at idle.

My P38 had a ticking noise for at least ten years. It was cured by having V8 Developments completely recondition the engine,

Good timing on this post. My 4.6 V8 has been ticking over the last 12k miles I've owned it. Sitting at 207k, it was rebuilt at 165k and has always had 20w50 fed. This could be either the camshaft or exhaust manifold (it ticks the second the engine starts), but I'd like to play with the oil as it's due for a change.

Will 10w40 suffice? I'm on the brink of ordering it, but would like some input.

Going thinner will only make it worse if it is oil related. If it was exhaust manifold, chances are it would get quieter as it heated the manifold up and go away once hot.

Gilbertd wrote:

Going thinner will only make it worse if it is oil related. If it was exhaust manifold, chances are it would get quieter as it heated the manifold up and go away once hot.

This is the sound - https://youtu.be/7DsdQQsvo9k

The second part, which is recorded from the footwell. The microphone does not pick it up well, but there is a subtle rattle as I accelerate. I've got myself booked in a few weeks to get this investigated. I do hope it's the exhaust gaskets.

Definitely doesn't sound like an exhaust leak. Sounds more mechanical.

Hmm, so an update to mine, I bought another rocker assembly set, so that I had spares of everything before I disassembled the rocker cover again. I found that one of the push rods spins freely on one rocker. When I look at the rocker it's not easily visible any damage really, but I suspect the ball head is slightly recessed. I swapped over to a full new shaft and rockers, as well as all new rods. All the rods are now firm and feel secure.

I started it up and it had an awful misfire. I plugged the nanocom in and it's misfiring on both cylinder 1 and 4, plus a few random misfires on other cylinders. It was fine before... I've just taken the rocker cover back off and run the engine with it off to check everything over. It seems okay, oil is pumping nicely and although it's not had chance to warm up there is no noticable tick. However the misfires are a new issue. It seems it can't be directly related, as cylinder 4 is on the opposite bank that I've not touched. I'm wondering if I damaged a wiring loom or what now... Any ideas where to start?