RangeRovers.net Forum banner

1 - 11 of 11 Posts

·
Registered
1995-2002 Range Rover P38A
Joined
·
690 Posts
Discussion Starter #1
4.0 noises are scaring me, prepare me for the worst (or best)

Hi folks, my 4.0 P38 is the first Range Rover I've owned, the first V8 I've owned and the first petrol-engined vehicle I've driven in years.

It has a tappy noise. It doesn't seem to be using water, the tappy noise is at half engine revs, it idles and pulls smoothly but it's a bit down on power.
The tappy noise is worse when warm (but present from cold) and goes away as soon as I increase the revs to even just a little off idle. There'[s no "puffing" from the oil filler. It's leaking oil badly but I suspect that's because the breathers collapse under vacuum.

It's done 168000 miles, so I suspect that the camshaft is worn. Is there an easy way to check that? I'm guessing pulling the rocker cover and winding the engine over by hand, and checking the rocker-to-valve clearance?

I *reeeally* hope it's not a slipping liner. I'm guessing that would tap once per revolution?
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
108 Posts
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

the tapping noise could be:

1. lifter or lifters not working properly
2. a worn camshaft or camshafts and/or the components which fix its placement in the block
3. sloppy rod/wrist pin function

and a few other things. the bottom line is the engine is old and getting tired even if it drives ok.

the only way to really eliminate it for certain is to tear the engine down and replace the worn from use items.
i seriously doubt you have anything to worry about other than the engine is getting worn and tired at the mileage you stated.

i have a 98 4.6 which ticks incessantly at idle once it warms up going away at higher revs. annoying at traffic lights in the summer. my mileage is a bit less than your and i never hesitate to drive the car because of the ticking. at some point i have will have to tear it down and rebuild it but for now i live with it considering the car gets less than 5000 miles a year put on it.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
690 Posts
Discussion Starter #3
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

Well that's a good start. It looks like it would be a couple hundred quid to get a new camshaft and tappets, and presumably rockers and shafts would be needed too. I'll keep driving, and keep an eye on it...
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
1,851 Posts
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

Hi

It could be dirt in your oil system because of overdue oil changes. The dirt prevents the non return valves in the tappets to close properly.
First try an engine flush with chemicals in the oil and replace the oil and filter. Follow instructions on the can.
You could add some dextron 3 transmission fluid to your oil to clean up the engine. If you open the oil cap on the engine and look inside you should see golden brown coated surfaces.

It could also be wear but a flush could get the tap to go away.

If you keep driving around with the tap (from tappet) eventually damage to the rockers and push rods will happen. These are cheap parts but beware of that when you continue to drive that you have them when you do the top rebuild.

Regards

Jos
 

·
Premium Member
Joined
·
1,340 Posts
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

Well that's a good start. It looks like it would be a couple hundred quid to get a new camshaft and tappets, and presumably rockers and shafts would be needed too. I'll keep driving, and keep an eye on it...
You'll probably be able to reuse the rocker assemblies. But you WILL have to change the timing gear, possibly both sprockets as well. The chains stretch and are generally past their best at 50k miles...
 

·
Registered
Joined
·
21 Posts
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

Hi

It could be dirt in your oil system because of overdue oil changes. The dirt prevents the non return valves in the tappets to close properly.
First try an engine flush with chemicals in the oil and replace the oil and filter. Follow instructions on the can.
You could add some dextron 3 transmission fluid to your oil to clean up the engine. If you open the oil cap on the engine and look inside you should see golden brown coated surfaces.

It could also be wear but a flush could get the tap to go away.

If you keep driving around with the tap (from tappet) eventually damage to the rockers and push rods will happen. These are cheap parts but beware of that when you continue to drive that you have them when you do the top rebuild.

Regards

Jos
Don't use ATF in your crankcase. It's not meant to be there. Any low viscosity motor oil will clean out your engine.

To those who say there's a higher detergent content in ATF, provide a copy of an unbiased oil analysis that proves this theory. You'll be hard pressed to find one, because ATF contains almost nothing in terms of detergents. Motor oils have a MUCH higher detergent content than ATF.

Also, I wouldn't do a chemical flush. Heaven forbid you let a chunk of something loose and it gets lodged somewhere it shouldn't be, and some part of your engine gets starved for oil, you'll be digging deep into your pockets for a new engine.

If you're worried about sludge, just run a good quality high mileage dino or a synthetic and run short OCI's, like 1500 to 2000 miles. That'll clean the engine out safely.
 

·
Administrator
Joined
·
27,805 Posts
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

So all the decades that me, my father, grandfather and their shops have used ATF to clean engines we have been wasting our time even though it is a proven method? Who knew.

For those of us with experience using ATF for cleaning I can share that it works very well and does not compromise lubrication like engine "flush" products. So weather it is low in cleaners or not I'll stick with it on high mileage rigs as I have done for 30+ years myself.
 

·
Registered
Joined
·
21 Posts
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

So all the decades that me, my father, grandfather and their shops have used ATF to clean engines we have been wasting our time even though it is a proven method? Who knew.

For those of us with experience using ATF for cleaning I can share that it works very well and does not compromise lubrication like engine "flush" products. So weather it is low in cleaners or not I'll stick with it on high mileage rigs as I have done for 30+ years myself.
Just because you've always done it that way doesn't make it right :)

The fact is, any low viscosity oil will do the job. What you're seeing with ATF is merely the thinning of the existing oil. ATF is not meant for crank cases, which is why I haven't put it there since I educated myself on the topic. Lots of folks believe that ATF has magical cleaning powers because of all the detergents in it- that's a myth.

To each his own, and I've never heard of an engine blowing up from use of ATF in the crankcase, but I'm telling you what I know from my research.

OP, I'd recommend you use 0W-20 if you're going to do a cleaning before changing your oil. It's cheaper, has a higher detergent content, and it's meant for use in a crankcase. After your 0W-20 flush, run short OCI's until you're satisfied with the reduction in noise/ reduced oil consumption/ etc, etc.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
1,219 Posts
So all the decades that me, my father, grandfather and their shops have used ATF to clean engines we have been wasting our time even though it is a proven method? Who knew.

For those of us with experience using ATF for cleaning I can share that it works very well and does not compromise lubrication like engine "flush" products. So weather it is low in cleaners or not I'll stick with it on high mileage rigs as I have done for 30+ years myself.
What procedure do you follow? Only I've seen varying methods posted on the net including totally replacing the oil with ATF, idling at 1500rpm then changing right down to adding a cupful before changes.
Funny, but I seem to remember my grandad doing this to the cars he used to service in his garage some years ago. Well he used to add something to the crankcase and it was red, suppose it could've been Redex, that used to be popular back then! Although I thought that used to go in the fuel tank.


Sent from AutoGuide.com Free App
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
1,365 Posts
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

I had the same.

Bought a refresh kit for camshaft, timing gear and oil pump.

When stripped down, the internals of the engine were found to be "covered in carbon" (I haven't seen it yet) and the piston clearances way too high, with no. 7 piston slapping badly probably causing the tapping. Liners ok, head gaskets fine (never been opened at 200+ k km). Heads being checked now.

No time to get it "overhauled" here (and risky), so I bought a short block from Turner in the UK.

No, I haven't told the wife yet and yes we can still afford to eat (just).

Moral - don't waste money and time changing bits unless you are certain what the problem is.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
325 Posts
Re: 4.0 noises are scaring me, prepare me for the worst (or best)

My old 4.0L back in the UK started with the tapping when hot, just before No7 piston made a bit for freedom. On stripdown, the liner had been slipping, with no other symptoms, and finally disintegrated.

Hope yours is and easier fix.
 
1 - 11 of 11 Posts
Top