Hydraulic Valve Lifter Additives - Recommendations?

Hydraulic Valve Lifter Additives - Recommendations?

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Discussion

v8s4me

Original Poster:

7,234 posts

218 months

Tuesday 23rd May 2017
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I've got a slight rattle as the revs slow to idle (3.9 V8). There's no noise when the engine revs or when it idles, just an annoying little rattle from the left bank as the revs drop. I'm wondering if it might be down to a couple of the hydraulic valve lifters getting lazy and if so would an additive help.

Any suggestions? (Apart from don't slow down laugh)

phillpot

17,105 posts

182 months

Tuesday 23rd May 2017
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v8s4me said:
Any suggestions?

phazed 11.83

21,844 posts

203 months

Tuesday 23rd May 2017
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Could be small ends.

ChimpOnGas

9,637 posts

178 months

Tuesday 23rd May 2017
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If you think about it your followers are acting on the cam lobes so sit low and quite central on the low and centrally mounted camshaft, given the way you describe where the sound is coming from it's therefore unlikely you have follower issues, if you are getting a rattle on one bank it's way more likely to be a missing pad on a rocker which is quite common. The problem with this theory is there's no real reason why it would only present on the overrun, if you'd lost a rocker pad the engine would likely rattle noticeably at idle too, in fact it would rattle always irrespective of how you drive.

Now, if you consider a piston engine is just a big air pump, when you decelerate you've closed the throttle but the engine will still pumping hard, on deceleration it's well understood there will be a very high state of vacuum in your plenum and inlet manifold but you need to accept there will be pressure changes in your exhaust system too. This is why we all notice a difference in our exhaust note on the overrun, and if your exhaust manifold gaskets are leaking this can sound just like a metallic rattle. So before you condemn your followers check your exhaust manifold to cylinder head sealing especially on the left bank where you say the rattle is coming from wink. While we're not trying to make power when decelerating air fuel ratios on the overrun are still very important, too much fuel to air and you'll suffer a rich misfire, too much air to fuel and you'll get all sorts of lean condition noises from your exhaust as you come off the throttle, noises that will be greatly amplified in one place if you have a leaking exhaust manifold gasket.

So based on your comment that the sound is only coming from one bank and only on the overrun, before you suspect your followers/valve gear I would definitely completely reassure yourself that your exhaust manifold on the left bank doesn't have a small leak which only becomes noticeable on deceleration.

v8s4me

Original Poster:

7,234 posts

218 months

Tuesday 23rd May 2017
quotequote all
Perhaps "on the over-run" was a poor way of describing it. The noise occurs not when the engine is under braking load but simply when the revs are dropping back to idle eg rolling up to a set of lights and lifting off, or after blipping the throttle when stationary. Also it only happens when the engine is hot.

I'd have thought, as you do, that if there was a rocker pad missing then the noise would be there all the time. The engine was rebuilt by Powers less than 10k ago and gets an oil and filter change every year so I'd like to think it wan't little ends.

I think there is a small air leak at the manifold but that is quite different (a higher note) and does sound more like a tappet.

ChimpOnGas

9,637 posts

178 months

Tuesday 23rd May 2017
quotequote all
There are others on the forum describing this rattle, some of them have also had a rebuild by the same engine builder, I'm not suggesting anything here I'm just pointing out you're not alone.

Little ends would/could make this noise.

If you haven't done so already surely the next step should be to take the car to your engine builder, go for a drive together so he can hear the noise for himself, and then see what he says?

I'm sure he'll know exactly what the noise is when he hears it, and clearly no respectable engine builder would ever suggest the noise is normal because there's no way RV8 engined Rovers, Range Rovers or TVRs ever made such noises from new or they wouldn't have sold many... that's for sure.

Good luck with it.


v8s4me

Original Poster:

7,234 posts

218 months

Tuesday 23rd May 2017
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ChimpOnGas said:
....If you haven't done so already surely the next step should be to take the car to your engine builder, go for a drive together so he can hear the noise for himself, and then see what he says?....
That's a 200 mile round trip and a tank of petrol. Food for thought though.

Classic Chim

12,424 posts

148 months

Tuesday 23rd May 2017
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Mine re built by Powers does that on occasion, 885 cam with new steel rockers.
As soon as I drive it proper hard it stops and only seems to be an issue ( if it is one) when I've been driving for months like a granny.
Compared to many engine mines silent and compared to a more aggressive cam it's very quiet.
Chimp talks of Rover etc but they never put big cams in their log pullers though did they! Ffs
I think Dom leaves some wiggle room on tolerances for when it's very hotbut I'm sure chimp can tell me I'm wrong.
Take it for a drive like how the cam and set up is designed (hard) and you tell me if it's quiet again.
I think all the low revs we do is not good and some sustained revvin pumps the lifters up properly and oil actually coats the cam. Splash fed remember!

v8s4me

Original Poster:

7,234 posts

218 months

Tuesday 23rd May 2017
quotequote all
Looking back at my paperwork I too have the TVR885 cam. On the invoice I have new liners, rings and hydraulic lifters but no mention of little ends. I seem to recall Dom telling me he'd throw in a set of pistons which might explain why there's no entry for these items on the invoice. Anyway, it's 16,000 miles old now not 10,000. Don't the miles fly by when you're having fun? biggrin

After a run back from Spa at a sustained 3,000rpm to 3,500rpm for several hours more or less non stop the rattle was still there but no worse than before. After the car has been standing during the winter it certainly rattles a bit until the lifters pump up so that's why I was thinking this little rattle is lifter related.

I'm sure you're right about the intermittent use our engines get and leaving them standing during the winter can't help.

I'm going to try this stuff at the weekend and see what happens....


Boosted LS1

21,167 posts

259 months

Tuesday 23rd May 2017
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It wouldn't be to time consuming to check the rocker arms and pushrod preloads. That's what I'd be inclined to do. I'd also listen with a hosepipe to see if I could narrow down the source.

macdeb

8,492 posts

254 months

Tuesday 23rd May 2017
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confused why would you think an additive would cure a mechanical noise? Must be well marketed. Is it a rattle when slowing and or revs declining after a push of the throttle at standstill? It will be more than likely as 'Phazed' says little ends or pre-loads pointing to lifters/cam/valves.

carsy

3,018 posts

164 months

Tuesday 23rd May 2017
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I cant see it being lifter or pre loads otherwise it would be there on tickover and all other rpm's. And not just the low rpm overrun.

What you are describing is classic little end noise. Quite common on the 5 litres but not so much so on the smaller engines.

Difficult to diagnose really even with the engine in bits because like you say its not there when cold and so when examining the little ends on the bench they appear fine.

Does it sound like this.

https://m.youtube.com/watch?v=hmNaT0_oDoE

v8s4me

Original Poster:

7,234 posts

218 months

Tuesday 23rd May 2017
quotequote all
macdeb said:
.....why would you think an additive would cure a mechanical noise?
Because the diesel additive I bought from them did exactly what it claimed to do.

macdeb said:
.....Is it a rattle when slowing and or revs declining after a push of the throttle at standstill?....
Revs declining after a push of the throttle at standstill.

v8s4me

Original Poster:

7,234 posts

218 months

Tuesday 23rd May 2017
quotequote all
carsy said:
.....Does it sound like this....
No. Definitely not. I'd be really worried if it sounded like that. I'll try and do a little video and post it to YouTube if it records the sound accurately.

hman

7,487 posts

193 months

Tuesday 23rd May 2017
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Msds says perchloroethylene (dry cleaning solvent) and kerosine.

I doibt that's going to help you sort your top end noise

PRTVR

7,073 posts

220 months

Wednesday 24th May 2017
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hman said:
Msds says perchloroethylene (dry cleaning solvent) and kerosine.

I doibt that's going to help you sort your top end noise
Not even if the top end noise is caused by a lazy lifter at the bottom ? It can do no harm to try and a pretty cheap option, all it would take is a slightly blocked oilway on one or two lifters to cause a problem.

Classic Chim

12,424 posts

148 months

Wednesday 24th May 2017
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I think this noise is related to oil as some days it does exactly the same thing coming to lights etc and other times it's very quiet and no noise is evident.
I instantly had a problem when I went to a different oil from the standard 10/40 semi and my valve train made a constant tap. Removed the brand new oil for the correct spec and it stopped instantly.
I'll reiterate what I said earlier, Dom expects these engines in our cars to be revved as a sportscar would be but in reality most of us burble about with the odd quick blast of acceleration then back to sensible revs, since the day my engine was built over 4 years ago it's made these odd noises at different times and I've worried greatly over it, been and asked him to listen on numerous occasions and he's always given it a good bill of health.
It makes these noises some days more than others yet every single time I drive it really hard, full bore almost to the limiter sustained as in drag racing or track driving the valve train goes totally quiet and that normally last for weeks after.
When I've brought this up before other owners have also said it's probably nothing to worry about which I didn't really like but Ive come to believe they are indeed correct and I'd not worry about it at all.
I do believe this constant slow driving is likely to lead to lazy oil feed here and there, maybe they do block slightly with older gritty oil.
It's been said before these engines don't really lube the cam under 1000 revs and it's not really splashing oil up at 1500 revs much better so constant use at lowish revs will possibly lead to low oil between cam and followers causing tapping or slightly loose tolerances.
Probably a load of old tosh but there's def a correlation between my valve train noises and how I've been driving it.
As it's virtually impossible to accelerate for long on the roads I try to keep my cam lubed by just running it at constant 4000 revs say in third gear everynow and then. Seems to work.

I personally wouldn't put anything other than the correct grade oil in it. smile


hman

7,487 posts

193 months

Wednesday 24th May 2017
quotequote all
PRTVR said:
hman said:
Msds says perchloroethylene (dry cleaning solvent) and kerosine.

I doibt that's going to help you sort your top end noise
Not even if the top end noise is caused by a lazy lifter at the bottom ? It can do no harm to try and a pretty cheap option, all it would take is a slightly blocked oilway on one or two lifters to cause a problem.
Q. If you put dry cleaning fluid and kerosine in your oil can you expect your oil to work as well as it would do if you hadn't added solvents to it?

A. No you cannot.


Pupp

12,206 posts

271 months

Wednesday 24th May 2017
quotequote all
If it's making a mechanical noise, oil supplements are not going to cure it... doesn't mean the noise means anything is 'wrong' necessarily, just that the mechanicals are operating noisily in some way. of course. if the noise has arbitrarily changed, then that might well indicate a problem.

The concept of the so called 'lazy lifter' is, I suspect, an idea floated by someone who has never taken one apart, nevermind given any thought to how they operate. Unless the engine is completely coked and/or has no oil pressure, they are not going to be 'lazy' in operation. Sure, after extended non-running, one or two parked against open valves might marginally bleed down and take a moment to re-pump but if they are losing extension on running, your problem is more fundamental than the lifters.

Little ends and/or rocker pads, even liner movement if not a top-hatted block...


Boosted LS1

21,167 posts

259 months

Wednesday 24th May 2017
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^ What he said. You won't block up an oil way on a v8 lifter, ever.