Liqui Moly Tappet Stop Noise

[Spetz]

My tappets are making a ticking noise. Not horrible, but still quite audible.

Does this do any harm to the engine? ie, are the valves being damaged or anything?

And, how does the Liqui Moly Tappet Stop noise work?
I know that generally these tappet additives thicken the oil and hence quieten things down, however liqui-moly claims that it does not affect oil viscosity?

 

[SwampSurvivor]

Which engine is it? Does it have a history of being noisey?

 

[zach1900]

Hydraulic valves?

 

[Olas]

Are they hydraulic or shimmed? You might need to set the lash, replace them or just live with it.
The LM product might be a detergent? Hydro lifters can seize in some cases..

 

[HerrStig]

Originally Posted By: Spetz
My tappets are making a ticking noise. Not horrible, but still quite audible.

Does this do any harm to the engine? ie, are the valves being damaged or anything?

And, how does the Liqui Moly Tappet Stop noise work?
I know that generally these tappet additives thicken the oil and hence quieten things down, however liqui-moly claims that it does not affect oil viscosity?
Anyone got a real old can of STP to send this guy?

 

[buck91]

I had some tapping in the Oldsmobile 3.5L. When I ran Kreen in the oil to try to address oil burning from coked rings the tapping went away. Still burns a ton of oil, though.

 

[zach1900]

Mechanical valves should make noise. No Noise could mean they are to tight.

 

[Spetz]

Sorry guys for not providing all the info.
Here it is:
Car is a 2003 Mitsubishi Diamante (6G74 motor)
Tappets are hydraulic
I have had them out and cleaned them in diesel. They all seemed to be operating fine but I guess under pressure they are leaking a tiny bit

So as per the original post, does this do harm to the valves or anything?

 

[Trav]

Cleaning them in diesel wont do anything if there is varnish inside, you need a solvent like carb cleaner and soak them.

Edit: make sure you pump them a few times with the cleaner in there then pump them up with oil before reinstalling.

 

[HerrStig]

Tapping usually indicates "excessive" clearance which won't hurt anything short term. "Tight" valves with less than the required clearance can cause problems.

 

[Spetz]

Trav, the engine did have varnish inside. I don't want to remove them again to clean them (if I do remove them I will replace them). Will any additive clean them out and make them quiet?
I used some tappet additives before that did quieten them down.

HerrStig, do you mean there will be long term damage?

 

[dennishiip]

LM MOS2 quieted start up valve clatter in my old Mercedes with hydraulic lifters.

 

[Falcon_LS]

With a Mitsubishi 6G series engine, allow the engine and oil to reach operating tempertaure and rev the engine at idle gradually to 3,000 rpm over the course of 15 seconds. Allow the engine to idle for an additioanl 15 seconds and go for a second round. If, after 8 rounds, the HLA's are still noisy, you may wish to try the additive. If that doesn't help, you will need to replace them. Not as expensive or difficult to do, but still a bit of a painful job.

 

[Spetz]

Falcon, does that really work? I think this may be the process if you put new lifters without oil into the motor.

It's not too expensive, and I have taken them out before to do valve stem seals so I am confident in doing the job

 

[Falcon_LS]

It's worked for me in the past on a couple 6G72 12-valves and 6G74s. New OE HLA's are already pre-lubed from the factory.

 

[Spetz]

I don't quite understand why they tick though. Presumably it means they are leaking oil and compressing under the force of the valve spring?
When mine were out there was no indication that either one of them was faulty. But from what I can tell only 1 of them is actually faulty at this stage.
How can I diagnose which one it is? Can I try compressing them in a vice as a test?

 

[Falcon_LS]

The performance of hydraulic lifters greatly depends on oil pressure and the quality of the oil used. Over time, it not uncommon for them to become clogged with sludge, etc. and start ticking or worse, affect valve performance.

When you install the lifters, you have to make sure you can compress them by hand - if you can't, you need to relieve the pressure. Mitsubishi revised HLA's a number of times - the earlier versions have a smaller oil exit that is smaller than the fill hole, so it traps a lot of gunk from the oil, which causes the ticking. Personally, I would get the latest version and replace all of them, instead of trying to figure out which one is ticking. The others will probably not be far behind.

 

[Spetz]

I already have the 3mm hole lifters.
I cleaned them in diesel as per the manual (ie, submerged in diesel, then depress the ball bearing and then start pumping the lifter a few times) and then primed them with the diesel.

On start up there was one really loud tick which went away, so I think there is one lifter that is making the ticking noise.

Do you know if Melling lifters are good?
And will leaving the ticking lifter do any damage to the engine? The tick is not particularly loud, but it is very obvious.
I bought some LiquiMoly tappet quiet to test out.

 

[Spetz]

Hi guys,

So I ended up buying and using this tappet quiet from Liqui Moly.

They claim that it does not affect oil viscosity, however it is clearly very thick when pouring it out of the can.

Also currently (at only about 60 miles post oil change and addition of the liqui moly additive) the engine is slightly quieter but not by much. I remember when I used some other tappet noise additive (I think Wynns or something) it seemed to have a greater effect. That was about 20,000 miles ago though.