Hydraulic lifters - Tappets

[Tanz]

A year ago one of my lifters was very noisy. So as I needed to change the cam belt anyway, I removed the lifters, cleaned them and followed the service notes for re-filling with oil apart from the bit that says 'use thin oil as engine oil is too viscous' . I did use engine oil and the plunger was firm - no movement. After replacing them the engine sounded worse. Not a ticking but a clattering noise. So today I have removed the hydraulic lifters again and when squeezing one between thumb and forefinger there is no movement which is as it should be according to the service notes. i.e. no air has got in. So what is wrong?
When filling the plunger assembly - as you press the ball valve to let oil in and air out, the internal spring pushes the plunger assembly to its full length. The ball valve is a one way valve so the plunger will stay that length. Is it possible that the clattering noise is due to the valve lifter being too long?

From Service notes;

[dapinky]

Phil,

If you have a look in the 'Manuals' section, there is a short video which demonstrates the refilling of the tappets.... it isn't very different to the printed manual, and sounds like what you've already done, but it may be worth a quick squint....

[Tanz]

Thanks for the quick reply Dave
Yes that's pretty much what I did but with engine oil. However I did take more time to get the air out than the guy in the video. The plunger was firm when I had finished. Does anyone know what thin oil he had in the bucket in the video?

[TorqueHorse]

Maybe EVEO (Extra Virgin Engine Oil)?

Seriously though, even though it says don't use engine oil, maybe that is implying the normal engine oil for our engine (5w-40)? And using a low viscosity like a 0w-20 oil or one of the specialty oil additives marketed for lifters from Liqui-moly, or Lucas, etc. might do the trick?

For what it is worth though, I recently cleaned and repacked my lifters, with the normal engine oil, and my clickety-clackety tappet noise went away, and sounded fine.

Does it sound the same at engine cold as well as once its gotten up to temp?

[Tanz]

Maybe EVEO (Extra Virgin Engine Oil)?


Does it sound the same at engine cold as well as once its gotten up to temp?

No - the noise reduces as the engine gets hot but is still a bit noisy if you rev it.
When the engine is cold it sounds terrible. A clattering noise - not just a noisy tapping but a proper clattering sound. When the engine reaches normal operating temperature the noise is much reduced but still there a bit. Next day when the engine is cold again the noise is back .

[Tanz]

Does anyone know what the correct size of the OD of the tappet bucket should be? The service notes say 38mm but that is obviously an error as they are nearer 30mm. Mine are a bit scored so worth checking before I put them back.

[M100-NC]

Does anyone know what the correct size of the OD of the tappet bucket should be? The service notes say 38mm but that is obviously an error as they are nearer 30mm. Mine are a bit scored so worth checking before I put them back.

You might want to try GM Part # 94380758 or The Isuzu part number 8943807580

[TorqueHorse]

When the engine is cold it sounds terrible. A clattering noise - not just a noisy tapping but a proper clattering sound. When the engine reaches normal operating temperature the noise is much reduced but still there a bit. Next day when the engine is cold again the noise is back .

Have you tried a compression test? But I guess from your post you probably have the top off right now. So then, I'd suggest taking a couple lifters apart again and draining and check the oil from them for any little dirty oil particles that could have broken loose when you cleaned the last time, but maybe hid in a nook and didn't get flushed out completely. Because the fact that it improves with heat, as the viscosity of the oil goes down and it can more easily flow in those little guys, (and its what you touched the last time in there) has me thinking that it is still related. But hey, its late here and I'm just arm chairing on a small piece of the picture. Good luck and let us know if you are able to get to the bottom of it.