Hydraulic tappet wierdness

[joshb]

I checked my tappets today (1.9 DG) and they were all screwed in much more than 1 1/2 turns from just touching the valves! I adjusted them to the 1 1/2 from touching as recommended on this forum but did i do the right thing or should i have left them as they were i.e screwed in loads more? I sounds ok when i just stared it btw.. any advice ? cheers

[Aidan]

1 1/4 - 1 1/2 seems to be the recommended preload on a worn engine, factory set is 2 but that's new

[joshb]

I am confused now.. a new engine/tappets requires the tappet tightened more than a worn engine??? how does that work then?

[kevtherev]

it's a couple of thou movement.. hardly matters

I'm sure you did, but make sure the tappets are pumped up before you adjust.

the amount of preload in the return sprng, in the tappet, is a debate that goes on.
personally I use two turns from zero lash.
if a tappet remains noisy then I would suspect a weak return spring in the tappet

[syncrosimon]

I have read in the American forums that adjustment should be done with a warm engine, not hot, just tepid, and when they are not making the clacking sound. Aftermarket ones are available from CB performance and is the top one of the two below.


So start the engine, run for a few minutes to allow the oil to thin enough to get through the little hole, and then adjust. This is why they clack when cold, as the oil is too thick to penetrate the internals of the mechanism.

Clacky lifters can also be attributed to a worn pressure relief valve, which is easy to replace, and also cures some buzzer of doom problems. A lazy spring reduces tick over pressure and prevents pressure build up in the lifters.

[Laurie]

I think you got your top and bottom mixed up Simon. The bottom one is the CB and the top is Genuine. Only worry is that the CB one will be Chinese. Whereas, with a checkover for scoring and a measure of the overall length, the genuine one is probably good for another 100,000.

Over adjustment will cause burnt valves.

My Dehler is currently running with spring, cup,ball and lower piston removed, but with 3 upper pistons in the bore and the clip, with .002" lash. Stock steel push rods.

[syncrosimon]

Could well have, I could not find out what the benefit of the CBP ones were, just an alternative I think. I have not had to remove them yet n mine, although it is planned on syncroswedes 2.1, that is after adjustment if it doesnt cure a slightly noisey action.

[dugcati]

Someone took em out on my van and put in solid lifers!

Which is better solid's or hydraulics?

[Laurie]

You have a performance cam too doug. Solids any day.

[Therunner]

Just out of interest, what would happen if say, the tappet from no. 3 inlet was missing all the little springs and ball bearings etc, just leaving the 3 larger parts? And more to the point, why would anyone put one back in minus these parts?

Melvin

[Laurie]

If they wound the tappet adjuster up to compensate, they might have done it, but I've yet to see one with those bits missing.

[Therunner]

oK, seemed an odd thing to do, but I suppose if it worked . . .
This was the only one that fell out when I removed the heads, barrells and pistons. For ages I assumed that they were all like that, until I looked more closely at the Haynes diagram and then removed the remaining 7

Thanks

Melvin

[jake1953]

Clacky lifters can also be attributed to a worn pressure relief valve, which is easy to replace, and also cures some buzzer of doom problems. A lazy spring reduces tick over pressure and prevents pressure build up in the lifters.

Where would I get hold of a new spring? need one soon

[syncrosimon]

Part 15

021115421B shown as available in europe. Check with VW van Centre. Just ring em up and ask for price and availablilty.

My limited understanding is that a weak one will cause low oil pressure across the board. This will not help you hydraulic adjusters, but it also wont cure a worn engine.

Good luck