ShopTalk Forums | Aircooled VW Tech & Restoration Help

What is the adjustment procedure when setting up a hydraulic valve engine? What about ignition timing? What should line up with what, when?

John

All of those questions can be answered by any competent service manual. You don't mention your car, but if it's a Bus, check out the service manual from Bentley Pusblishing. I'm assuming it's a Bus engine, as the 914 and the 411/412 never came with hydraulic lifter.

Tuna

I asked WEB Cams directly and the answer was 1/2 to 3/4 turn in after contact. The procedure for adjusting can be found in any air cooled manual just instead of setting a clearence of .06mm you turn in the screws until they touch and go 1/2 to 3/4 turn in from there. I personnaly run 1/2 turn in on my 914 with a hydro web 73. Enjoy and I hope the lifter grim reaper does not knock on your door. (or mine)

1) Run the engine at .006" lash to get the lifters to "pump up" with oil.

2) Shut it off after about 10-15 minutes running.

3) Bring each cylinder up to TDC and set the adjusters to 1/2 - 3/4 turn past contact.

This has solved more noisey lifter problems in Hydro bus engines than I care to recall. It bleeds off any air pockets and helps get the pistons free'd up inside the lifters.
-Bobby

Thanks guys. Tuna, I already have a 914 manual it just doesn't have the hydraulic valve procedure in it or the timing procedure due to the different fan and shroud. This is an 82 bus engine. I don't want to buy another manual for just those two things. The rest of the manual wouldn't do me any good as this engine is in a dune buggy.

John

Do a search on the forums - this was beaten up pretty good a while back, and the consensus was that the adjustment procedure in the manuals is wrong. The factory adjustment was leading to valves being held open.

There are also some good posts on prepping and priming hydro lifters.

Search is your friend.

My factory (Bentley) manual says two turns past contact. This is the same as for a waterboxer. I assume that it is correct, but I have never actually adjusted a 2.0 aircooled. What I have found on waterboxers is that it is hard to feel the contact if the lifters are not fully pumped up. We're talking about only a few inch/pounds of torque on the screw so it is easy to miss the contact, and turn them in too far. I normally test for contact a couple of times just to be sure before giving the screws the final two turns.

There is a line of thinking which clearly says the Bently manuel is just wrong on this one subject.Two full turns is way too much and will cause the lifter too not pump up to it's full capacity.The 1/2 -3/4 turn method after the lifter has pumped up is the alturnative method.

on a new motor i start out at zero lash. you can feel it if you just use your fingers . run it like bobby says then half to 3 quarter turn. i have never found the need to do anything more elaborate.

What he said.