has anyone had trouble with hyd lifter pump-up when the head has been cut(.075). i am trying to sort out a bad lifter noise( sounds like a diesel). the engine was torn down and cleaned-up after burning a ex valve from a pluged cat convertor. it has good flow to all rockers when running,push rod were soaked and blow out, oil pressure is 25lbs at idle hot.any thoughts?

Seems to me there was a thread on this recently.....Doug had some good info.

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Yeah....Im the one who destroyed this rare, vintage automobile.....

sandy i made .065ths shims for the rocker shaft to bring the preload back to stock. the lifer noise level is more even but still more than i think it should be. when i check rocker play it is very inconsistent, i not sure if the shims are too thick or too thin?

If oil is getting to & thru the pushrods (is the rocker shaft installed correct side up, & correct end forward?), then you either have springs that are too strong- causing lifter bleed down, or you might just have some bad-dirty-worn lifters. Most new hyd lifters for /6 have probably been on the shelf for a decade or two.

The /6 hyd setup is "clever" & worked with wimpy factory valve springs. If something caused too much lash, then you'd 'lose' most of the oil supply to that lifter, making the clatter worse (eventually it would fix itself-for a little while).

In general, for most hyd lifter setups - as long as the lifter plunger has some preload (say 0.030") but isn't bottomed out then it should work ok

Shimming the rocker shaft that much will alter rocker to valve tip geometry - you need to check it to find out if this was a good thing or a bad thing. Be careful with .065" shims, that's how I split a rocker shaft tower on my head (the shim should be thinner on the sides & thick on the bottom)

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63 Valiant Wagon
225 - 4 bbl

i did replace the stock spring with stock v8 ones they have no damper so the not to much of a step-up but it could be a thing to check. i did tapper the shims,i have reduced the shim to a .055ths it is better but as the engine slow it has a rattle,i don`t know how quite this engine was before i got it so if there was a lifter problem or not?

Even with oil getting to the rockers it has to come out to go threw the pushrod. I have seen the passage way stopped up in the rocker arm cause this. Also I think getting the shaft turned wrong could cause this. Being upside down or just truned 180 degree will do it if I am not misstaking.

Rockers with to much clearance on the shaft may also cause problems but I think they would pump up some even if this was so. It souonds like your getting no pump up at all so I expect what ever it is has a total lose of oil getting threw the pushrod.


It is possible that the angle of the pushrod to the rocker arm is so off that the hole in the end of the pushrod is not getting to line up with the oil feed in the rocker, Thus blocking flow.

Its been a long time sense I have even had my hands on a hydro setup and i cant remember what type ends they have, Ball & cup maybe? If new pushrods where used a mismatch in the size end can have a effect.



The most common problem I have seen was stopped up rocker arms. Many a factroy setup would qquit oiling and this would be the cause. Lifters being over come by spring pressure would take a lot to happen ( extra heavy springs). BUT, if the system was on the edge of being stopped up it could happen easy. IF it did turn out to be a spring thing and it is just because of to much pressure incressing the orfic size of the oil feed threw the rocker "Might" help. Tigher rocker to shaft clearance could also help ( have them bushed with bronze to tighten up).



Hope this helps, good luck.
Jess

i need to get the proper shim, the home made seem to be leaking around the rocker stand. i have one question, should i have some lash or clearence at the valve stem when the lifter a not pumped up before startup?

You shouldn't have any lash or clearance when the engine is off. The plungers are spring loaded and should be plenty strong enough to hold the pushrod up. I measured the plunger travel on a set of replacement hydraulic lifters and there is a bunch. I would try running the engine without the shims. If it doesn't miss when it's warmed up then it should be fine.

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Joshua

as doc has said in one of his other post`s ,there is only .060 travel in the lifter ,i dissasembled one and all that is in there is a cup shaped piston with a machined well under it to hold a small amount of oil. when there is no oil pressure i can`t these holding any load just bottoming out on the machined lip just below the piston in the lifter it self. that is why i asked if a small amount of lash should be at the valve stem before oil pressure come on?

I have a set of H2089 lifters in Clevite boxes. There is .190" of plunger travel in these lifters, but this may be different from stock. These lifters are new and I had to push the plunger down in order to measure the travel. Are you telling me your lifters are collapsed at rest?

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Joshua

yes, this is the first hyd cam engine i tried to modify, all others were mechanical, the lifter had only a piston inside and a well to hold the oil. i have a .020ths shim in there now it still seems the same so i am going to try it as is, see what happens

On every hyd lifter I've worked on, there's a snap ring/ wire clip, pushrod seat, piston/plunger, oil check valve, & a spring pushing everything up against the wire clip. If you take the valve cover off & push on the rocker arms as hard as you can (down on the pushrod side)- all should be "rock hard" & solid. If there's a gap or one feels soft, "bouncy", or goes down, then that lifter is probably dirty or no good - or is starved for oil. (if you ever took the lifters out, you did put then back on the same cam lobe? You can put a new lifter on a used cam, but a used lifter has to go back on it's "matched" cam lobe or it will wipe out)

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63 Valiant Wagon
225 - 4 bbl

will on these lifters the pushrod seat ,plunger and piston are all the same part, all i see is the snap ring is limiting travel.

You may want to try a different set of lifters...
Northern has some they are selling cheap, here is the ebay listing
ebay Lifter Set