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After a break from playing with cars for twenty something years, I'm back and apparently some of the basics escape me.

I have a BB Chevy 540 with a hydraulic roller cam. Motor is fairly fresh and I've found some things on the build that needed attention so I'm going over everything I can think of, including valve adjustment.

All of my drag motors had solid rollers and it's been a long time since I messed with hydraulics.

When adjusting the valves, if you tighten the rockers to zero lash and then go another 1/4 to 1/2 turn, I can see the valve just coming off the seat. Please help me understand how the valve is going to fully close. Keep in mind this is a motor with some use so the lifters are fully "oiled up".
 

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The lifters need a little time to bleed down.

On hot rod/ competition engines I like to do a final adjustment with the engine running, I typically do hydraulics 1/8 to 1/4 turn past just quiet. The engine will probably stagger as each is adjusted till the lifter bleeds to where it isn’t holding the valve open. Slow and easy is the word if it does this, give it time to settle down before pushing the adjustment further. Essentially the adjustment is forcing the pumped-up condition from which the lifter needs time to bleed off.

Bogie
 

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If you place your finger on the rocker you will feel or you can use a use a caliper to see when the rocker starts to drop.

Mark the spot on the socket then turn the crank over 1 full turn which puts the cam 180 and pushrod at the bottom.

Then you can turn the bolt while spinning the pushrod till it does not spin any more.

Move onto the next rocker turning that engine over as you go and checking your previous pushrods for spinning.

The order does not matter. I run 13572468 on a v8. Once all the pushrods are tight and have no lash you can go through and turn all the bolts 3/4 turn without needing to turn the engine over and your good to go.

Just dont make the mistake I did last week and assume you have hydraulic lifters. Breaking off a bolt in the process. It was not a hard thing to fix. The old bolt came out using just the left handed drill bit. But lesson learned. I have a bit of ticking still and will try some rislone while I consider going hydraulic or just a engine swap.
 

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If you place your finger on the rocker you will feel or you can use a use a caliper to see when the rocker starts to drop.

Mark the spot on the socket then turn the crank over 1 full turn which puts the cam 180 and pushrod at the bottom.

Then you can turn the bolt while spinning the pushrod till it does not spin any more.

Move onto the next rocker turning that engine over as you go and checking your previous pushrods for spinning.

The order does not matter. I run 13572468 on a v8. Once all the pushrods are tight and have no lash you can go through and turn all the bolts 3/4 turn without needing to turn the engine over and your good to go.

Just dont make the mistake I did last week and assume you have hydraulic lifters. Breaking off a bolt in the process. It was not a hard thing to fix. The old bolt came out using just the left handed drill bit. But lesson learned. I have a bit of ticking still and will try some rislone while I consider going hydraulic or just a engine swap.
I would assume that a non hydraulic , ( solid) lifter cam , would tick ?
 

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Hyd lifters are a pain sometimes. Try wiggling the push rod up and down instead of spinning it. It’ll give a better feel for 0 lash. Especially on the stock type rockers and nuts as the cramped threads create so much resistance finding the sweet spot is harder.
Something else you can do, is use a .020 feeler guage and set lash like a solid roller. Then tighten the nut 1 full turn. On 7/16 stud, 1 full turn will take up the .020 plus another .030 and put you in the middle of the lifter plunger travel.
The feeler guage gives a better feel for lash if the intake is on and the pushrods are harder to access.
If you have poly locks, tighten the nuts with your fingers only, no tools, and 0 is easy to feel.
I like doing valves in the firing order and turning the crank 90’. It’s a bit more idiot proof and I need that in my life
 

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When I set lash on my hydraulic lifters on my 350 I use the firing order method and it serves me just fine for the last ten years since I learned to set valve lash on those. With full roller rocker arms its a lot easier for me to adjust them vs stock stamped rocker arms as the full roller has a different feel to it vs a stock stamped rocker arm for me at least but still doable after you have done it enough to where its easy to know you got zero lash.

I start by having it on number one cylinder firing stroke and I will proceed to lift the pushrod up and down and not the spin method as it can give you false feel at times. While I lift the pushrod up and down I also lift the tip of the rocker arm across the valve stem tip up and down as well and go back and forth and slowly tighten the rocker arm nut or polylock depending on what style your using and tighten until I can no longer lift the rocker arm tip off the valve stem and also no longer move my pushrod up or down. I will then back off the nut and loosen it up just a hair and re verify a few times to make sure I am at zero lash and then go past to where the lifter maker recommends to have them set.

I am running a set of Morel hydraulic roller lifters and I set mine at 1/2 a turn plus a 1/8 more after locking down my polylocks. I adjust both valves then I turn my engine over a 1/4 of a turn and then go to cylinder number 8 and set it the same way. There are several methods to setting them and some swear one is better then the other and I won't argue on what is the best method as the firing order method has always worked for me on street performance camshafts with .550 lift and below with no issues.
 
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