setting adjusting valve lash after a re seal
Thread Starter
Oil Producer
Joined: Apr 2014
Posts: 9,377
Likes: 2,737
setting adjusting valve lash after a re seal
Question.
Currently tearing down an engine, to get the heads inspected, do a valve grind, vss, and reseal etc.
When i get to the valve lash…
Can i run my old distributor that i made into an oil pump primer….to pump ip the system so that oil is coming out of all the pushrods….and then do this:
(my question is really should i pressurize the system with my dizzy turned oil pump primer)
method i use, from @Joe C
for the adjusting sequence and method, follow the FSM - that basic method's been working since 1955, and widely used at the factory during the engines initial assembly. as follows --
with the engine in the #1 TDC (compression), adjust the following:
exhaust -- 1, 3, 4, 8
intake -- 1, 2, 5, 7
(this is my personal method) instead of "rotate the push rod while turning the adjusting nut," I use a .0015" feeler gauge, between the rocker arm and valve stem, slowly tighten the adjusting nut until the feeler gauge "grabs." [i add oil to the feeler gauge so i can really feel the “grab”] at that point, you should be within .001" of zero lash. then adjust the nut 3/4 turn. this method seems a little more exact or precise than the "rotate the push rod" method, which IMO is a little too subjective. this should result in a more even adjustment across the board. either method will, however, work just fine.
now, rotate the crank 1 revolution or 360° and adjust the following:
exhaust -- 2, 5, 6, 7
intake -- 3, 4, 6, 8
Currently tearing down an engine, to get the heads inspected, do a valve grind, vss, and reseal etc.
When i get to the valve lash…
Can i run my old distributor that i made into an oil pump primer….to pump ip the system so that oil is coming out of all the pushrods….and then do this:
(my question is really should i pressurize the system with my dizzy turned oil pump primer)
method i use, from @Joe C
for the adjusting sequence and method, follow the FSM - that basic method's been working since 1955, and widely used at the factory during the engines initial assembly. as follows --
with the engine in the #1 TDC (compression), adjust the following:
exhaust -- 1, 3, 4, 8
intake -- 1, 2, 5, 7
(this is my personal method) instead of "rotate the push rod while turning the adjusting nut," I use a .0015" feeler gauge, between the rocker arm and valve stem, slowly tighten the adjusting nut until the feeler gauge "grabs." [i add oil to the feeler gauge so i can really feel the “grab”] at that point, you should be within .001" of zero lash. then adjust the nut 3/4 turn. this method seems a little more exact or precise than the "rotate the push rod" method, which IMO is a little too subjective. this should result in a more even adjustment across the board. either method will, however, work just fine.
now, rotate the crank 1 revolution or 360° and adjust the following:
exhaust -- 2, 5, 6, 7
intake -- 3, 4, 6, 8
Race Director
Joined: Aug 2000
Posts: 11,470
Likes: 764
-- glad to see someone is making good out of my technique. nothing special as it was pure desperation one day when i continually kept getting #1 intake too tight. can't remember when i started it, but I'm thinking it's been some 20 years now.
Le Mans Master
Joined: Aug 2017
Posts: 6,943
Likes: 1,490
From: New Jersey
I've done them in a similar manner... you do have quite a bit of wiggle room on the lifter preload... it'll run fine with a quarter or even a little over 1 turn of preload in most cases. I just lift up and down on the pushrod until I don't feel it moving then set preload. Feeler gauge is a little more precise. I've gone back and checked running and they're all usually dead on.
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Thread Starter
Oil Producer
Joined: Apr 2014
Posts: 9,377
Likes: 2,737
I've done them in a similar manner... you do have quite a bit of wiggle room on the lifter preload... it'll run fine with a quarter or even a little over 1 turn of preload in most cases. I just lift up and down on the pushrod until I don't feel it moving then set preload. Feeler gauge is a little more precise. I've gone back and checked running and they're all usually dead on.
Thanks all!