valve lash, 4.3

[Rbryan94]

OK I'm a little confused and need some clarity. I hope someone can clear things up. I had a bad riser that leaked antifreeze into #2 cylinder. Ended up bending a couple pushrods and wrecking some valves due to hydro lock, had the heads tested new valves installed and I'm ready to reinstall. It's on a 1988 4.3 mercruiser 175 HP roller lifters ,thunderbolt ignition with carb. Ithe motors are so close together I can't get to the ser# by the starter. My question is how to adjust valve lash. I get TDC and when to adjust intake and exhaust valves. One book says one full turn another says three quarters after lash has been removed. I'm old school and used to soak lifters in oil to prime. The machine shop says no more. Just pour oil on them and stick em in. He also said tighten until push rod just meets lifter (still can turn pushrod) then go half turn ! Any help would be appreciated.

 

[alldodge]

Re: valve lash, 4.3

OK I'm a little confused and need some clarity. I hope someone can clear things up. I had a bad riser that leaked antifreeze into #2 cylinder. Ended up bending a couple pushrods and wrecking some valves due to hydro lock, had the heads tested new valves installed and I'm ready to reinstall. It's on a 1988 4.3 mercruiser 175 HP roller lifters ,thunderbolt ignition with carb. Ithe motors are so close together I can't get to the ser# by the starter. My question is how to adjust valve lash. I get TDC and when to adjust intake and exhaust valves. One book says one full turn another says three quarters after lash has been removed. I'm old school and used to soak lifters in oil to prime. The machine shop says no more. Just pour oil on them and stick em in. He also said tighten until push rod just meets lifter (still can turn pushrod) then go half turn ! Any help would be appreciated.

According to manual No 7 you turn the nit down until the push rod cannot be turned by you fingers, then turn an additional 1 turn.

 

[Rbryan94]

Re: valve lash, 4.3

Wow ! That seems a bit much but maybe that's how it has to be done. Thank you for the response

 

[MikDee]

Re: valve lash, 4.3

I always set them at 1/2 a turn down from that point.

 

[Rbryan94]

Re: valve lash, 4.3

Thanks, maybe I need to adjust them running. I read service manual #7 and it doesn't say anything about not being able to spin the pushrod when removing lash. It says to remove the up and down play then tighten one full turn. That sounds a little better. Anyone else want to chime in on priming them before they go in.

 

[Idlespeedonly]

Re: valve lash, 4.3

Turning till the up and down play and till they stop spinning is basically the same result you are looking for. I have always turned 3/4 turn after zero lash. but 1/2, 3/4 or even 1 full turn will more than likely be fine.

 

[Watermann]

Re: valve lash, 4.3

Man I always have put new dry lifters in a can of oil and used a pushrod to pump em full up. Not much 'nowadays' in a 26 year old motor and it's parts.

 

[cr2k]

Re: valve lash, 4.3

I am old school too. On my stuff I go 1/2 turn. On customer stuff I go the full turn on the newer stuff and 3/4 on the older stuff like 120s and inline 6s. But hey, that's me. I have always either pumped them up in a can of ATF or let them soak overnite to fill. But they will fill up when running, although they may rattle a little at first, so no revving until warm up is complete.