valve/rocker arm adjustment

[Anonymous]

thanks very much to all those who have been helping me through my engine struggles...... you may remember my posts trying to determine why my exh. manifold was running unusually hot. Ended up pulling the head, and it looked like the intakes were not seating correctly. So a valve job later, I'm up and running now with the addition of an adjustable rocker arm assmbly. Another friend suggested I adjust the valves beginning with zero lash, then with the engine running, back off the adj screws until the valve makes noise, the tighten 3/4 turn. This was quite exciting.... never had the valve cover off with the engine running. My hands got quite a workout trying to hold onto those moving adjustment screws. I've also heard of a go-no go gauge.... thought I'd enquire as to people's prefered methods... thanks..... David SoCal

 

[pedal2themetal45]

I perfer the EO IC method (EO= exhaust open... IC= Intake closes)
start wit #1 Rotate motor by hand just as the Exhaust valve starts to open STOP and adjust the intake valve of that cyl. 1/2 turn past 0 lash.
Then rotate motor by hand watching the intake valve open then just as it starts to close STOP and adjust the exhaust valve of that cyl. 1/2 turn past 0 lash.

Tim

 

[rbohm]

8) it depends on the engine i am working on as to what procedure i use to adjust the valves. on engines with hydraulic lifters and stud mounted adjustable rocker arms, i like to adjust the valves with the engine running by backing off the adjusting nut until the rocker arm clatters, then back down until it stops, then a 1/2 turn more.

with non adjustable rocker arms, is use factory torque specs.

with solid lifters or shaft mounted rocker arms(llike on our small sixes) i warm the engine to operating temp, then adjust the valves on ech cylinder individually by starting with cylinder #1 at top dead center on the compression stroke. for hydraulic lifters use zero lash then 1/2 turn more. you can determine zero lash by moving the push rod in the vertical plane until you get no movement. for solid lifters i use a go/no go gauge to set the lash.

a go/no go gauge is just a feeler gauge that has been ground to the proper thickness for the go part, then slightly thicker for the "no go" part. you set the lash on the go part, and try to push the feeler gauge through the gap with the no go part. if you can get the no go part through the lash gap, then you need to tighten the lash until it wont go.

 

[Anonymous]

thanks folks,,, looks like I'm on track... David SoCal

 

[Bort62]

If you managed to adjust the valve lash while the engine was running, I am impressed. I tried to do so on mine and the damn rocker kept kicking the ratched off the nut.

Much easier on stud mounted rockers, I have to say.

 

[Anonymous]

I found the only thing that will work, although it is not fun, is the round fully enclosed end of a wrench, one hand to torque, the other thumb holding the wrench on the adj nut (with leather gloves to dull the vibration)... The first time I put a socket on it was at about 2am (trying to get the engine going for our local econo-meet at the rose bowl) and I thought I was in the Twilight Zone and cruel entity was playing a terrible trick on me.