what's the correct valve lash procedure?

[scottishgold]

Hi there, <br /><br />Can anyone give me some advise on how to expertly do the valve clearance on the mercruiser 120, 153ci chevy? The SELOC manual says start with cyl 1 at TDC then gives you the valves to adjust, but I read some guys just do TDC for each cylinder and adjust those valves? Is there a correct procedure and what is it?<br /><br />When you are feeling the play on the push rod, do you twist it gently or move it side to side?<br /><br />Cheers

 

[calwldlif]

Re: what's the correct valve lash procedure?

The manuel procedure is less<br />turning of the crank. it uses "Marks"<br />on the damper not "approx" places, like<br />when you try to get TDC for each indiv<br />cyl. To get the lash on hydrolic when not<br />running...gently twist, spin, rod while<br />tightening rocker untill you feel 0 gap.<br />It is hard to write what that feels like,<br />to me when barely turning rod I can "feel"<br />when the rod justs starts to seat in rocker,<br />rod stops turning with the gentle force I am<br />applying.

 

[Mile-High Mariner]

Re: what's the correct valve lash procedure?

Scottishgold - WildLife neglected to mention that, when adjusting valves using hydraulic lifters, you need to adjust to zero lash, then an ADDITIONAL 1/2 to 3/4 to 1 full turn past zero - your manual will tell you which (1/2, 3/4 or 1 full turn past zero). Or ask Don S - he'll know for sure if you identify the year, model and serial number of your engine.