mercruiser 120 valve adjusting

[jayandzach018]

hi first of all i just want to tell evryone THANK YOU for all the help you gived me and other people.... ok i had this problem befor and i adjusted the valves. The motor works fine will kinda fine but i think the valves is still off a bit and yes i did download the book and i was reading it like 10 times front to back and back to front but i still cant get it. what does lash in valves mean?

 

[havasuboatman]

Re: mercruiser 120 valve adjusting

Valve lash is the amount of a gap between the rocker arm and the top of the valve stem. You measure this with feeler gauge. Use the specs in the book you've downloaded. And remember that if the book tells you to do the measurement on a cold engine, that means sat over night cold. NOT one that has cooled for several hours.

 

[jayandzach018]

Re: mercruiser 120 valve adjusting

people say you cant adjust the valves with a feeler gauge? if you can can you help me with the specs???

 

[Don S]

Re: mercruiser 120 valve adjusting

If you have read the OEM manual, (as you say you have), and you can't understand the two different methods of adjusting that are given, then you need to take it to a qualified tech for adjustment.
There is no "Valve Lash" adjustments on a 120, they are hydraulic lifters and have no lash.

 

[fishrdan]

Re: mercruiser 120 valve adjusting

As DonS said, there is no valve lash adjustment, but you need to know when you get to "zero lash", the point where there is no free play between the rocker arm, push rod and lifter. Then set the preload.

Check out this youtube video, it will help fill in the gaps where you are not understanding the manual,,, but still use the Mercruiser manual's procedure.

http://www.youtube.com/watch?v=89o5rLpbCgI&feature=related