3.0 Rocker Arm Install

[9533Zero]

Reinstalling the rocker arms on my 3.0 mercruiser after having the head reconditioned and I'm confused on the torque settings. The manual says to torque them to 20 ftlbs but they don't get near 20 until they bottom out on the stud. Is that what I should be doing, cranking them all the way down to the bottom of the stud and then torquing to 20? Thanks!

Steve

 

[Bondo]

Re: 3.0 Rocker Arm Install

Ayuh,...

You have to do Each cylinder at TDC....

 

[9533Zero]

Re: 3.0 Rocker Arm Install

Doh! I feel stupid. Thanks!

 

[Don S]

Re: 3.0 Rocker Arm Install

You don't torque a 3.0L you adjust them. Only the later model 4.3 V6 used the 20lb torque

Head up to the Adults Only thread and download a manual for your engine, look at section 3 for details on adjustment.

 

[9533Zero]

Re: 3.0 Rocker Arm Install

Actually Don, thats what confused me. I have the manual and it does say when installing the rocker arm nuts to torque them to 20ftlbs and that no valve adjustment is required. Then it covers valve adjustment on the very next page. So, I guess I'm still confused. should I set each rocker to 20 ftlbs at TDC and then do the adjustment? Thanks again guys!

Steve

 

[a70eliminator]

Re: 3.0 Rocker Arm Install

Typicaly you either have an adjustable valve with all threaded rocker studs and either locking nuts or jamb nuts, or you have a non adjustable valvetrain that has either a threaded rocker stud with a shoulder for the nut to bottom (positive stop) on some engines the non adjustables are held down with a bolt. If you don't know which you have be safe and do as bondo says find TDC compression stroke and see if the nut bottoms out before the valves start to open, if you do it wrong you'll end up with a bunch of bent pushrods.

 

[Don S]

Re: 3.0 Rocker Arm Install

Actually Don, thats what confused me. I have the manual and it does say when installing the rocker arm nuts to torque them to 20ftlbs and that no valve adjustment is required. Then it covers valve adjustment on the very next page. So, I guess I'm still confused. should I set each rocker to 20 ftlbs at TDC and then do the adjustment? Thanks again guys!

Steve

What manual are you looking at?

 

[Chris Hays]

Re: 3.0 Rocker Arm Install

NOOOO!! You must have the same stupid book as me (SELOC) I went to start turning them to 20ftlbs and being experienced figured out quick its not right. If you do this you will completely compress the lifter, AND the valve will be open even at TDC!!!! Set the engine to TDC then take the slack out of the push rod with the adjusting nut, thats all you need to do.

 

[9533Zero]

Re: 3.0 Rocker Arm Install

Got it. Thanks to all!

Steve