5.0 gl valve lash adjustment

[mcurcio1989]

I will try to keep this as short as possible. I have a 5.0 gl volvo penta engine with an sx outdrive. We ran into a problem last years that necessitated pulling the heads off. So we did that and got everything back together and she seemed to be running alright out of the water. After we put it in the water it did not want to run and it was clear that something wasn't right. Ended up checking compression and found readings from 0-160psi. Every cylinder was different and all across the map. Before the work comp. was perfect. So I went through the procedure in the manual for setting valve lash. I got the #1 cylinder which had 0psi to go to 160. but none of the other ones want to go. So then I checked #6 which should be right because it was set at tdc and verified using the distributor. Well that was getting 30psi. Just out of curiosity I turned the nut on the exhasut valve and intake valve back 1/2 turn for the number 6 cylinder. Now it gets 150psi. So this verifies that the procedure is wrong. It tells me to go to when the push rod won't turn and then turn it 1 full turn in. That 1 full turn is what is doing it. So does anyone have an idea on what to do here? The manual says to go 1 turn in but that 1 turn is not allowing the valves to close.

 

[Monte1961]

Re: 5.0 gl valve lash adjustment

1st? is it a hydraulic cam and lifter setup or is it a solid lift cam and lifters? If hydraulic it's very easy to do but will be messy! Solid will be more complicated but less messy. Please post back and let us know. But with the year, I suspect it will be hydraulic.

 

[Don S]

Re: 5.0 gl valve lash adjustment

Every Volvo (and Mercruiser and OMC, etc.) has hydraulic valve lifters. It's a Chevy small block, they all are.

The lifters can be adjusted without the engine running. There are basically two major problems that happen with valve adjustments to newbe's of the job.
The first, is not having it on #1 TDC when starting. IF that happens the valves will all be out of adjustment and probably work just like yours does. The highlighted part in the first picture below explains how to verify if you are on #1 or #6 TDC.
The second thing usually done wrong is removing valve lash.
Here is how it explains it.
Turn the valve rocker arm nut clockwise until all the valve
lash is removed (zero valve lash). Zero valve lash can be felt
by moving the pushrod up and down between you thumb and
forefinger until there is no more up and down movement of
the pushrod.

To do this job properly. While moving the pushrod up and down and slowly tightening the rocker nut, the trick is to come down until the movement just stops. That's it, check it one time and one time only DO NOT re-check. If you wait a few seconds, it will be loose again, don't worry about it, you have done the initial lash removal, and no further checking is needed.
Now turn the nut down the additional turn and the adjustment on that valve is done. Time to move to the next.
I have done this hundreds of times and it always works. If there is a problem, one of the above items was done wrong.

 

[stant1man]

Re: 5.0 gl valve lash adjustment

How do you know which are the intake valves and which are the exhaust valves?

 

[Don S]

Re: 5.0 gl valve lash adjustment

Look at the intake ports on the intake manifold. They are above the intake valves. Same with the exhaust. The exhaust ports lead to the exhaust valve.