Did a compression test and Cyl #6 had 0, #4 was 135. Pulled the valve cover to find #6 stuck open. Pulled the ehuast manifold to look inside with a flashlight- #6 was of couse open and #4 didn't appear to be seating very well. With a piece of wood and a hammer I tapped the valve on #6 and it did come back up. Ran a couple of compression test and got different readings between 135-150. Took the head off and brought it to a local machine shop. I am waiting to hear something next week, but, hopefully the propblems found. I read an article on burnt sticking valves and it sounds about right.

There was a bent valve on #6 exhaust, so that was replaced and they re cut valve seats on all. When reinstalling the head there was a small mark on the top of piston #6 where the valve touched- didn't look bad.

When adjusting the valves I am following the Merc manual which tells me to bring it to TDC on #1 and set certain intake/exhaust valves. Then rotate 360 and then set the remaining valves- so two positions on the crank set all of the valves. With the crank at position 2 ( 360 from TDC #1) it should be TDC #6 , but when I adjust this valve the exhaust valve creaks slightly open... is this the sign of something off? I hear of posts where people question the timing chain... is the crank and cam being "off" the Hallmark of this?

Sorry to hear of your problems.

This is the easiest way I have found to adjust valves:

When adjusting the exhaust valves watch the intake valve for that cylinder while rotating the crankshaft. When the intake valve is closing about mid stroke (intake valve going up) the exhaust valve is fully closed and can be adjusted.

When adjusting the intake valve watch the corresponding exhaust valve while rotating the crankshaft. When the exhaust valve is opening (exhaust valve going down) you can adjust the intake valve.

I just remember 'intake up' and 'exhaust down'.

4mula,

Ran it this morning with the valve cover off and noticed that only a few of the push rods had oil coming up. It was idling poorly, but I ran it for around ten minutes , but the majority of the push rods still had no oil coming up. If I understand correctly there should be a little "pop" of oil coming up from the top of each push rod and running on the top of the rocker. I took the intake manifold off and took the lifters out. I took one apart and found some bits of metal - but not much. The oil in the lifter looked old- like it wasn't cycling oil through it. Dose any one out there know if the lifter should be "pumping" oil?? When putting it back together( the lifter) should it be filled with oil or left dry?

Any good Mercrusier mechanic want a free vacation to the Bahamas??? I'm serious.

4mula,

That sounds like a good way- it makes sence anyway. So basically adjust each one when it's fully closed.