I'm replacing valve springs and conponents on my 99 HP 500's and am getting conflicting answers. Mercruser says 1/2 turn and a respective offshore engine builder says 1 turn whom I also bought the parts from. Whats your opinion?

I have always gone with the 1/2 - 3/4 turn. But anywhere around that mark will work o.k.

Good question, I had several valves that would not quite down until 1 turn. After 50 hours of running I plan on going back and setting them at 5/8.
Tim T.

You will probably get several correct answer to this. I as did BadDog have a set of hyd roller lifters that would make noise unless set at 1 turn down. I have for years ran hyd lifters at 1/2 turn with no trouble. Crane said to run them at 1 turn. Check www.cranecams.com if you want and you will see they recommend 1/2 to 1 turn or .020 to .060 preload. Good thing about hyd is they are some what forgiving on adjustment.

Thanks for the replys I think I'll go 3/4 turn and be safe.