On Mon, 05 Jun 2006 20:39:54 -0400, Big gus
wrote:

WOW what a discussion.

after reading all the posts I guess I should clarify my question

The engines a 502 Merc inboards, not V-drives

I was wondering if anyone had been uses something like Valvoline 50
weight racing oil.

When I switched my Crusader 454's from the 25W-40 marine oil to
Valvoline 60 weight, per advice of a 30 year marine mechanic, the boat
ran 100% better.

Now I have newer boat with engines that were rebuilt in 94, I am
trying Valvoline strait weight 50 racing oil.

I boat in Cleveland ohio on lake erie.

I WILL not "winterize" the boat with that oil, but its full blown
summer here and I just changed the "winterized" oil with the strait
weight Valvoline.

Thanks for all the advice



I'd be leary of using oil that thick.
Great for racers who pre-heat the oil to operating temp before
starting the engine. Not so great for cold-start conditions.

At one time I used 50w oil in my 4-cyl Isuzu PUP but I was crawling at
5 MPH through the Mojave desert for weeks at a time with no wind
through the radiator.

You might look at rebuilding your engine if it takes 50w or 60w oil to
make it run well.

Mark E. Williams