newbe with oil ?

[agray58]

Hi all, first post on this forum.
Easy questions for wiser boat motor heads!! I have a '79 21 foot Sleekcraft Daycruiser with a Ford 460 and Panther Jet. First oil change is due since I purchased the boat and I'm not sure what wieght oil I should run. Is 10w-30 O.K.?
Second question is, I run about 50mph at 4000rpm, does this seem right? Or should I be running higher in the rpms?
Any info would be great, if it helps I live in the Northwest near Portland Oregon and run the Columbia River mostly. Thanks.

[fourspeednup]

First off, welcome to our corner of cyberspace:cool:
Run straight 50wt oil
4000 at 50 sounds about right for a heavy boat

[agray58]

Thanks for the reply. Is straight 50w oil o.k. for start ups? I thought I would need a variable wieght so I have lubrication when it's cold, or is it different in marine applications?
I feel a little better about my rpm now, however are there things I can do to massage some more mph out of this boat or is my wieght to much of an issue?
Thanks again!!

[Moneypitt]

The only 50 wt you'll find is 50wt racing oil. It works better in a boat because of less detergent type ingredints, less foaming at high sustained RPM. If you're looking for better performance, just remember: $peed co$t money, how fast do you want to go.... And the more performance you get, the closer to the edge you are, and the edge falls off really fast. (breaks everything) If you're new to boating/ownership, leave it alone, enjoy the boat for what it is, a jet family fun boat. Then find and build a v drive for real speed. When the v drive breaks, you still have the jet for fun....Moneypitt

[Jet City]

I feel straight 40wt is the best choice for a stock or mild jetboat engine, I also run a mild 460/Panther in my boat, the sae 40 has served me well for many years. SAE 40 is readily available from Chevron, Valvoline, Pennsoil, Kendall and I'm sure a few more, most auto part stores will have it. As for the cold starts, I doubt you'll be using your boat when its cold enough for this to be much of a factor, if you feel you need a multi weight, an HDEO (heavy duty engine oil) such as 15w40 Chevron Delo 400 or Pennsoil Long Life would be a good choice IMO. I would also use a top quality filter (not Fram) such as Napa Gold, Wix, Baldwin.