"D&LBusch" wrote in message
...
I have a Mercruiser 5.7 with 450 hours built in 1988. I'm about to lay it
up for the season (northeast). Does anyone have a suggestion for engine
oil? I'm inclined to use 10W30 Dino oil which is what I use in my car.
The boat is new to me so I don't have a "what did you use last year" to go
by. Any ideas would be appreciated? Thanks, David

You may want to consider allowing your local marina winterize your boat.
They will fog the engine, put stabilizer in the fuel tank, put oil in they
cylinders, pull the outdrive and grease everything and then drain and fill
all coolant passages with non-toxic antifreeze. It is a fairly major job
and since the boat is new to you it is a good time for the mechanic to check
out the lift system (top up the hydro oil), check out and grease the
universals and so on. You may also want to get the drive gear oil changed.
You can do this yourself at the same time you change the engine oil or let
the marina do it. It is a simple job.

To answer your question you should use 30wt oil. I would also tune it
(plugs, rotor, distributor and new fuel filter) before winterizing it. The
fuel filter looks like an oil filter usually mounted somewhere close to the
engine.

good luck,
mark