Mercruiser 302ci ford? Oil & sludge of the 1970s

[Fordiesel69]

I am looking at a 1973 boat with a 302ci ford/merc i/o. Of course oils of the 70's produced soem nasty sludge and varnish inside many engines. Is this going to be a problem today with this boat from all the years of that [censored]? I would be using SAE 30 or 40 pennzoil in it.

Reason I mention this is many older 70's ford inline six engines and v8's that either I or friends have owned all have main bearing rattle and low oil psi. I wonder if this will be the case with the boat.

 

[Rob_Roy]

Do you know many hours are on the engine? Most non-commercial marine engines don't get a lot of hours annually, if the oil was changed once per season it shouldn't be problem. A few quick oil & filter changes will help with the cleanup.

Something else to watch for is corrosion issues, especially if the engine has seen any salt water.

 

[Fordiesel69]

The guy that owns it now takes care of stuff to the third degree, and no it was only used in lake erie and surrouding areas.

Was the 302 a good marine motor?

 

[BUBBA0420]

The 302 was a pretty good marine engine. Do a compression
check to know the condition. I would also me concerned about
the condition of the boat. You don't say what the boat is.
At that age make sure the stringers and the transom are free
of rot. Also was the outdrive or engine ever rebuilt ??