Originally Posted by casual
I am purchasing
a new used boat
.The yard where the boat is at only uses synthetic oil,The engin is a Yanmar 4JH3E appx 3000 hours,I have no knowledge of PO oil type,Will synthetic oil do is it better than Castro GTX which I have always used in my present Boat?I am sure I could get some Castro oil somehow.This engin was making oil due to a bad lift
pump,had oil analysis done all ok.Thanks for the help,PS this will be the first change after analysis
I'm convinced that synthetics are better oils for two reasons :
1) They retain their viscosity for longer (more use that is, not time)
2) They hold their viscosity over a wider range of temps.
However I don't think either of these are of much benefit in a sailboat diesel
, when the oil will probably be changed for time-expiry and not hours operation.
They make the most financial sense when you can take advantage of the longer life.
I suspect that ANY 15w/40 with a diesel
rating will do fine. I used Shell Rotella which is very popular with truck fleets. It comes in normal, semi-synthetic, or full. It's also available at Wal-mart quite cheaply and comes in 1 gal bottles instead of those stupid 1 quart ones so you've got something to pour the used oil into!