Diana 1991

I will be crossing the tidal ribble this summer. The engine will be out of its usual 1200rpm comfort zone for a few hours and I am concerned that this may reveal issues. What are the maintenence issues I should be paying particular attention to? How high will I need to rev the engine during the crossing? It is a Perkins MC42, PRM 150 gearbox, boat length 57 foot, not sure what the propeller is. The engine produces smoke at about 1800rpm. I intend to use 20W50 oil to hopefully reduce this smoke then replace with 15W40 for the winter. As always thanks for any advice.

I want to do my first DIY oil change and thought it would be straight forward. The more I delve into filters & oils the more complicated things get. My engine: Perkins Agricultural engine 104-19 marinised by Duffield Marine. Engine number KF 30264 J 03623 S. Diperk have identified the oil filter part number as 140516130 which is the Perkins part number I believe. They have a minimum order charge of £15 which I would rather avoid. The filter fitted at the moment is a Crosland 529/1 but I do not know if this is a suitable alternative to the original filter. Which oil filter do those of you who have this engine fit? On the subject of oil I have identified that I need ideally 15W40 to API CC. However there are two 5L cans of new oil on the boat which I would like to use up, Castrol GTD Plus 10W40 API CF and Granville 20W50 Premium (no API spec). I am inclined to use the Castrol in this oil change topped up with the Granville and use the Granville up in the PRM gearbox. Any Thoughts? Any advice particularly on oil filter greatly appreciated. John.