Hi,
Volvo penta D1-30. Idle- 3600 rpm no smoke. Under load start from 2400 after +- 1 hour max 2200 and white smoke from exhaust. Fuel humidity- no but looks like
.sometimes one time per hour rpm goes down suddenly without reason and then with knoking song within 10 sec co.e back to normal. While rpm down a log of white white smoke cominh from the exhaust. ...
Action taken:
1. Change fuel tank twice eith new diesel
2. All filters of fuel system chenged twice
3. Fuel injector Nozzle of cyl no 1 found completely clogged, after 40 min ultrasonic cleaning, unblocked. After 500 hours the story repeated but i do not believe that it is again nozzle.
5. Sump tank pressure is normal but increasing with time pass ( suspect piston rings ). Pipeline on dipstick was fitted with hose for this purpose. Looks like piston rings are ok.
6. Valve clearance checked, found ok.
7. Engine full service done ( oil, filters )
8. Fuel system servicec( all filters )
9. Fuel line was blown to the tank , clear.
10. Fuel cut off valve overhauled. No prob.
11. Exhaust mixer from engine cleaned ( minor deposits )
12. Exh line from engine blown to overboard ( clear )
Engine still working at ma 2400 ( hull has some minor seagrowth ) with white smoke from exhaust. Once per hour rpm dropped almost to idle or even stop showing a Lot oc white smoke then come back to 2200 withi 10 sec with minor white smoke.
What it can be