Oil Pump, internal

[Solo2882]

I have a very unique issue with my 1997 Sea-Doo GTX with a 787 engine. I believe the internal oil pump that circulates the two-stroke oil through the block is not working. After doing a full rebuild on this engine, I noticed that when the engine is cranking, I do not see oil circulating from the oil reservoir to the inlet of the engine and then back to the reservoir.
I even pulled off the oil return line to the reservoir and blew pressure into the reservoir, and oil bled out into a cup. But when I crank the engine over, there is no oil flow.
I also believe this may be part of the reason why I’m having a fuel delivery problem, because the components inside the engine block are not being lubricated properly.
What could be the issue? As I mentioned, the engine had a full rebuild, and the counterbalance has brand new seals.

 

[burtshaver2021]

Doesn’t work like that, the oil doesn’t circulate through the Rotary valve cavity, yes there is a supply line going from the bottom of the oil tank to the rotary valve under the intake and there is a return line going from the other side of the engine to the top of the oil tank but return line is probably the wrong name, call it rotary valve vent line, this line is really just for the expansion. This had nothing to do with a fuel delivery issue.

 

[Solo2882]

Doesn’t work like that, the oil doesn’t circulate through the Rotary valve cavity, yes there is a supply line going from the bottom of the oil tank to the rotary valve under the intake and there is a return line going from the other side of the engine to the top of the oil tank but return line is probably the wrong name, call it rotary valve vent line, this line is really just for the expansion. This had nothing to do with a fuel delivery issue.

Thank you, I appreciate the information. I had a very hard time trying to find this online. I never had a fuel delivery problem—I just had bad spark plugs, lol. I’m just curious if you or anyone else here would know whether an aftermarket paper fuel filter would be okay on these engines, or if it needs a high-flow plastic screen filter like the original.

 

[burtshaver2021]

Thank you, I appreciate the information. I had a very hard time trying to find this online. I never had a fuel delivery problem—I just had bad spark plugs, lol. I’m just curious if you or anyone else here would know whether an aftermarket paper fuel filter would be okay on these engines, or if it needs a high-flow plastic screen filter like the original.

Your welcome, big big no to the paper fuel filters, OEM is best as it acts as a water seperator as well, it’s basically just a fine mesh screen, should be able to pick one up used for next to nothing. If you can’t get a used one, I guess the next best thing would be a filter with a fine mesh screen