88 Yamaha 90 HP Oil Inj. leaking into cylinders when not running

[herndo1]

I'm' finding Oil that has leaked onto the ground below lower unit, that appears to have come from exhaust port around prop, which there is oil dripping from the skeg on the lower unit. I was told that the internal check valve within my oil pump is letting oil pass thru into my cylinders and then out the exhaust port. When I first start the engine after sitting for several days there is massive smoke but finally clears and everything seems OK. I had some inline Yamaha check valves installed in the oil injection lines that run to the carbs. Thought everything was OK but found more oil on the ground today.

Please Help
Thanks in advance
Adrien

 

[rodbolt]

Re: 88 Yamaha 90 HP Oil Inj. leaking into cylinders when not running

could be a check valve if you have the old style kein pump with the checkvalves in the pump, could be the oil pump shaft seal leaking. if its the check valve either buy the mikuni pump kit or try to splice in the later style inline check valves, make sure you do all 3 lines. I would prefer you replaced the pump.but it may be as simple as the oil seal.

 

[herndo1]

Re: 88 Yamaha 90 HP Oil Inj. leaking into cylinders when not running

[quote time1151632410= userrodbolt= uid32169= fid30= tid= rid1= could be a check valve if you have the old style kein pump with the checkvalves in the pump, could be the oil pump shaft seal leaking. if its the check valve either buy the mikuni pump kit or try to splice in the later style inline check valves, make sure you do all 3 lines. I would prefer you replaced the pumpbut. it may be as simple as the oil seal.
[/quote]
Im

I'm pretty sure I have the old style pump. I did install the later style inline check valves and installed them on all three lines. If it's the oil seal is there any way for this leaking oil to make cylinders' way into the cyliners?
herndo1
Thanks for the reply
herndo1

 

[herndo1]

Re: 88 Yamaha 90 HP Oil Inj. leaking into cylinders when not running

[quote time1151632410= userrodbolt= uid32169= fid30= tid= rid1= could be a check valve if you have the old style kein pump with the checkvalves in the pump, could be the oil pump shaft seal leaking. if its the check valve either buy the mikuni pump kit or try to splice in the later style inline check valves, make sure you do all 3 lines. I would prefer you replaced the pumpbut. it may be as simple as the oil seal.

Im

I'm pretty sure I have the old style pump. I did inline the later style inline check valves installed on all three lines. If it's the oil seal is there any way for this leaking oil to make cylinders' way into the cyliners?
herndo1
Thanks for the reply
herndo1
[/quote]

 

[rodbolt]

Re: 88 Yamaha 90 HP Oil Inj. leaking into cylinders when not running

yep, it will normally flood the bottom cyl. aint but two ways oil can enter the engine, either through the lines into the reed cage area or past the drive shaft seal into the lower cylinders crankcase area.