'97 Mariner 9.9 hp 4 stroke - low oil pressure

[muskyscratcher]

I have a 1997 9.9 HP 4 stroke. It's a Mariner/<br />Merc made by Yamaha, in its tenth season, used about 30 hours a season.<br />Bought this motor new. Never a problem. End of last season, oil pressure light went out, indicating low oil pressure. Motor won't run over<br />2,000 RPM per owners manual. Oil level checked<br />out fine. Changed oil filter and found rubber<br />oil ring sucked off filter and laying in motor<br />housing. Lucky I spotted it. Changed oil and filter. Still indicates low pressure.<br /> Should I expect to replace oil pump in tenth season??? Also, I have always used 10w30 Mobil<br />One Synthetic. Could that be a problem?????<br />Does a 9.9 HP 4 stroke even have an oil pump?

 

[muskyscratcher]

Re: '97 Mariner 9.9 hp 4 stroke - low oil pressure

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[muskyscratcher]

Re: '97 Mariner 9.9 hp 4 stroke - low oil pressure

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[muskyscratcher]

Re: '97 Mariner 9.9 hp 4 stroke - low oil pressure

Found out a couple things<br />The 9.9 I have is the smaller CC, of the two types made in '97, think it's 209, definitely<br />not the 323CC. (Has a very small oil filter)<br />I need to find out if oil pressure is low<br />mechanically, to verify if possibly a pressure<br />sensor problem. Electronically the motor will<br />not exceed 2000 RPM. How can I get oil pressure<br />tested mechanically? Is there anyway to diagnose without breaking down block???

 

[muskyscratcher]

Re: '97 Mariner 9.9 hp 4 stroke - low oil pressure

Took 9.9 to the shop, still would<br />like any feedback. The Merc machanic<br />and I are worried that problem could<br />be trouble finding exact cause/diagnosis.