90 hp 2 cyc year 2000 oil injection maintenance

[wn6ngp]

I've got a 2000 model built in '99 90 hp 2 cycle, s/n 0T08766 about 300hrs 3/4 time fresh and 1/4 salt.. Its been a great motor.but its getting old. I did some reading about possible failure of the oil injection pump. The few posts I've found seem to refer to other mercs regarding plastic gears and a major job to replace the pump. Looking at my official service manual it seems like it would be an easy thing to remove and replace if necessary. Its bolted onto the block just under the fuel pump.

What are the opinions on whether I should replace it? I don't hear stories of failures of the pump on motors like this so I'm tempted to leave well enough alone. Does this model have plastic gears on the oil pump and is it as simple to remove and replace as it appears.

tks
don

 

[racerone]

Well, ---The plastic gear fits on / around the CRANKSHAFT.----------You have to tear the motor all apart to replace that gear.---------The one that goes into the side of the block is steel !

 

[wn6ngp]

Ughhh....that explains it. I guess I'll keep on truckin with it as is. Seems like a better design would have been to have metal gear on crank and plastic on the pump shaft. I am probably missing something.

I don't want to go pre-mix since I drain the fuel off the tank after it gets about 6 months old and doesn't get used. I burn that in the car so premix would eliminate that option.