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I had my Yamaha rebuilt last year over the winter. I had a great year of trouble free use. A new water pump was also installed. The issue I am having is the motor starts and runs fine but I had much lower water pump pressure. It usually pumps hard after 5-10 seconds but not this year, motor was winterized properly. I also have which I think is two stroke oil lightly coming out dripping down from the midsection of the motor. I think this is where the internal muffler is ?I also thought I may not have the ears on correctly so I found a large garbage can to run it on an angle but still had the same results. Like I said I had the power head rebuilt by a very reputable shop and they also changed out the shift rod and a new water pump carbs were rebuilt. The old power head had lower even compression so I just wanted to freshen up the motor. I am still adding some two stroke oil to the fuel tank in addition to the injection system The mechanic wanted me to run it at 100 to 1 in the tank for break in .. Is it possible something is going on with the oil or is it just oil not burnt from the engine and the water pump is going prematurely. Sorry for the long post thanks for your input.

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That doesn't sound right to me.

50:1 is generally the normal gas to oil ratio.

100:1, 100 gallons of gas to 1 gallon of oil, the engine is not getting enough oil, especially at break-in.

Usually a break-in calls for more oil to gas, like 25:1
Twice the amount of oil to protect the rings, pistons, etc.

Not sure what this would have to do with the water pump pressure however.
Have you run this in the water yet?
Not on the muffs.

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Joe I thought it was 100 to one but I have to check to make sure. But it ran great all summer long I did not think the two issues could be related but could that oil be fogging fluid . I did not launch it yet this year. I am debating weather or not to change out the pump? Thanks for your help..

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A lot of the fogging oil will blow out through the exhaust and collect in the bucket the first time you run it so hopefully that's all it is.

Adding 100 to 1 directly to the fuel tank plus the 50 to 1 from the VRO sounds about right to me. The extra oil will just make the engine run a little smoky, nothing should be leaking. If the oil is coming from the lower part of the engine it could be the upper gear casing seal (just below the water pump) but not likely you'd see enough to notice it. If it's coming from the bottom of the engine itself you may have just over filed the VRO tank (assuming it's under the cowling) or maybe a hose is loose.

Call the mechanic or bring it back if you're not sure.

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Bob,

Good catch.
I missed the part where he said he still had the injection system hooked up.

Still, many recommend double oil then.
50:1 from the VRO and 50:1 mix in tank during break-in.
(EDIT: that would make it a total of 25:1 ration giving it double the amount of oil ratio to the gas.)

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Hello Jodee95 and please detail for me, does your Yamaha 90 have the 2-stroke (plastic) oil tank mounted next to the carburators?

If so, double check the small rubber hose connections between the oil tank and oil pump. Check and verify that the oil (plastic) tank and/or hoses haven't developed a crack/leak.

With a good light source you should be able to inspect the lower perimeter of the power head (where it attaches to the mid-section) just to rule out a block gasket leak or oil pump assembly leak.

As mentioned previously, with the oil enriched mix you are/have been using the outboard will blow the excess through the exhaust tuner within the mid section. Where exactly are you seeing the 2-stroke oil residue on the outboard? If possible, access the lower carb fuel bowl drain screw and capture the draining gas onto a clean white cloth/paper towel just to view the amount of oil present in the fuel.

The spark plugs have not been oil fouled? Pull the plugs and inspect their condition. Typically after a rebuild/break-in run period the spark plugs will be replaced with a fresh set because of the oil enrichment most mechanics prefer.

Happy boating...
Angel M.