Yamaha oiling problem
 

I finally got the boat in the water yesterday and it ran great. 96 Yamaha 250. When I got back to the marina I noticed an oil slick behind the boat. I pulled the coweling off and found that the engine's main oil tank was overflowing. I did a little web research last night and it seemed that replacing the float sensor in the tank would solve the problem. Unfortunately its still overflowing out of the tank and also into the air box. It looks like the oil control unit is built into the computer on my engine $$$$ so am I totally screwed here or is ther something I may be missing?

That happened to both my 1986 150's. I ended up taking the drive gear out of the pump, pinned the float to "full" to prevent alarms, and ripped the remote tanks and wiring hoses and pumps out and pitched them over the side into the yard. If you are electrically inclined i wouldn't doubt it one bit that you can build your own oil computer. Its just a bunch of switches that turn a pump on when oil gets down too low and turns off when it gets back up.

If I recall MJ had that same problem on his motor....forgot what he said or cost to fix it....

The float switch is the primary cause of this problem, but are you sure the manual switch isn't on? There is a toggle switch on the engine port side I believe to manually fill the engine mounted oil tank. If left on it will continue to pump oil up to the tank I believe.

i had the same problem with my 150 merc, and it was that the cap was broke and was not tightening it sepperated from the oil tank, if the cap is on tight i dont see how it could be overflowing?

The YAMAHA system is nothing like the MERC system. It uses a remote main tank, then a small engine mounted tank. The remote tank uses a small electric pump to transfer oil up to the engine mounted tank and is triggerred via a float switch in the engine mounted tank. If the pump stays running it will run over and pour oil out.

yep i had the same thing it was the float switch in the remote tank, $125 to replace at my dealer!!!! but worked like a charm!!

Checked the switch today. It always springs back to off position so i don't think thats the issue.

Maco Did you replace the float sensor in the main tank (engine) or remote tank on the boat?

the oil tank on motor was leaking so that is the float i replaced