yamaha 55 outboard, oil coming from exhaust

darragho connor

hi
i have a yamaha 55 2 stroke on my lencraft, the outboard is from around 1992 the model number is 663 , 55 bed L. when i start her up and run her in the yard she runs like a dream no issues, cooling perfectly and reving up no problem . But when i bring her down to the sea again she starts no issue but when i put her in gear she wont run any faster than idle and a gloopy oil slowly seeps from the exhaust, she is also seems to remain in gear.
can any one help ? i have had her with my mechanic who is at aloss asto what could be the problem

davlacey

sounds like a gearbox problem when its under load try it in a barrell just to see if the same thing happens.

fergal.b

Start off with the cheep a cheerful stuff first

Check vent screw on tank.

Check primer bulb and valves.

" fuel lines for air getting sucked in.

" check fuel filter, use new fuel with the right oil mix.

Do a compression test and check your spark plugs and leads.

Clean the carb.

After that you can start by looking at the starter or the CDI, it's quite common to have a bit of oil coming out the exhaust with two strokes and if it's not firing right you can get a bit more also when you have the engine in the up position while transporting you can get extra oil coming out when the leg is put back down. when you say she seems to remains in gear is that when she is out of the water as well ?

P.s. don't rev the engine up to high on the dry as it can over rev without any load on the prop.






.

breghall

sounds like a cylinder or two ain't firing and the unburnt fuel is coming out the exhaust. It would explain the lack of power too.
Do everything Fergal has said and if still none the wiser whip of the head and see if anything noticeable catches your eye.