15hp 2-stroke Rebuild

[morganstx@gmail.com]

Just bought ($700) and started to disassemble a 2003 Yamy 15hp stroke - its a project for my sons 13' whaler. I got a eBay shop manual, but am looking for some experienced feedback.

The engine started easily, idled smoothly, mid-range power seemed normal, top-end was rough and surging and not producing full power.

Pulling it down: The carb was clean and main jet looked fine. Removed head (sheared only one head bolt), noted some light cylinder scoring.

Haven't pulled the lower unit apart yet, but it was mostly out of oil, but no indication of water in oil.

Plan is to order all the parts it needs, so far I'm thinking:

Carb kit
Water pump kit
piston riing set

Main & con rod bearings?

[boats.net]

If cylinder is scored may need to rebore cylinder and order oversize piston and rings.

[morganstx@gmail.com]

Yep-the bottom cylinder was moderately scored,(its always seems to be the bottom cylinder) as was skirt of that piston, probably more than just honing it, but the machinist will let me know.

[morganstx@gmail.com]

Parts List

Got the cylinders mic'd and inspected, the light scoring is below the ports and looks ok to hone and reuse, bearing play is within spec. So appears replacing pistons and rings is appropriate. Made up a parts list of pistons, rings and several kits, plus some misc items.

Attached a PDF parts list, would one of you guys mind reviewing it?

I assume this is a good source for these parts, OEM, price, etc...

Shipping to the Virgin Islands, have a Miami freight forwarder if needed.

Thanks!