Is this motor toast

[NickCawks]

The title might be a little misleading. Obviously this motor is toast at the moment. The real question is can I rebuild it?

I have attached some pictures of the damage that was caused in the block as well as a couple of pictures for the cylinders and pistons.

My main question is if I put a new crank in will the rest of the motor be fine.

*Keep in mind that the only thing I actually cleaned before taking these pictures is the bottom half of the block. The top half of the block, cylinder, and piston were not cleaned up so you may see some flecks of metal in some of them still (especially the upper half of the block).*

Block - Has the pitting gotten to a point where I need a new block? It does not seem to be all that bad to me, but I wanted some opinions from those of you much more experienced guys out there. Another question with the block is; are these things able to be machined/honed?

Cylinder - I am seeing little to no damage, in fact, I can still see the cross-hatching on most of the cylinder. What do you guys think?

Piston - Though I can visibly see these verticle lines on the side of the piston when I feel them it feels perfectly smooth.

Just trying to weigh my options here. Should I just go ahead and buy a whole new motor from SBT, or can I get away with just buying a crank and slapping it in this thing?

I can always take some more pictures, just snapped these off real quick before I had to walk away in disappointment (lol).

I appreciate any input you guys have for me and know that I am in a bad situation already so no sugar coating necessary.

 

[mikidymac]

Cases look fine.
Pistons and worn out and so will the cylinders. You will need to have them bored oversized and larger pistons fitted.

 

[NickCawks]

If that's the case I'm just gonna buy a new motor. These have already been over bored 3 mm. With the combined cost of crank and bore, hone, new pistons I'm already almost up to the cost of just buying one from sbt with a warranty.

Thanks for the response miki

 

[NickCawks]

I have been weighing my options. Just spoke to Tom over at Seadoo Engine Shop. He says it sounds like it was a combination of having the original crank and the +3 overbore contributed, by creating too much rotating-mass on the crank bearings.

Any of you guys have experience with his motors? He explained the main difference with his motors are they mill out the oil passages going to the outer crank bearings as this tends to be a big failure spot. It also comes with a two-year no-fault warranty so im not super concerned.

 

[AKnarrowback]

Not sure saying drilling out is good advice.

The polaris xlt triple motors were famous for loosing the pto bearings. When I rebuilt mine I drilled out the oil feed hole and milled a groove into the case to provide a feed to both bearings, so a little extra oil won't hurt.

It's your call.

 

[mikidymac]

Do your research very carefully here about SES. That's all I am going to say.

Also thousands of seadoo engines are running stock oiling without any issues. All the bearing failures I have seen are from water ingestion or just old age, not oil starvation.

 

[AKnarrowback]

Sort of what I was thinking.

Rotax twin cranks are pretty bulletproof. My fix on the xlt was an experiment.

As for the larger pistons causing more crank stress???? Again, this should not be a problem.

 

[mikidymac]

I agree with AKnarrowback, oversized pistons would have nothing to do with the crank failure.