1996 SPI Used 587 Engine Swap (With Pics) - Options, Rebuild or Run?

[Seadoo Tuner]

My 96 SPI engine lost compression on one of the cylinders last summer (suspect crank bearings) so I picked up a used running 587 engine that has sat for a year or more so and am wondering on best options for it and am looking for advice and comments on each option :

1) Pressure test, sand/hone cylinder walls, change top end gaskets, and run it as is.
2) Top end rebuild
3) Split cases to put new outer crank gaskets in in addition to top end rebuild.

Would a light sanding of the cylinder walls suffice or does it need a hone? Hows the cylinder wash look?

Pics of the used 587 engine :

 

[AquaEye]

My 96 SPI engine lost compression on one of the cylinders last summer (suspect crank bearings) so I picked up a used running 587 engine that has sat for a year or more so and am wondering on best options for it and am looking for advice and comments on each option :

1) Pressure test, sand/hone cylinder walls, change top end gaskets, and run it as is.
2) Top end rebuild
3) Split cases to put new outer crank gaskets in in addition to top end rebuild.

Would a light sanding of the cylinder walls suffice or does it need a hone? Hows the cylinder wash look?

Pics of the used 587 engine :
View attachment 69020View attachment 69021View attachment 69022View attachment 69023View attachment 69024

#3.
If applicable...
Your correct on new gaskets/seals.
Use the same pistons with new needle bearings & new rings. With new rings, hone, need that cross hatch.
If I can make chicken salad out of chicken sh**, so can you.
Just don't step over a dollar to get to a dime.
You got this.
ps. Chicken salad does have a short expiration date.

 

[etemplet]

I would remove the cylinders and look inside the bottom end, check the crankshaft. The top end is in rough shape so keeping any pieces parts out of the bottom is the goal. If the carb was off the engine, the crank probably looks the same as the top end but good inspection would reveal the condition. I always flush the bottom end really good with diesel, let is sit, rotate the crank many times. Dump it out, blow it out and dry it especially the two little drain holes below the cylinders (I also drip oil into these holes and into the bearing cavity before final assembly) . Before flushing with oil.... I check for bad bearings, especially connecting rod bearings. Then if all is well, I flush with a good amount of two stroke oil and let it sit a few days. I don't replace crank seals unless I see a need to remove the cranks.

If you remove the crank, the process is less time consuming as you can visually inspect all the components and rotate each individual bearing to verify good condition. If you remove the crank, replace the seals. Good Luck !!