90 sn superjet- cracked/ blew hole in motor

[myblackz28]

i have a 90 superjet and it was not running right, seemed like it was sucking air from somewhere so i went through the fuel lines, the carburator and carb gaskets and the hole bit. well the last time i tried to start it it fired right up ran rough and i heard a pop, ting and it wouldnt do anything from there. sounded like the battery was drained cus all it would do was make a click noise. it had a brand new battery and i went to change the starter because it was cranking slow. well went and started unbolting the starter and there was a hole about quarter size in the bottom of the block and a crack right next to the starter and a crack just above the driveshaft of whatever it would be called. any input on wat would cause this? also it was a j650 b motor, and i have another bottom end from a 701, so what wouldi need to do to convert to a 700? i know i need pistons, and bore the walls, what else would be needed? thanks

 

[Matt_E]

I would be guessing that something lose got knocked around in the bottom end, causing the crack.

Just get a 701 motor complete and bolt it in.

 

[myblackz28]

thats a lil more than i want to spend as tempting as it is.

 

[Matt_E]

What is your budget?

Anyways, take your motor apart and see what the damage is.
It's possible your crank is still good.
You can use that, your carb, all your electronics to build a 701.
All you'd need are cases, cylinder, and head.
You can even forego the cases and modify your existing cases (eh, never mind - you said they're cracked).

 

[DBLOCK]

Since you have another bottom end from a 701, you'll need a 61X cylinder...

What is the part number on the upper case half? This will determine carb setup(s) available to you.

If you can salvage the flywheel and stator assembly, I'm guessing you shouldn't need new electronics.