seized engine

[shooter114]

hey all i was riding my 99 yz125 the other day when it cut out and I slid to a stop.
I tried kicking it over but the kickstarter was stuck, i thought i seized the top end but when i removed the barrel i found the top end to be fine but the con rod only moves back and forth with no upwards or downwards action. Is it possible to free the con rod without disassembling the bottom end and what action should i take/what would be the most likely problem and how to fix it.

 

[2strokerfun]

Let me get this straight, you can rotate the connecting rod on the crankshaft journal, but the crankshaft won't rotate to make the rod go up and down?? If my interpretation is correct, first make sure it is in neutral (check the "Duh" items first). If it is , then you may have a frozen main bearing. The bottom line is that if it is either a main bearing or rod bearing, you'll have to split the cases.

 

[kawraper]

I had something similar happen on my 93 kx. Thought the piston seized in the jug. I pulled the top end off, piston was free, rod felt free but the crank wouldnt move. When I split the case I found the rod bering had blown up and a piece of it jammed btwn the crank and the case causing it to lock up.

 

[shooter114]

tried to get the swingarm bolt out but it won't budge, the bolt im talking about goes between the frame swingarm and engine its a hollow bolt with a flanged end one side and a nut the other, i put a stainless rod through it, a nut on one side and plate on the other, tightened it and then used a sliding hammer and i swear it hasn't moved a mm! any ideas or tricks to getting them out?