Yong Heng Crankcase Swap

Greetings,
I am replacing a crankcase on my Yong Heng compressor that I damaged. The unit is disassembled to the crankcase and the motor. I have removed all four long bolts that holds these two components together. Do I have to remove any more from the crankshaft before the motor and crankcase come apart? I have a photo of where I am in the procedure as well as the rotating counterweight that attaches to said crank.

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If I have to remove more please suggest how to do so. I seem to be stuck. I am pulling apart the crankcase and the motor and it is not going anywhere.
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It is possible that this part unscrews before the crankcase and motor come apart. If so which way is it threaded and what should I use to restrain the crankshaft from the other side.
Regards,
Mr. Pepper
 
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I think it should just pull off. The bearing on the back side is probably holding on snug to shaft. I replaced the housing on my AV4500 and it's probably pretty similar. I had more issues sliding the new housing over the bearing when I was re-assembling. When you're asking about a part unscrewing are you asking about the shaft in the center. If so that's actually the armature shaft from the motor and it's a solid piece.
 
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I'd try supporting the housing with blocks of wood, and sharply tapping the shaft with a plastic or leather mallet (hammer and block of wood would suffice as well). Sharp raps are preferred, allowing the hammer to bounce off the shaft. (Disclosure: I have never worked on this compressor, but have had to drive many a shaft out of a snug bearing in my day)
 
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Ok,
F6Hawk had it right. I secured the crankcase and swung away with a hammer and a board.
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The crankshaft released. What was left was a bearing with some grit on it from seizing up. There was a compound of sorts that had melted off the copper coils too and was probably sticking to the crankcase as well. It was brittle and not the reason it was stuck.
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I used the four long bolts to reseat the bearings tightening them slowly in a star fashion. I'm waiting on a circlip pliers to replace the second stage piston then it should be ready to run. Thanks for everyone who helped.

Regards.