CMB45RS EVO gold Head Crank removal

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Joined
Feb 19, 2014
Messages
31
I scored this engine second hand and would like to replace the crankshaft bearings before I run it but cant figure out how the crank comes out.
I've removed circlip, wristpin, piston and liner and logic told me if I take the big end to BDC and pulled it out and rotated thread end up toward the top of the engine the crank would rotate out of the case but it won't come .

Is there something I am missing here. I don't want to force anything in case I damage the crank or case.

Hopefully some of you CMB engine wizards can explain where I am going wrong.

Grahame from New Zealand.
 
Turn the crankcase upside down and turn the crankshaft until the rod is as far up as it will go. Now bring the crankshaft out towards you keeping the rod clear to the top of the bore and wiggle it around a little and it will come out. It has to go back in the same way it came out.
 
2, 3 inch lengths of brass tubing, smaller 1 longer. put clip in larger slide in smaller tube, line up an smack with small hammer. Bazinga!
Yes, that's how we've always done it, with exception of chamfering outside of larger dia tube where it interfaces with pin pocket in piston- just stabilizes a bit.
 
See also this link from Modelgasboats for a zenoah but principle is the same
https://www.modelgasboats.com/magazine/how-to-articles-mainmenu-606/497-piston-c-clip-tool
This is why I contribute, and enjoy being part of International waters. I start off with one problem then it leads onto other tips to make life easy. Having read the Modelgasboats article I have a lot of "Jesus clips" floating around my workshop! lol. Also thanks to the guys above for their contributions. Its Saturday morning here in New Zealand so now off to the cave to make some tools for me Zenoah's and the CMB.
 
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