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Old 04-19-2009, 12:47 AM   #1
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Default Any experts on nitro engines?

I just purchased a team orion wasp CRF 21 and have installed the flywheel and clutch properly, but there is some slop in the engine itself. The crankshaft has 1/16 inch of play in it.

With my OS motor there is no play so I didn't want to start to break the motor in unless the slop is OK. Has anyone ever run into this?

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Old 04-19-2009, 03:22 AM   #2
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By play you mean in and out or up and down?
If it's in and out...make sure when you put the flywheel collet that you push it all the way down against the bearing by holding the engine from the cranckshaft.This way the crankshaft is pulled all the way forward and secured on the front bearing.
A bit of play is sometimes something you have to live with though.
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Old 04-19-2009, 06:17 AM   #3
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thanks it came with the shim attached, so I guess I will have to live with it. It's in and out play, and not enough that it would ever strip a gear of un mesh with the spur, but It's not going to make the piston go side wise up the head?



If any one else has any other advice I'm all ears!
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Old 04-19-2009, 07:23 AM   #4
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After you figure out how many shims you will need, push the collet all the way up against the shims/bearing (and pull a little on the crank nose at the same time) to make sure the crank is all the way forward.
When you tighten the nut, it will pull it tight. You shouldn't have any slop after that.
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Old 04-19-2009, 09:57 AM   #5
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Tiny bit of slop is normal,1/16 sounds like a bit more than normal.Do like itsshemp said above & pull forward on the crank while pushing back on the collet before you tighten the flywheel nut. Be somewhat gental you dont want to pull so tight that you put a side load on the bearing. .010-.015" is what I usually end up with for front to back play. Some bearings just have a little play front to back in them & thats ok.look at a spare wheel bearing & see how much play that has, it'll give you a rough idea what is acceptable for your crank. If your real worried take the back plate off & see how much the rod pin rubbed it after running.
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