Flywheel problem please help
 

im trying to get the flywheel off my engine but when i hold the flywheel and turn the nut, the piston is moving too. what could be the problem. Any answers would be appreciated

It's not tight enough on the collett. you need to lock the piston with a tool, or a soft material, like a pencil eraser, or a soft plastic

what could i use that wont damage the piston

Use a popsicle stick/pencil (NOTHING METAL/HARD) and insert it through the exhaust port.

the best thing is to buy this:

http://www.amainhobbies.com/product_...and-21-Engines

Wow i didnt think of that i will try it thanks for the answers

Or for something cheaper and better quality, http://www.amainhobbies.com/product_...ing-Tool-12-21.

Do it harder.

Fold a large zip tie in half and insert it into the exhaust. Works perfectly and is cheaper than both of the other options.:D

I like the looks of those tools, but then you have to take the backplate off, which can be a pain if you are in a hurry to get a flywheel off or on.:nod:

ok i got the flywheel off but when i put it back on and pull the pull start it doesnt spin but the shaft that the flywheel and clutches are on does, whats the problem

Your flywheel is not tight on your collette, or your collette is not tight on the shaft. You need to lock that Clutch nut down really tight, with some threadlock. It should snug up both the flywheel, and the collette. If it was all working good before, you just didn't tighten it enough

are you saying that your stoping the piston from sliding to the top with the zip tie this way in order to not have the crank shaft not move?

it wasnt ever working right before. See what happened is i took the stuff (flywheel, clutches,clutch bell,etc) off my old engine which was a O.S. .15CV -X and put it on my new one which is a O.S. .18. And if i i ty to tighten anymore the pullstart will break because when i turn the nut to tighten it the pull start cord is being pulled down. Agh this is a mess, i think im going to have to take it to my LHS and see if they can help me

Thats what he's saying. I refuse to put anything into any of my engine ports. I tried it once and that metal is so sharp, it just cuts pieces off anything you shove in there, and there's a really good chance that one of those pieces will fall into your crankshaft. It also puts unwanted stress on your con rod..sorry Jammin, gonna have to disagree with you on this one:( your way is faster and easier, but not worth the risk IMO)

If you just have to use something to stop the piston then at least do it so that you pose the least risk to the engine. Turn the engine over (head down) and turn the crank so the exhaust port is open. Pour in about a teaspoon of fuel or oil. You can't compress a liquid.

Yes, if you have to torque to the nut to extremes you might bend a rod. But if you have to crank on it that hard the piston would already be damaged from ANY other type piston stop.

When installing a flywheel first always make sure the mating parts are grease free.
Ed M.