200s no compression?

[Mudder F er]

I just bought a 200s motor on ebay. It just arrived it was supposed to be running but its not. It has no compression. What can be the cause? I've pulled on it a bunch got it to turn on for about 20 seconds. It barely made any noise. I emailed the guy I bought it from, but in the meanwhile waht can this be. I have never had this problem. Thanks

[Lots_Of_Nothing]

Do you have a sparkplug in the engine? Is it tight? Check your valves.

[Mudder F er]

The plug is on tight, there is a small crack in the case it leaks a bit of oil ca that be a cause? Or does the piston hane anything to do with it? thanks

[MTS]

take the valve caps off the top of the motor and turn it over and look at the valves to see if they are moving....if not then pop off the cdi cover and see if your timing chain is busted or fell off

[Mudder F er]

its all moving, and timing chian is on tight. could the crack on the right side engine case be the cause. I put some liquid gasket on it, but I dont think its thge cause.

[70binder]

do you have a feeler gauge? if so, then pop your head, and see how thick of a shim you can get between the cyl (anything thicker than .004 if i remember reading right and you're losing all your compression to there). if you can get your piston out, check the ring gap (put the ring in the cyl like it would sit on the piston) and check the gap (.050 is what it is on International i think, but you want as little gap as possible) also, your piston could be out of round, when you check it with the feeler gauge make sure you check it in more than each side. dont know if this'll help, you may also have a bad head gasket. if you don't have any on hand, grab a cereal box, trace your gasket on it, x-acto it out, and you'll probably need one or two depending on how thick your gasket is. note: the makeshift gaskets are NOT for running around, they'll deteoriate with time fairly soon.

hope you got all that, you other guys wanna check what i said over and make sure it's ok? i dont want this guy ruining his 200 motor :)

[grundlegrabber]

Check the easy things first. Get a good manual and check the valve clearances. Remove the valve caps on the head. Turn the motor to top dead center on the compression stroke and see how much clearance is between the valve stem and rocker arm. A tight valve will cause major compression loss. If the valve clearance is ok and the plug is in tight, you're gonna be doing a top end rebuild. Hole in the case will not cause compression loss, compression takes place in the cylinder above the piston rings.

[Mudder F er]

Thanks for the info I will try it all later today.

[Mudder F er]

I checked the valves they were both very tight no movement. I was able to adjust one of them but the other will not move. Just to verify they have to be checked when the piston is up, right? Im gonna take the cover off today and see what I can do. I tested the pull by covering the plug hole with my finger and it seemed to have more compression.