unknown engine, what to check? help please (comp test)

[aaroffee]

hey folks, starting a new build and i've got two engine's in my possession one is seized that i've been working on freeing it up all this week with no luck as of yet (been sitting for approx 8 years with no carbs/exhausts or anything covering the holes ) at this stage ill probably just pull the head off and tap the pistons if it doesn't free up but i purely bought it for a parts engine so i'm not to fussed but any tips????

Anyway my "good" engine spins freely, valves are opening and shutting fine (have not check clearances) but i cant get any reading on my comp tester, it pressurisers it (1/2psi my guess) but nothing on either side, im wondering if it could be due to having the clutch side cover off and also the oil breather unit is missing too, also have the kicker shaft out or have i got some fired rings in there? any help would be appreciated by me and my wallet before i tear it down and rebuild.

thanks Aaron

 

[TwoManyXS1Bs]

A lot of good tips in here:

http://www.xs650.com/threads/first-xs650-build-what-to-look-for.43453/

Also do a forum search on "piston pusher".

No compression on the other engine may be bent or not-seating valves. Put a cylinder at TDC and shine a bright light into a port. See if any light appears while viewing into spark plug hole...

 

[gggGary]

Bring it up on TDC compression stroke, secure crank from turning, blow air in the plug hole easy to hear where the air is going.