Looking for an engine for cheap it's a 1990 740 gl volvo 4cyl. 2.3 non turbo. Just need main engine got every thing else. My mechanic said no compression in cylinders 3&4 I thing rings are blown r broken. Any ideas out there besides engine change would be helpful. I had tapping noises then gunned engine to 50 mph and then it started shakin real badd and barley would get around. One spark plug burnt badd in back. PLEASE help

Peetz is right, head gasket, removed head, have shop clean up and make sure it's flat, put back on. Don't disassemble everything,that is, undo bolts to exhaust manifold, pull back from head, same with intake, you wont find an easier car to do a head gasket on. Good luck.

No compression in adjacent cylinders usually means a blown head gasket. Simple repair and a lot less messing around than changing an engine. If the engine was running well before this little problem and not burning oil, yank the head and fix it.
You might have to change your mechanic though.