No compression

[Docmonroe]

I was given a Briggs and stratton 21 hp engine model no 33m777 0111 b1 . was told it was rebuilt 3 years ago but never used. Put on my tractor will not start . after checking found out has no compression. anybody have any ideas before I start pulling it apart.

 

[Scrubcadet10]

I would remove the valve cover first, and be sure a valve isn't stuck open.

 

[Tinkerer200]

Yeah, check as above first but I suspect thrown rod.
Walt Conner

 

[Docmonroe]

Pulled valve cover both valve opening and seated pulled plug piston moving . I`am going to pull head and take a look at head and cylinder and check for cracks. I wonder if a ring got broken when it was rebuilt.