1995 Jon Deere sabre

[Damato]

I have a 13 hp Briggs on a 1995 John Deere Sabre that will only run with the choke closed. I overhauled the carb and changed the intake valve with a new Briggs valve. It still pops through the carb and will not run with out choke closed. Please help.

[fixer]

popping or spitting back through carb. is usually an indication of intake valve not fully closing during exaust stroke or a partually sheared woodrift key on flywheel.

[Damato]

I have put in a new key and lapped and set the proper clearence on a new exhaust valve. Seems like the motor has a lot of blowby with compression at 60 PSI.