Briggs exhuast valve rocker loose after adjustment. Tight set screw.

[Obie 2 relaxing]

Rebuilt 18hp briggs. Adjusted the valves 1/4" past TDC n tried each while compression down stroke at .004. The exhauast valve rocker extremely loose at rest while the intake holds its clearance n stays in place.
Why does the exhaust valve become so loose- near spin it!
Had a new lifter cam replaced a year ago.

 

[bertsmobile1]

Because you are setting them on the exhaust stroke, not compression stroke.
You use the TDC that happens just after the inlet closes