Briggs knocking and low on power.

[hlw49]

I have never seen this but here was the problem. The throttle shaft was broken not moving the throttle plate. I would start and run but not fast enough to deactive the compression release. Causing it blow back through the carb. Replaced The throttle shaft put the throttle plate back in. It cranked and ran fine. Thanks for all that posted.

 

[ILENGINE]

Thanks for letting us know the fix. I have one customer with a rear engine snapper with a 8 hp briggs that has broken the throttle shaft 3 times.