OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines B&S compression release

I have a B&S 17.5 hp twin cylinder riding lawn mower that I cannot start because the starter cannot overcome the engine's compression stroke. I suspect the compression release valve and loose valve clearances but I cannot find where to adjust. I have removed a small plate to expose valve stems but no adjustment. Help?

Unfortunately if the release has gone (and its one of their common downfalls) its on the cam gear - ie you have to tear the motor down to put in a new camshaft/gear assembly.

Hopefully its just the valve clearances too loose.

for starters, could you please post a couple photos of the motor and the model type code number. it could be on top of one of the valve cover (if its OHV which I hope it is) or somewhere on the metal cowl (if its one of the old opposed boxer motors)

If I was stuck with this situation I would be seeing if I could fit a PT decomp valve to each cylinder Bitch of a job but better than stripping the motor down. Are you sure the battery and starter motor are in good condition?