Briggs Stratton only running on Choke

Hi

I have a Merry Tiller fitted with a Briggs & Stratton engine that is fitted with a Pulsa-Jet carb. It will only run when the manual choke is open. There is no diaphragm fitted to the carb as it is one of the early models. Any help in rectifying the above would be greatly appreciated. many thanks

Hello housman

All pulsa-jets have diaphragms, with the possible exception of the one fitted on the tiny fuel tank, more often seen on 2.5hp engines. As the engine runs on choke it can’t be too blocked. If you have fiddled with the mixture screw, turn in until it stops (don’t over-tighten), out 1.75 turns and the engine should run. Final adjustment is, when warm and revving hard,  screw the adjuster out until the revs fall, in until the revs fall, then back to halfway in between.

Almost all spares are available for the 3hp pulsa-jet engine. If briggs-bits won’t help either your description was too vague or they can’t be bothered. Your local B & S agent can get almost any spare you need, take the broken part and the model, type, code, details to ensure you get the right part.