Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Could anyone suggest a fix? I have a small, horizontal shaft Briggs-Stratton engine that I'm trying to set up in a minibike for my son. The model number on the fan/starter cover suggests that it came from a vertical shaft engine at some point so I really do not know the model or power rating.

The carb sits on top of the gas tank and has 2 tubes that extend into the tank. The is one carb adjustment screw on the side of the carb. There is a device at the end of the carb that is manually pulled while cranking that appears to richen the mixture for starting. There is a cover on the carb that opens up to reveal a thin rubber diaphram with a spring underneath it. The pickup tubes that insert into the gas tank appear to be clean.

Here's the problem. The engine will start and it will idle. However, it will not rev up when the throttle is opened. Turning the adjustment screw does not remedy the problem.

Barring a solution, can anyone suggest a source for a relatively inexpensive 3.5 hp vertical shaft engine, 3/4" shaft with key? Jack's Small engines sells them new for $200.00. I'd like to get one for less$$.

Thanks in advance.