3.5 hp b/s carb under tank not starting...

[zanegrey]

hey guys..

I have a 3.5 (older ) b/s horizontal shaft engine.
it starts with ether but dies shortly after..

I replaced the side gasket and the gasket under and between the tank and carb to no avail..
can anyone give me some advice on getting this carb straightened out ...


thank you

 

[Lucky7]

Maybe give it a good clean? Just dissemble. Rinse with some carb cleaner. And clean all the jets.

 

[CarPlayLB]

the typical carb sits on the tank. The subject line says carb under tank, and you mention you replaced the gasket between the carb and tank. I'd like to see a pic of that. Most of the carbs that sit low are not attached to the tank. They are front mounted.

Replace the diaphragm if you have a tank mounted carb.

 

[jackeo21]

I usually wind out the mixture screw a bit, they start rough that way but you can quickly turn it in until it goes nice.

 

[buckeye]

I'm with Eric.
8 think he misrepresented the type of carb set up.
If it's a sit "on" the tank carb, did you change the diaphram?

 

[Havasu Dave]

If it's a sit "on" the tank carb, did you change the diaphram?

My thoughts too, although he said he changed the side gasket. The only thing on the side is the diaphragm.

it starts with ether but dies shortly after.

Fuel starved. If it's the Briggs Pulsa-Jet you describe, the diaphragm on the side sucks fuel from the tank via the long tube, pumps it through the pump orifices, then back down to the smaller "tank within the tank" where it is picked up for fuel feed via the smaller tube.

Here is an excellent description and cleaning segment, if we're talking the same carburetor. Disassembly, Cleaning and Repair of Briggs Tank-mounted Pulsa-jet Adjustable Carburetor