i just clean out the fuel tank[had somekind of orange stuff in it] changed fuel filter ,drained the float with the drain hose,filled up with fresh gas and added some heet to the gas.ran great for about a mile than started losing power,backfiring,with the throttle wide open, surges ,but if i put the choke on full, power about 70% or so came back still sputtered abit ,DO i need to also clean the fuel pump and float bowl TOO TRAIL BOSS 325

 

Try a new fuel filter.

 

maybe you should check your etc switch on the throttle cable. The cable is not supposed to have any slack in it this will make it backfire, backfires are usually caused by ignition not a fuel problem.Just a thought

 

Sounds like fuel filter or water in the gas. If there is a lot of water in the gas, that could cause the symptoms you describe. Heet draws water through the system. If there is enough water, it will 'weaken' the heet, making it run way too lean. Choking will help offset this.
I would suggest fuel filter change. When you have it off, and the line not hooked to anything, put the fuel selector to reserve, and run about a cup out. This will hopefully flush out any gunk in the tank. Re-connect the fuel line with the new filter & try fresh fuel. If there was water in the system, it will still run sluggish until you get the stuff in the carb run through. Either that or drain the carb.