# B&S only runs on gas poured in carb



## poacher (Oct 8, 2004)

Hi,

I just picked up an older B&S model 81902 and can't get it to run properly. If I pour gas in the carb it will run nicely until the gas is used up and then stalls. If I choke it I can get it to run a couple seconds longer. Pouring a bit of gas in the carb once it is already running does not make it go any longer. I've removed the needle and cleaned the port and tried a different carburator, all with the same results. Its got a rusty old tank with a hole in the small compartment that the short fuel pipe goes into. I'm not sure how the fuel system works exactly but could this be the problem or is there anything else I should check? Thanks.

Poacher


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## bugman (Aug 12, 2004)

it might be the tank. now if it has a hole where a hole shouldn't be toss it. you need to either find a good used one or go to a small engine repair shop and either get a new or find a used one there. now if it looks fine but is rusted inside or under the carb seal if it looks repairable then fix it. carbs are alluminum and the tank is steel. just like they say opposite metals don't attract and they will corrode or rust the tank under the seal if it sat in the rain alot. now if the steel is pitted around or under the seal don't bother fixing with silicone or anything else it don't work it cause's more rust on the rust. now if the engine is lets say more than 5 years old go ahead and replace your diaprahm and carb gaskets. if the tank is repairable clean up the rust and paint it with paint made to withstand gas. now on an odd chance both the carbs need new diaprahms just check em first. if they look worn, torn or you can see tiny little dots of light shining through replace them first. they are cheap and most likely the problem. i had one that would do what you were saying and i replaced the diaprahm and problem solved.


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## doctorslotcar (Jul 25, 2004)

excellent diagnosis bugman--thumbs up


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## bugman (Aug 12, 2004)

thanks. i had a couple that one had the rope stuck along with everything. another where the brake snapped closed of course both were not taken care of set in the rain $20 pushers at a flea market. both ran great after some cleaning and minor repairs/paint jobs. got $150 for both afterwards. see small problems like that seem big and expensive when they are the opposite. like i allways say get in there and fix it and treat your engine with respect they will last you many years.


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