B&S Opposed Twin Fuel Problem

Pillchuck

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Ok I need help. I have a Briggs and Stratton 19.5hp opposed twin engine with fuel issues. I am able to start and keep the engine running as long as I poor gas down the carb. Therefore, it must be a fuel pump problem, however I have replaced the rebuilt the pump, and when that didn’t work I bought a brand new carb with pump on it. So that didn’t work and blamed it on maybe getting a bad carb/pump and returned it and got another one. Well same dang problem. I have tested the fuel line and fuel runs freely, I have opened up the carb and poured fuel into the bowl and it will until that gas runs out. I have tested the vacuum line and air is moving to the pump. What am I missing????
 

ILENGINE

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Air leak in the fuel line between the pump and the tank, or maybe the pump is dry and not sealing well enough to create a vacuum to start the pumping process. Maybe try a fuel tank about the carb and see what happens and if it starts and runs that way then lower the tank to below the carb and see if it will keep pumping
 

Pillchuck

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Thanks!!! I will try these suggestions. I do have a shut off valve and a filter on the line so maybe one of these is leaking air. I will also try elevating the tank.
 

oologahan

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Have you replaced the filter and its in line the right direction?
 

Hammermechanicman

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Do you have the fuel and vacum pulse lines hooked up correctly? The pulse line goes on the bottom of the fuel pump and the fuel line goes on the side of the pump. Is it a 3 screw or 4 screw cover on the fuel pump.
 

Pillchuck

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Have you replaced the filter and its in line the right direction?
Yes I double checked. I’ve made that mistake before. The fuel flows in the line with no obstruction when not on the pump.
 

Pillchuck

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Do you have the fuel and vacum pulse lines hooked up correctly? The pulse line goes on the bottom of the fuel pump and the fuel line goes on the side of the pump. Is it a 3 screw or 4 screw cover on the fuel pump.
I have the four screw pump.
 

bertsmobile1

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The pump has a check valve in it , otherwise it could not work .
Thus fuel will only flow through it one way.
The inlet & the impulse are together, inlet in the side & impulse on the top.
The outlet is on the opposite side.
If the pump is Ok you should e able to suck fuel through it .
If you can not then the check valve is stuck.
They rarely ever cause any problems
 

biggertv

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Ok I need help. I have a Briggs and Stratton 19.5hp opposed twin engine with fuel issues. I am able to start and keep the engine running as long as I poor gas down the carb. Therefore, it must be a fuel pump problem, however I have replaced the rebuilt the pump, and when that didn’t work I bought a brand new carb with pump on it. So that didn’t work and blamed it on maybe getting a bad carb/pump and returned it and got another one. Well same dang problem. I have tested the fuel line and fuel runs freely, I have opened up the carb and poured fuel into the bowl and it will until that gas runs out. I have tested the vacuum line and air is moving to the pump. What am I missing????
Those pumps are trouble and always will be. Ethanol. Rebuild every season or else. Get an electric pump off amazone or fleabay (9.00) problem solved. leave other hoses hooked up, no problems, starts first time every time 18.5 brigs runs better than ever. Sorry, forgot how I hooked up electric, pump runs with key ON.
 

rancher_mac

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Those pumps are trouble and always will be. Ethanol. Rebuild every season or else. Get an electric pump off amazone or fleabay (9.00) problem solved. leave other hoses hooked up, no problems, starts first time every time 18.5 brigs runs better than ever. Sorry, forgot how I hooked up electric, pump runs with key ON.
Just came across this. I started a topic on the Briggs engine forum about installing an electric fuel pump. Did you go out the outlet from the electric pump through the inlet to the carb pump and just cap the pulse input?
 
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