New Briggs & Stratton Fuel Pump Leaking Fuel

Small_Engine_Newbie said:

I have a transplanted (by the previous owner) Briggs & Stratton 17.5 HP engine in a Craftsman LT1000 riding lawn tractor. When I got the machine I put a battery in it to see where I was at as far as the engine starting/running. It fired right up but ran rough and after shut down the carb overflowed with fuel. Suspecting a stuck float I removed the carb and then the fuel bowl. It was indeed filthy inside. I decided to replace the carb with a new one instead of rebuilding as it was in such rough shape internally. I changed the oil (looked old...not thinned by fuel or any other visible worrisome contaminants), replaced the spark plug, fuel filter and air filter. After I completed my repairs I tried to fire it up. As I watched the fuel filter I noticed it did not fill with fuel as I was cranking. This engine has the 3 line plastic fuel pump on it. I assumed the pump was likely bad so I replaced it with a new, genuine Briggs pump. I again attempted to start it and again no fuel was visible in the filter. I did verify that the solenoid on the fuel bowl was functioning. I then disconnected the fuel line from the filter and poured fuel directly in the line thus filling the fuel bowl in the carb. I also disconnected the other end of the fuel filter and poured fuel directly into the filter. I reconnected all the lines and started the machine again. It fired right up and ran smooth. It ran until the fuel in the carb was exhausted and then died. The fuel filter also emptied. When I attempted to restart it fuel came out of the brass breather on the front of the fuel pump at a fairly significant rate and the machine never fired. I drained the fuel from the tank and here I am looking for advice. I searched online and found a multitude of bad pump scenarios leaking oil but I couldn't find much in the way of leaking fuel. I found one, single post that mentioned fuel running out of the brass breather was likely a bad head gasket but if that was the case would the engine have run so well while there was still fuel in the fuel bowl and line?

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Small_Engine_Newbie said:

This one has a fuel pump. And I just solved the problem. I was in a hurry to try and get it running the first time. I just matched the connections from the old pump to the new. I just went out and studied it and realized the previous owner had the hoses connected incorrectly. So obviously me copying the old pump now had the hoses incorrect on the new pump. It's funny.....when the vacuum hose and fuel inlet hose are in the correct places the pump pumps fuel, doesn't leak and the tractor runs! Good example of take your time and never assume.

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