# B&S fuel problem



## Matacan (Sep 2, 2005)

B&S 42E707 19.5 hp Sears Chassis
2631-E1
98050458

Well folks, this one has me stumped....

Problem: No fuel to carb. Can prime directly down carb barrel and it runs until fuel consumed. (used to run until shutoff with this procedure)

Steps taken so far:

rebuilt carb including pump diaphram.
replaced float
cleared fuel line and filter from tank to carb pump intake ok
checked hose from block to pump ok
checked venting on gas cap ok

What am I missing here? Direct prime= runs great for a minute or two.
Any suggestions would be greatly appreciated. Feel free to email me directly
[email protected] HELP


----------



## bugman (Aug 12, 2004)

make sure the carb isn't sticking, does it have adjusting needles? also check the tank for any clogging near the pickup? also it uses a fuel pump?


----------



## Matacan (Sep 2, 2005)

It uses an impulse diaphram type of pump on the carb and I replaced/rebuilt that. All lines are clear and free running.


----------



## bbnissan (Nov 7, 2004)

This is a problem I have seen a few times, especially on larger engines where the fuel lines are routed close to the exhaust or head.... Take a look at the fuel line and make sure there are no pin holes or small cracks, especially on the top side of the fuel line. Also, make sure that there are no cracks or rips in the vacuum line from the crankcase. Either of these will cause the fuel pump to be very weak.


----------



## Matacan (Sep 2, 2005)

bbnissan said:


> This is a problem I have seen a few times, especially on larger engines where the fuel lines are routed close to the exhaust or head.... Take a look at the fuel line and make sure there are no pin holes or small cracks, especially on the top side of the fuel line. Also, make sure that there are no cracks or rips in the vacuum line from the crankcase. Either of these will cause the fuel pump to be very weak.


 BINGO, Thank you! fuel line from filter around engine to carb, despite seeming clear, revealed a tiny leak under pressure. Replace that section and problem cured!


----------

