jakeboomer
Cadet
- Joined
- Nov 16, 2004
- Messages
- 19
Hello,<br /><br />I am having a problem with my '88 25 Horse Merc fuel pump. The carb is a Walbro WMC with integrated fuel pump. I have rebuilt the carb using a Mercury factory carb kit, and following the steps in my Seloc manual. I have rebuilt two other carbs, but on older OMC units.<br /><br />The problem is this. After the carb rebuild, it seems like no fuel is entering the bowl. When I manually pump the primer, it sounds like blowing air. I removed the carb and dropped the bowl. There was very little fuel in it. The fuel that was there could have been attributed to my squirting fuel into the carb during troubleshooting. With the bowl off, and the fuel pump still assembled, I attached the fuel line and pumped the bulb solid. No fuel drained from the valve inlet above the bowl. It appears the fuel isn't getting from the fuel pump into the carburetor. When I took the fuel pump apart, only the top half looked wet from fuel.<br /><br />In the diagram for my fuel pump, the diaphragm locations aren't shown. I assume the configuration of the pump should be - carb body >> gasket >> diaphragm >> fuel pump body >> exterior diaphragm >> gasket >> fuel pump cover.<br /><br />Does anybody know what the configuration should be? I changed the diaphragm and gasket order between the carb and fuel pump body back and forth. Either way, I cannot squeeze the fuel bulb and watch fuel drain from the valve inlet into the bowl area. <br /><br />The engine ran before this carb rebuild, but didn't idle very well. During troubleshooting the motor would fire if I sprayed fuel mixture directly into the carb. <br /><br />I know somebody on this great site can help me out. There is an excellent wealth of knowledge. Thanks in advance.<br /><br />To see the diagram I am referencing, you can goto<br />www.mercurypartsexpress.com - parts for mercury marine products - type my serial number OB246376 - and choose "carburator (25)". The diagram will show up on the right of the page.
