Scout 800 Fuel Problem

[duffelpud]

This weekend I installed my refurbished left side gas tank, fuel lines, fuel switch and rebuilt carb. I then attempted to start my Scout. Here are the results. I welcome suggestions. Note that the fuel pump was removed and cosmetically cleaned and the unit tested by hand - it seemed to be pumping both air and fuel adequately. At any rate, I cranked and cranked (after putting about three gallons of fuel in the tank) to no avail. I tried pouring a little gas in the carb and only got an occasional sputter. I then disconnected the fuel feed from the pump and rigged a gravity feed directly from a jug sitting on the radiator. After a a little bit the old engine fired up and ran like a champ, although it idled high. Everything looked and sounded good with only a little clicking coming from the valves. I located a giant sucking sound coming from a rat-chewed hose that bent down from a fitting on the side of the manifold to the vacuum pump on the top of the fuel pump. When I plugged this hole the idle dropped to what seemed like normal. I then reconnected the carb to the pump and tank, started the Scout back up and set myself to correcting and connecting the vacuum hoses from the wiper and the manifold, hoping that having fuel in the carb and line would magically fix the fuel flow problem. After about a minute or two it died and wouldn't start again. Here are a few other troubleshooting tidbits:

- When I disconnect the fitting at the carb and crank, no gas comes out of the fuel line from the pump.

- All of the lines were tested and cleaned prior to assembly.

- The fuel tank switch was rebuilt and is in working condition.

- The vacuum pump on top of the fuel pump is blowing and sucking air vigorously.


I plan to test the fuel pump next by rigging hoses directly to it and a coffee can of gas to check flow. I also plan to check the fuel lines again by blowing air backwards through the system and listening for air in the fuel tank. Any other suggestions?