Rick wrote:
We have an 18 hp. twin fuel pump on the side of the carb . It was
working fine and then quit . It appeared that it was lack of gas as it
would start and run as long as you pored the gas in the carb . I
rebuilt the fuel pump and it still wasn't getting fuel . I took the
top off the carb and it was bone dry . I replaced the needle valve and
it still didn't get fuel . This time when the carb was apart I poured
some gas in the bowl and poured gas to the fuel pump line doing it
several times and turning it over to prime the pump . When I put the
carb back together it started right up and ran good . I took it out to
try mowing with it an again after about 10 minutes it acted like it
was starving for gas . Then it stalled again . Same problem . The fuel
pump seems to be powered by a vacum hose coming up from the
crankcase . Is there anything in the crankcase (filter)or something
that would plug up ? I can feel som air coming out of the hose when I
turn it over . I can suck fuel out of the gas line at the fuel pump
connection from the tank...Any ideas...Rick

Don't know them well (actually, at all ), but a couple of general
ideas -- sure there isn't a crack in the vacuum line leaking? Ends are
notorious for developing same -- if have a little extra line, I'd cut
off length that's on the fitting on each end and try just as an easy
thing to do...

What about a leaking gasket(s) on the intake side? Any chance of an air
leak there? The carb cleaner spray test while it's running is good for
finding leaks although may not help much on that side since it's all
fuel, supposedly. Although if it's in the vacuum path, could help...

Would need to know the engine and model number to try to find parts
diagrams to see how they're actually built to get farther or more
specific...

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