The Hercules Engine News

By Staff
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20601 Old State Road Haubstadt, Indiana 47639

It will soon be time to start dragging those engines out of
storage to get them ready for another show season. That means that
a lot of us will be tuning up Hercules, Economy, ARCO and Jaeger
engines. After sitting around all winter, the fuel system may need
some attention. Starting out at the fuel tank on the normal hit and
miss engine, let’s check it all out.

Does the fuel tank have any leaks? Does the fuel tank have loose
dirt or rust in it? A dirty fuel tank should be cleaned out if
possible, and then some tank sealer should be poured in, sloshed
around and then the surplus poured back out. Not only will that
prevent small leaks, it will also ‘glue’ any loose material
down, so it won’t move into the rest of the fuel system. Set
the tank aside and let it dry a couple of days. The included
illustration is a schematic of a typical Hercules system.

If the tank has a vent on the top, check to see that it is open.
If there is no vent, drill a ‘ hole in the top front and solder
in a short piece of ‘copper tubing. The vent is necessary to
make the filling of the fuel tank go easily. The fuel pipe coming
from the tank should have a brass screen soldered into the end of
it to prevent particles from entering the rest of the fuel system.
Check the fuel pipe to see that the inside is clean. There should
be a ‘ pipe T on the outer end of the pipe with a removable
pipe plug, so the tank can be easily drained after you are through
with the engine for the season.

The check in the check valve cage should move freely and not be
sticky from old gasoline. Put a few drops of liquid in the top of
the check valve to see that it is sealing. The fitting that screws
into the top of the check valve must have notches filed or sawed
into the bottom rim of it, so that when the check rises, it does
not shut off the fuel going into the line to the mixer.

If the engine still has its original fuel line and fittings, it
has likely been screwed on and off many times. To as-sure tight
joints, it might be well to use new fittings and make a new fuel
line with new ferules. It is also a good idea to use thread sealing
compound or tape on all pipe thread connections. The fuel
adjustment valve should have a nice tapered point without rust
pits. A new one can easily be made from
5/16‘ NC threaded rod.

Have your ever noticed that the fuel inlet hole in the mixer is
not in the center but, rather, at the top of the threaded hole
where the fitting goes in? That is so that the fuel will stay in
the line during idle strokes and not run out. In fact, no part of
the fuel line to the mixer should rise above the mixer fitting.

Now, if all things are done right and with fuel in the tank and
with the choke on, a couple times through the intake stroke should
bring fuel to the mixer. Assuming everything else is in proper
working order, the engine ought to fire right up. If the engine
won’t start with fuel in the mixer, it is time to stop cranking
and to start looking for ignition problems. But that is a problem
for another time.

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