52 Pontoon^ & Deck Boat March^2018 http://www.pdbmagazine.com
FgkhYjcgfgf][qdaf\]j2If you’re feeling adventurous,
swap the coil and plug wire from a cylinder that fires to one
that doesn’t. If the problem moves with the coil, replace the coil
that won’t fire. If it doesn’t, the ignition system is causing the
problem and needs to be diagnosed.>m]d;`][c2If you’ve checked spark on all cylinders and it’s
okay, you may have a fuel delivery problem. Many overlook that
the boat is out of fuel – check this first!Check to see that fuel is actually getting to the engine. Pump
the primer bulb (if equipped) and ensure it gets firm after a
handful of squeezes. If it doesn’t, check for leaks in the line, at
the tank or filter, and at the engine.If the engine has an electric primer, you can usually remove
one of the small fuel hoses from it that goes to the engine’s
intake or carburetor, and have a helper operate the primer
(usually pushing the key in) while you watch to see if fuel
squirts out.Newer EFI/DFI engines don’t typically have primers, so it’s
hard to check if the engine is getting enough fuel to start. A
small shot of raw fuel (from a squirt can) injected directly into
the air intake can help. If the engine fires on that small shot
of fuel but keeps running and won’t start without it, then it’s a
pretty safe bet that the fuel system’s the problem.;gehj]kkagf2 Now we’re getting into fairly involved engine
problems. If you’ve ruled out electrical, spark/ignition and fuel
problems but the engine still won’t start, it may have an internal
problem such as low compression. A compression gauge is
relatively inexpensive and available at any auto parts store.
Generally, most engines will show cranking compression of at
least 85 to well over 100 psi. If yours is below that or one or
more cylinders is more than 15 percent lower than the others,
your engine may simply have a blown/bad head gasket (tighten
the cylinder head to check)—or it could have internal damage
and should be checked by a technician.=p`Ymkl2This is the least common problem, but hey—it’s
an outboard, and anything can happen. An engine may have
the right fuel/air mix, the right spark at the right time, great
compression, but if it can’t exhaust the burnt fuel/air mixture,
it won’t start or run. As a last resort, check the exhaust outlets
for blockage. We’ve seen outboards stored for winter and during
spring startup, large mouse/rodent nests built over the winter
cause exhaust blockage significant enough to keep the engine
from starting. You never know!This guide is to help you pinpoint problems at the dock or
launch ramp, with minimal tools, and in a short amount of time.
It’s by no means a complete troubleshooting guide for starting
problems. For that, your best bet is to purchase a factory service
manual for your year/make/model engine. These manuals are
designed for technicians so the information may be hard to
follow and understand, but they can be a great aid in helping
you diagnose and fix problems with your engine, if you’re
mechanically inclined and have the temperament to do so. If
you do—happy wrenching!