The two plastic screens on either side of the bottom of the gear case
of your outboard engine actually serve two purposes. First, water from
whatever you?re floating in enters through them and gets pumped through
the engine for cooling purposes. Second, the screens keep larger
objects from being sucked in and blocking internal cooling passages.
larger objects from being sucked in and blocking internal cooling
passages.


But because the screens have small holes, they can become clogged,
especially when boating in shallow water, muddy flats or grassy areas.
Trying to rock your boat off a sandbar is almost a sure way to clog
these ports. It?s easy to tell when they become clogged because the
little telltale nozzle on the back of your outboard engine ? you know,
the one that squirts a stream of water ?ceases to flow. It?s a simple
fix, really. Here?s what to do.

1 If you notice the water flow stop, cut the engine immediately, turn
it all the way to starboard and trim it up and out of the water.
2 Take a screwdriver, which should be in your onboard tool kit (see
Oct. 1998, pg. 20) and remove the retaining screw on the port side of
engine. You must remove both screws before they will pull out. Turn the
engine full to port and remove the screw from the starboard side. At
this point, the screens on both sides are loose and will pull out of
their slots.
3 With both screens out, clear any weeds, mud or sand that are causing
the blockage. It sometimes helps to lower the engine back into the
water to help flush out the port a bit (provide you?re not in the same
muddy, sandywater).
4 Once you?ve cleared the obstruction, flush the screens in the water
to remove any debris from them.
5 Reinstall the screens, making the screws just hand tight and lower
the drive back into the water.
6 Wait a few seconds, start the engine and closely watch the telltale
nozzle, which should begin to squirt water again in five seconds or
less.

Best regards
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