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Old 07-05-2016, 06:23 AM
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BunnyPlanet169 BunnyPlanet169 is offline
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Quote:
Originally Posted by hanleyclifford View Post
If you are running both ignition and fuel pump thru a 5 amp fuse you are taxing that fuse. Ignition be from 1 to 4 amps, typically, and the pump may want 3 or 4 amps. I like to see ignition on an independent circuit for this and other reasons.
Careful. For safety, it makes sense to only power the fuel pump when the ignition is on. For this reason, it's usually powered off coil+. This, plus the OPSS, prevents an energized pump except for when the engine is running.

If the fuse is between coil + and the fuel pump, it's only going to see the load in that branch circuit. It will not see the coil, or E.I., or alternator excite which are also usually powered from coil +.

IIRC the pump draws about 2A, and a 5A fuse comes standard with the MMI kit.

The MMI wiring diagram shows a 20A fuse and a 12AWG wire from the ignition terminal on the starting switch and coil+. Your install may be different, but the 5A fuse in the fuel pump branch circuit is appropriate for these conditions.

http://www.moyermarine.com/forums/sh...ring+schematic
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