Engine swap question
 

I am changing out a 2000 7.4 MPI for a 2007 496 Mag HO. Seems pretty much plug and play but there are a few differences with the wiring. The new motor has the standard 9 pin main connector for the harness and that should be fine for all analog gauges. The issue is that on my old motor I had a breaker switch attached to one of the risers and there is an extra red wire that run along the main harness that attached to that breaker. Now on the new engine there is still a breaker but it is internally wired thru the motor (I guess thru computer) so what to do with this extra red wire coming from the helm... Also, I had a wire running from my battery switch to the mercathode and now on the new motor the wiring for the mercathode is all internal as well (besides the two wires that come up from the drive). Any ideas on what to do with extra wires? Do I no longer need them?.... will she run without them? Haven't installed motor yet... just getting prepared for some road blocks. Electrical is my weakness.

Thanks for any help.


Brian

I think the red wire on the 7.4 is coming from the starter fuse to the 50 amp breaker ?? or I may not be reading this correctly

Yes.... that's one that the 496 doesn't have. The other is a line from battery witch to Mercathode... it's a fused link (purple and orange wire I believe) and I have had it go on me and when it does there was no power to the ignition on the 7.4. Just wondering if all will be good if I just eliminate these two wires.

Thanks