Buggies Gone Wild Golf Cart Forum - View Single Post - Workhorse and MPT...I have my work cut out for me

JPonLKN · 10-28-2020, 11:09 AM

That is what I was wondering...and makes perfect sense to the symptoms (backfiring through the carb) that they reported. Something causes the timing of fire to be out of wack. Do you know what component off the motor would cause the timing to be off? If everything on the engine is pre-mci, flywheel, pulsar, ignitor, and coil, the firing timing should be controlled on the engine, correct? Does it receive any signal from inside the cart wiring harness? See that black box in the photo above.

The coils are different between MCI and Pre-MCI, different shape entirely, and the coil on this engine is a Pre-MCI coil, matches exactly with my older TXT coil. I have an MCI coil on one of the spare engines. I'm not looking at it now, but I think wire colors changed as well. I also found that the flywheel changed and the pre-MCI flywheel has a keyway, while the MCI flywheel does not. I am pretty sure the engine was re-built correctly as a pre-MCI engine with correct flywheel, pulsar, ignitor, and coil; however, nothing was done to the MCI cart wiring. Not sure what that black box is with all the wires going into are in my last post...the solenoid behind is simply a switch, so it shouldn't matter.

I have a pre-mci wire loom from my pre-MCI TXT that I converted to the 670 big block that is available, but was hoping to use that for the workhorse project if I needed it. Only have one MCI engine and I think both carts originally had MCI engines in them. Looks like I will be doing the engine swap and putting the MCI engine in this MPT and rewiring the workhorse when I put this motor in it.

How can i tell if the wiring loom is Pre-MCI or MCI? What are the tell tale signs?

10-28-2020, 11:09 AM	#16
JPonLKN Gone Wild Join Date: Jul 2020 Location: NC Posts: 773	Re: Workhorse and MPT...I have my work cut out for me That is what I was wondering...and makes perfect sense to the symptoms (backfiring through the carb) that they reported. Something causes the timing of fire to be out of wack. Do you know what component off the motor would cause the timing to be off? If everything on the engine is pre-mci, flywheel, pulsar, ignitor, and coil, the firing timing should be controlled on the engine, correct? Does it receive any signal from inside the cart wiring harness? See that black box in the photo above. The coils are different between MCI and Pre-MCI, different shape entirely, and the coil on this engine is a Pre-MCI coil, matches exactly with my older TXT coil. I have an MCI coil on one of the spare engines. I'm not looking at it now, but I think wire colors changed as well. I also found that the flywheel changed and the pre-MCI flywheel has a keyway, while the MCI flywheel does not. I am pretty sure the engine was re-built correctly as a pre-MCI engine with correct flywheel, pulsar, ignitor, and coil; however, nothing was done to the MCI cart wiring. Not sure what that black box is with all the wires going into are in my last post...the solenoid behind is simply a switch, so it shouldn't matter. I have a pre-mci wire loom from my pre-MCI TXT that I converted to the 670 big block that is available, but was hoping to use that for the workhorse project if I needed it. Only have one MCI engine and I think both carts originally had MCI engines in them. Looks like I will be doing the engine swap and putting the MCI engine in this MPT and rewiring the workhorse when I put this motor in it. How can i tell if the wiring loom is Pre-MCI or MCI? What are the tell tale signs?