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Discussion Starter #1
Having some small issues trying to get the motor fired up.

Motor fires cleanly on the internal mag trigger

Unplug the internal mag trigger and hook the white points wire to the purple wire on the mag(does the green wire need to be grounded?)

Motor tries to fire but cuts out

timing seems very erratic
RPMs show 11000
bs3 sensors seem to be erratic
I've got the crank trigger grounded to the heads with the ground for the coil
 

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The crank trigger wires need to go direct to the ecu, there are no extra grounds except for the shielding ground of the MWH. Points wire goes to violet on the generator as you have, and the green wire is left unterminated. Generator connects to points box, and the points box connects to the coil with an extra ground. Most issues with the mag stuff starting is related to cranking speed and/or phasing of the trigger on the generator. Other thing that sometimes helps is a capacitor on the ecu power leads. Also, make sure the heads are grounded well to battery/chassis to give the spark a clean path and your headgaskets will thank you! That's where I would be digging first...
 

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Discussion Starter #3 (Edited)
The crank trigger wires need to go direct to the ecu, there are no extra grounds except for the shielding ground of the MWH. Points wire goes to violet on the generator as you have, and the green wire is left unterminated. Generator connects to points box, and the points box connects to the coil with an extra ground. Most issues with the mag stuff starting is related to cranking speed and/or phasing of the trigger on the generator. Other thing that sometimes helps is a capacitor on the ecu power leads. Also, make sure the heads are grounded well to battery/chassis to give the spark a clean path and your headgaskets will thank you! That's where I would be digging first...

Thanks, I got some good advice from Moran and Collins.

1st problem, I setup everything up with the rotor on #1 at 20 degrees, once I fired it up the timing was at 5 degrees BTDC so I turned the mag and got the timing at 20 degrees BTDC.

BUT that moved the rotor so the trailing edge was 1/8" past #1 terminal. Tried to rotate the cap but not enough movement.

So, I turned the mag 1/8 turn and moved all the plug wires so they were on the right terminal. Fired it up, timing was at 30 degrees BTDC, turned it back to 25 and locked it down. Now the cap can be rotated so the rotor is phased so the rotor tip leading edge is on #1.

So now the rotor and internal trigger are phased properly.

Next things to check.
Grounds - move the ground on the MWH
check the air gap on crank trigger(RPMs are spiking while cranking)
ground the points box case

Mike Moran said that 20 degrees BTDC advance and the rotor phasing behing past the terminal would cause some weird shit.

Its got a 1 ga wire from the battery to the motor plate and from there a bunch of #10 ground wires come off. Both heads tie together with a #10, passenger head has a 10 to the coil and 10 to the chassis.
 

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when i used the promag, i plugged the mag into itself, phased the mag so that the rotor was leading edge of #1 on cap. check timing (we used 22 deg) ..... unplug the mag, plug into a wire coming from the ecu. then the ecu will contol timing.

make sure you have the ref/sync sensors setup configured properly. it sounds like you need some help getting it all setup.

try locking the timing on the ecu and see what it reads on the crank.
 

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Discussion Starter #5
problem was the bs3 was getting a dirty signal to the pink ignition wire. Once I fixed that, all the problems went away.
 

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