New motor backfiring through carb

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And if you can't find directions;
the slot on the pumpdrive should be pointing to the driver's side frontmost intake bolt, with the #1 piston (driver's side front), at TDC on her compression stroke.
Sometimes the drive will not go all the way down into the pump because of the hex phasing. Then you have to rotate the crank a few degrees until it drops down. Then reestablish TDC compression and check the slot orientation. Sometimes it takes several tries.
Alternatively, you can pull the I-drive back out, and drop your priming tool back down in there, and rotate the pump a few degrees, and start over. Don't forget, the I-drive spirals down into position, and you have to start into it somewhere around 1/4 turn CCW from where you want to end up at. I set the drive down on the cam, push down with a big screwdriver,and turn CCW about 3 clicks, I can't remember exactically.
Sometimes it is a PITA.
Then after all that, you can finally drop the D in there with the rotor pointing somewhere in the vicinity of the tower that is marked #1 on your cap. If you don't have such a cap just point the rotor in the general direction of the rad, drop it in and rotate the driveshaft CW until it drops into the slot.
Next,install the hold-down clamp just snug enough that you can still rotate it.
Next push the Vcan all the way to the firewall.
Next rotate the crank to align the timing marks at around 10 to 15 degrees advanced.
Next, rotate the D until the nearest vane lines up with the center of the pick up.
Next take a Sharpie and mark the outside of the housing to indicate where the rotor is.
Next drop the cap into position and make sure there is a tower on top of the rotor. If there is, Sharpie that tower and mark it #1
Next install your wires according to the firing order with the marked tower being #1.
OK ready set crank it!
Finally, put a timing lite on it, and set the all-in power-timing to no more than 34/36, secure the clamp, and let the tuning begin.
 
And if you can't find directions;
the slot on the pumpdrive should be pointing to the driver's side frontmost intake bolt, with the #1 piston (driver's side front), at TDC on her compression stroke.
Sometimes the drive will not go all the way down into the pump because of the hex phasing. Then you have to rotate the crank a few degrees until it drops down. Then reestablish TDC compression and check the slot orientation. Sometimes it takes several tries.
Alternatively, you can pull the I-drive back out, and drop your priming tool back down in there, and rotate the pump a few degrees, and start over. Don't forget, the I-drive spirals down into position, and you have to start into it somewhere around 1/4 turn CCW from where you want to end up at. I set the drive down on the cam, push down with a big screwdriver,and turn CCW about 3 clicks, I can't remember exactically.
Sometimes it is a PITA.
Then after all that, you can finally drop the D in there with the rotor pointing somewhere in the vicinity of the tower that is marked #1 on your cap. If you don't have such a cap just point the rotor in the general direction of the rad, drop it in and rotate the driveshaft CW until it drops into the slot.
Next,install the hold-down clamp just snug enough that you can still rotate it.
Next push the Vcan all the way to the firewall.
Next rotate the crank to align the timing marks at around 10 to 15 degrees advanced.
Next, rotate the D until the nearest vane lines up with the center of the pick up.
Next take a Sharpie and mark the outside of the housing to indicate where the rotor is.
Next drop the cap into position and make sure there is a tower on top of the rotor. If there is, Sharpie that tower and mark it #1
Next install your wires according to the firing order with the marked tower being #1.
OK ready set crank it!
Finally, put a timing lite on it, and set the all-in power-timing to no more than 34/36, secure the clamp, and let the tuning begin.

Got it running yesterday without any issues.
 
So what was the problem?

Out of time. Went to reset it and the harmonic balancer was marked wrong. Got it close enough and it fired on the first crank. Engine didn’t even turn over once before It fired. I still got some things to button up but it was a good feeling.
 
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Out of time. Went to reset it and the harmonic balancer was marked wrong. Got it close enough and it fired on the first crank. Engine didn’t even turn over once before I fired. I still got some things to bottom up but it was a good feeling.
good deal, glad u have it figured out
 
Your marks can still line up and you be 180 off, since you pulled and primed since dyno and made no other changes...…. Pull and spin 180 and see.
 
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