Fuel pump constantly running

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little poping is ok. you can try and open a/f screw 1/4 turn. but now tou mention issue with cyl 4. think that neds ti be resolved first and might start fixing your issue with pump. is it flooding and mking plug wetter then others at idle..swap coil ht leads plug etc see if issue stays in cyl or follows
 
Looks like the time is a little off on these posts. Must be something with moving the site. Yeah, I hooked all 4 up and the pump seems fine. Not sure what's going on, maybe the clamp wasn't tight enough going from the pump to the carbs? What is up with that weird clamp anyway? Can't a regular clamp fit there?
The clamp on that vent line is a major p.i.a. I replaced it with a hose clamp and lengthened the hose a little when I installed the TEE for the oil cap venting system. Easy on easy off now. I remove the over flow tank and stick a long screw driver in or a 1/4 drive extention with a 5/16 socket, and easy peesy.
 
I know all of the coils are fine, I just installed COPs from Gannon. I have tried swapping them around. I would think if cylinder 4 was being flooded with fuel there would have to be smoke coming out of the exhaust. It's almost like the idle circuit is plugged on carb 4, but it has been disassembled and cleaned twice! Could there be something going on with the mixture screw? I have no idea. Yes, the bike does backfire way too much. Also, it seems that the bike runs on all 4 cylinders when you are above the idle circuit.
 
Well I am still having the issue with the bike idling only on carbs 1 & 2.

Tonight I turned the mixture screws all the way in on carbs 1 & 2, left 3 & 4 open, turned on the choke and the bike fired right up running on 3 & 4. I let the bike warm up, turned off the choke and the bike actually stayed running, but it only ran for a few seconds before it quit. It runs much better off carbs 1 & 2. I took all of the jet blocks out yesterday and verified that the pilot jets were definitely not plugged up and they were clean.

The only other thing I am leaning toward is a possible electrical issue. I just installed a brand new Odyssey PC 680 about a month ago and with the bike idling at 1000 rpm I am getting 13.05 volts across the terminals which according to the electrical troubleshooting guide here on this site, that is marginal. Could this be causing my issue? The bike definitely runs on all 4 cylinders above the idle circuit. Also, have new COPs installed and I know they are all firing.

So I'm thinking it's something with the charging system or the idle circuits are still plugged on those 2 carbs.
 
And you got gap set lower then stock....
How about vacuume leak potential from carb joints...
 
Yes, the gap is correct per the instructions that came with the cops. Joints all look good, and I've sprayed carb cleaner around them to verify.
 
I forget where u have your carbs set up at but i've dropped the needle a clip usually to help that issue. its in the translation point onto mext circuit.
 
The clamp on that vent line is a major p.i.a. I replaced it with a hose clamp and lengthened the hose a little when I installed the TEE for the oil cap venting system. Easy on easy off now. I remove the over flow tank and stick a long screw driver in or a 1/4 drive extention with a 5/16 socket, and easy peesy.

Plus 1 on the vent line, also check to see if the gas tank vent on top is clog to.
 
The vent line is clear. Fuel pump has been replaced. All of the fuel line from the tank to the carbs is new. The plugs are new. Changed to COPs and they are all firing. Plugs are gapped to the specs that came with the COP install instructions. Voltage at idle is 13.05 which does seem a bit low, but should be sufficient for the bike to idle correctly. Battery is a month old (Odyssey PC 680)

Here is the issue again:

Well I am still having the issue with the bike idling only on carbs 1 & 2.

Tonight I turned the mixture screws all the way in on carbs 1 & 2, left 3 & 4 open, turned on the choke and the bike fired right up running on 3 & 4. I let the bike warm up, turned off the choke and the bike actually stayed running, but it only ran for a few seconds before it quit. It runs much better off carbs 1 & 2. I took all of the jet blocks out yesterday and verified that the pilot jets were definitely not plugged up and they were clean.

So I'm thinking it's something with the charging system or the idle circuits are still plugged on those 2 carbs.
 
Can you dangle the two spark plugs from the non-running cylinders, and ground them to the chassis, to visually verify you have good, solid spark in those two cylinders? (not sure that works w/c.o.p.s.)
 
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