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Unread 10-06-2013, 09:43 AM   #16
Matt1981CJ7
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The standard setup is to have the wix-type bypass filter between the carb and a mechanical pump.

I'm not sure what the best setup is for an electrical pump, but I suspect you may be loosing too much pressure under load by having the bypass filter so far from the carb. The fuel will take the path of least resistance, which may be the return line in your current setup.

Matt

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Unread 10-06-2013, 10:42 AM   #17
stephenspann27
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My setup doesn't have a return line. I can watch the fuel flow through the glass filter by the carb. Before replacing the clogged filter the glass one would barely stay half full. With that problem corrected the glass filter is always full even at high rpm.
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Unread 10-06-2013, 10:44 AM   #18
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I am starting to wonder if I have a bent pushrod or burned valve. If a new plug wires and icm don't fix the issue ill do a compression test and pull the valve covers
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Unread 10-06-2013, 10:53 AM   #19
LumpyGrits
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That filter by it's design, regulates psi.
The smaller outlet port(return line)must be installed at the 12 o'clock position.
I would also check to see if you have the carb float set 'rite'.
Make sure your carb is 'rite' BEFORE you start throw'n $$$ at it..........
LG
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Unread 10-06-2013, 11:46 AM   #20
stephenspann27
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All measurements aside, the float is basically supposed to be level when the needs seats correct? I'll get another wix filter and get it back in place.
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Unread 10-06-2013, 04:55 PM   #21
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ok.. so I went wheeling.. for about 4 hours. I replaced the wix filter. Something is definitely up with the fuel delivery. I am back down to 1.5 psi. I'll find a replacement pump and go form there. It seems to obviously not be getting enough fuel.. surges on the hwy.. it will idle.. but not run under a load.
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Unread 10-07-2013, 10:39 PM   #22
stephenspann27
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Replaced the pump today. Definitely not a fuel supply problem. Pressure is good. I also took the top off the carb to find the bowl full. With the key on (pump running) if I press down on the float, fuel comes flying out. A guy on another forum somewhat has me convinced it's a stretched timing chain.. that would explain the timing mark that seems to be off. Before looking into that, I want to replace the power valve. I know mine is dual stage. Does anyone know what the specs are on the stock valve? Or should I drive it with a vacuum gauge attached and try to get a cruise reading?
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Unread 10-08-2013, 06:08 AM   #23
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Sounds like you need to do some basic troubleshooting: I would start with a compression test, this would eliminate a suspect burnt valve. The timing chain is a good bet, but it could also be a worn out camshaft bent pushrod,weak lifter. Are you shure that there isn't a crossed plug wire, or a crack in the distributor cap? Check the resistance of the plug wires. There is a posibility that it isn't a fuel problem afterall. Good luck!
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Unread 10-08-2013, 12:48 PM   #24
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Are you running the stock prestolite ign or has it been changed?
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Unread 10-08-2013, 07:54 PM   #25
stephenspann27
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Quote:
Originally Posted by Scoutski View Post
Sounds like you need to do some basic troubleshooting: I would start with a compression test, this would eliminate a suspect burnt valve. The timing chain is a good bet, but it could also be a worn out camshaft bent pushrod,weak lifter. Are you shure that there isn't a crossed plug wire, or a crack in the distributor cap? Check the resistance of the plug wires. There is a posibility that it isn't a fuel problem afterall. Good luck!
I agree. I have new wires arriving tomorrow. It still have the motorcraft ignition. The cab looks newish, I replaced the coil, rotor looks good. But ya.. I haven't ruled out much so far.
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Unread 10-08-2013, 08:31 PM   #26
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I verified that the spark plugs are wired correctly. I will be posting a video in the next few minutes of me rotating the crank and watching the rotor. I would have to turn the crank 90 degrees before the rotor ever moved.
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Unread 10-08-2013, 08:47 PM   #27
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It's hard to see how far I'm moving the crank. I'm going from 12 o click to 3 o clock before the rotor moves any. I wouldn't think this is normal? If it's not the chain maybe it's a worn distributor gear?

https://www.dropbox.com/s/pei0qtm070...008_212642.mp4
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Unread 10-08-2013, 09:48 PM   #28
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I know I'm just jumping in here, but the rotor should turn half of what the crank does. It takes 720 degrees of crank rotation for the rotor to turn 360.
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Unread 10-08-2013, 09:55 PM   #29
stephenspann27
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Quote:
Originally Posted by MoneypitCJ5 View Post
I know I'm just jumping in here, but the rotor should turn half of what the crank does. It takes 720 degrees of crank rotation for the rotor to turn 360.
I hear ya.. but I get zero movement out of the thing when I change directions until I've turned the crank almost 90 degrees. I think I need to pull the dist. and check the teeth.
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Unread 10-08-2013, 10:22 PM   #30
MoneypitCJ5
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If you want to know for sure, turn the crank 180. The distributor should move 90. I'd say if that's not happening you've got a problem.

When you change directions you move the slack side of the chain and it moves more than you'd expect.
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