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Offline Gunslinger

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Running rough
« on: March 16, 2014, 05:45:00 PM »
Just got out of the jeep, It's about 25 F here today. Jeeps been sitting for a week, started it up and drove to the grocery store, it came up to temp and ran fine.  I did have to choke it to start as usual.  Store is five miles away, engine came to temp,and we parked and shopped for about thirty minutes.  When we came out I started it and it ran rough until I choked it, maybe a quarter choke, ran it like that for five minutes, took it off choke and it ran fine all the way home.

It does this in the summer as well.  If I don't choke it it will die, but it only acts like that after a drive, and only for five minutes after restarting.   I've' installed the shield that goes over the exhaust manifold to deflect heat away from the carb thinking that when it was sitting the gas was boiling out of the carb, but that doesn't seem to be the culprit, any thoughts guys?

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Offline p3ferris

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Re: Running rough
« Reply #1 on: March 16, 2014, 06:29:44 PM »
Did the dist. get wet with snow?
Summer  is a puzzler

Offline garage gnome

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Re: Running rough
« Reply #2 on: March 16, 2014, 06:32:21 PM »
Check the cap for corrosion.
Nate in Western MA 1953 3A #3268, The Jalopy, '47 2A Wheelin' rig, '49 3A, #37071, unmolested, bone stock named Ted

Offline Gunslinger

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Re: Running rough
« Reply #3 on: March 16, 2014, 07:14:13 PM »
P3
It's a dry cold day today, no water on the roads, no melting.

Gg
I'll check the cap, but if it was corrosion wouldn't it run like that all the time? 

My spidey senses want to point me towards a fuel problem in the carb, but I've messes with the jets to no avail..
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Offline garage gnome

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Re: Running rough
« Reply #4 on: March 16, 2014, 07:17:15 PM »
Ted had corrosion on the cap before he was Ted and it made the engine act really strange.
Nate in Western MA 1953 3A #3268, The Jalopy, '47 2A Wheelin' rig, '49 3A, #37071, unmolested, bone stock named Ted

Offline 1955CJ-5

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Re: Running rough
« Reply #5 on: March 16, 2014, 07:37:47 PM »
It does sound a little like fuel flow/vapor lock or something similar...is it plumbed like the original or do you have an extra in line fuel filter...?

And one other thought.....could the fuel line be routed too close to the exhaust pipe under the jeep, where the fuel line exits the tank?
« Last Edit: March 16, 2014, 08:22:59 PM by 1955CJ-5 »
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Offline p3ferris

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Re: Running rough
« Reply #6 on: March 17, 2014, 07:12:36 AM »
Vapor lock is easy to check.  Wrap the fuel lines with a generous amount of tin foil.  That will soak up the heat.  Then drive like you normally do when haveing the problem.  If problem still exists, it is not vapor lock.

Offline Oilleaker1

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Re: Running rough
« Reply #7 on: March 17, 2014, 07:40:30 AM »
Fuel delivery pressure to the carb? All stock? Electric pump? Solex or Carter? If it is leaking by the inlet primary needle and seat, you will be flooded for a while. Black spark plugs from being too rich? Dry and light colored plugs would be just the opposite----too lean, not enough fuel. The biggie clue is whenever you need choke to run, you are either lean, or have a vacuum leak. Base of carb, too tight of valve clearances, loose vacuum wiper hoses.  Regor over on the 2A page found that he had knocked his wiper hose off and didn't notice it. Simple test is plug off the wiper vacuum port on the manifold and eliminate that. John

Offline scoutpilot

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Re: Running rough
« Reply #8 on: March 17, 2014, 12:09:35 PM »
[size=14]Based solely on the description you've given I would have to suspect slow flooding. Either the needle and seat are dirty, or you're experiencing excess fuel pressure after stopping. The next time you run it up to temp, shut it down and look down the throat to see how much fuel accumulates in the barrel. One other thing it could be is a worn float pin.[/size][/b]
« Last Edit: March 17, 2014, 12:10:34 PM by scoutpilot »
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Offline Gunslinger

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Re: Running rough
« Reply #9 on: March 17, 2014, 07:41:57 PM »
Thanks to you all for the advice, checked the dist cap, no corrosion, however, I did revisit the in line fuel filter.  It was about 3 inches from the exhaust pipe.  It was time for a change so I bought a new one, and moved it rearward so it now sits behind the steering box with just a rubber line to the pump.  Took it for a drive, shut down for about 10-15 while I gassed up, started up and ran like a top, I'm declaring this one solved.  Repeated the process when I got home, same result  :).  Thanks again gents. :D
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Offline p3ferris

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Re: Running rough
« Reply #10 on: March 17, 2014, 08:19:43 PM »
Glad you have it fixed  Happy jeeping

Offline Oilleaker1

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Re: Running rough
« Reply #11 on: March 18, 2014, 08:02:08 AM »
Sounds like you are ready for Memorial Day! ;) John