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Old 05-27-2008, 11:46 PM   #1
69halfton
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running funny.

fired up the 383, and drive it maybe 5 min when it just up and wuit. towed it home, by the time i got back, it just fired right up again. ran another 5 min, then it quit again.

its running again, (after another cool-down), but if i put in any kind of throttle, other then what is needed, the truck stalls, then pulls, then stall, then pulls, but real fast.

i asked dad, he said it sounds like a coil problem, but wouldn't that only account for the shutting off, not the stalling, then pulling again over and over?
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Old 05-28-2008, 03:40 AM   #2
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Re: running funny.

oh, its an HEI dizzy
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Old 05-29-2008, 04:23 AM   #3
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Re: running funny.

ttt
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Old 05-29-2008, 04:57 AM   #4
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Re: running funny.

Jason,

If I had to guess, I would say it's a fuel problem. Does the truck have a fuel filter on it besides the one in the carb? (I would check it) If it has a separate one I would change it. There is also a cloth sock on the fuel tank pickup tube (some times it's rotted off) that can get clogged up. I could be way off but it sounds like it is picking some junk up and restricting the fuel flow.... Could also be the fuel pump.

Just some things to look at that don't cost a lot...

Maybe some other guys will post up with more ideas.

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Old 05-29-2008, 05:04 AM   #5
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Re: running funny.

I would also say it might be the fuel pump. I just had to replace mine because when i gave it a lot of throttle it would pull hard and stall. It also ran gas out of the pump though when I shut the truck off. I don't know what would cause it to shut off though.
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Old 05-29-2008, 06:01 AM   #6
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Re: running funny.

You might need to also check all the rubber hoses on the fuel line.

I had a similar problem and it turned out to be that the rubber hose on the suction side of the fuel pump was collapsing.

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Old 05-29-2008, 04:43 PM   #7
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Re: running funny.

Could also be a bad float in the carb. Brass floats can crack and fill with fuel, causing it to "float" lower in the bowl. This will cause it to do just what you described. Lower float means less fuel in the bowl, meaning the bowl runs empty when you hit the gas. As always check the easy stuff first, like everyone else said. Filters, screens, rubber lines. If you find nothing, check the float.
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Old 05-29-2008, 05:59 PM   #8
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Re: running funny.

I'd agree with Joedoozer; first check is the float level. If it idles OK but dies with any throttle, I'd bet on the fuel bowl in the carb going empty with demand.
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Old 05-29-2008, 06:29 PM   #9
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Re: running funny.

Great replies, deffinatley fuel issue.

Eric
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Old 05-30-2008, 03:59 PM   #10
69halfton
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Re: running funny.

Just letting you know, i took the distributer all aprt, since i wasn't getting any replies here yet, and It was bugging me. once i got the rotor off, and pulled out that little black box thing (i belive its called the modulator?) i found that it was COOKING hot. I asked some buddies about it, and they all said it was the modulator. bought a new one, slammed it in, and the truck runs better then it ever has!

coils and things sometimes do very strange things. Just letting you guys know in case you ever experience this problem.
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Favorite caption:

first car to 200 mph in the 1/4 mile, no parachute, drum brakes all the way around..
..back when men were men.
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Old 05-30-2008, 08:47 PM   #11
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Re: running funny.

Did you goop it up good with the dielectric grease they give ya? That will help draw heat out.
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Old 05-30-2008, 11:05 PM   #12
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Re: running funny.

Quote:
Originally Posted by 69halfton View Post
Just letting you know, i took the distributer all aprt, since i wasn't getting any replies here yet, and It was bugging me. once i got the rotor off, and pulled out that little black box thing (i belive its called the modulator?) i found that it was COOKING hot. I asked some buddies about it, and they all said it was the modulator. bought a new one, slammed it in, and the truck runs better then it ever has!

coils and things sometimes do very strange things. Just letting you guys know in case you ever experience this problem.
Glad you got it figured out.

Eric
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Old 05-30-2008, 11:17 PM   #13
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Re: running funny.

Thank you for the follup post letting us know that you found the problem and it is now fixed.

Danny
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Old 05-30-2008, 11:46 PM   #14
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Re: running funny.

hey 69 halfton, I had a problem like that years ago with my Mallory ignition. I replaced the module twice in a year before I realize I had a bad ground between the battery and the engine. Thats what was causing the unit to get over heated. I would check out all your grounds just as a precaution.
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