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Old 08-06-2004, 04:13 PM   #1
jorgensensc
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Carb problems. Help.

I recently did a total tunup on my truck because the wires were burnt from the manifolds. I had a deiseling problem develop before I did all the work and I figured this would help fix it. Needless to say it didn't. I'm soo frustrated since I can't seem to dial this thing in right. It's a 350 with an edelbrock RPM Air Gap intake and a edelbrock 1406 600cfm carb. I replaced the wires with all new good ones and plugs, fuel filter,exhaust manifold gaskets, etc. I have even been trying to adjusting the carb without any luck. I set the timing to 8 degrees BTDC. At a stoplight if you mash the gas it will sputter and cough, and even sometimes die. Even sometimes if you lightly press the gas it will die out. Not all the time, but sometimes. When I first start driving(whether the truck is at operating temp or not) it will backfire once through the carb, but doesn't do it again after the first time. When I go to turn it off it wants to diesel sometimes, not all the time, but sometimes. And it is usually one of those long ass ones that you think will never end. The truck runs great when above idle and on the road. Performs great with no hesitation at all. Please help me figure out this problem I am getting so frustrated, not to mentioned embarassed when my beautiful truck stalls in the middle of an intersection coming off a light or starts deiseling in front of a store.Thanks to all the advice and help in advance.
Shawn
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Old 08-06-2004, 04:43 PM   #2
HuggerCST
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Most of the time, as you probably know, dieseling is caused by either timing, or idling too high. Make sure you check the timing with the vac. line unhooked and plugged at the dist, and also make sure it is idled down to around 600 rpm. 2nd check for vacuum leaks around the carb area, as that could cause those symptoms. I'm not too familiar with that carb, but my guess is that you will find a vacuum leak somewhere, maybe even internal.
EDIT: Also, check your vac. advance. And to stop the dieseling untill you find the problem, kill it while it's in gear.
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Old 08-06-2004, 05:19 PM   #3
68 Suburban
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I was having the same type of problem 4 years agon and I was blaming the carb. It turned out to be the distributor was warn and had a fluctuating timing problem. I switch the regular distributor and have not had the problem since.

As for the dieseling, I have heard that can be caused by carbon build up in the chambers and when the engine gets hot enough, you have the dieseling run on problem.

Also, I don't know what your engine set up is, but if it is close to stock, I found the 1406 carb needed to be tuned down two steps. Out of the box, it was way to rich for my engine. The good thing is, once you get the tuning kit, the carb is easy to tune.

The carb out of the box is at the 1 position, I have mine set a the 14 position.
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Old 08-06-2004, 06:15 PM   #4
jorgensensc
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Thanks for the suggestions so far guys, I am going to go mess with for a little bit tonight.
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-What would you attempt to achieve if you knew you could not fail?-

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Old 08-06-2004, 07:45 PM   #5
71swb4x4
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Sounds like you finally have your reason to go TPI
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Old 08-06-2004, 08:25 PM   #6
jorgensensc
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I know I know. TPI sooner or later, but then I want a new overdrive tranny, then rear end, it never stops
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1972 C20 Suburban- Big Blue Betty
'56 Chevy Bel Air Sedan- Frame up Restoration

-What would you attempt to achieve if you knew you could not fail?-

-I Refuse To Tiptoe Through Life, Only To Arrive Safely At Death's Door-

R.I.P. EAST SIDE LOW LIFE
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