350 keeps dieseling

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Irishman999

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You are sure you dont have a vacuum leak?
 

crazy4offroad

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so i put my carb back to factory settings and the dieseling is not as frequent and my sputtering is faint but still there?? when i tried tuning my idling screws when i leaned them all the way out i had a stronger idle so now im back to square one??

I dont know what you mean by "leaned them out all the way" does this mean you screwed them clockwise all the way in till they stopped? If so it sounds like the carb is running rich on idle, which tells me the idle circuit is probably plugged. If you dont have a fuel filter on the fuel line coming into the carb GET ONE or you'll be doing this from now on. Take the top off the carb and apply compressed air to the primary jets. This will clear the idle circuits of dirt. The idle circuits draw air and if they're clogged they will get more fuel than needed. If this dont help you'll need to set your float levels. Page 8 and 9 will show you how, here: http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf
 

82chevy350

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Everybody's entitled to their own opinion on this but in my opinion you couldn't be further from wrong. My 1406 has been great to me for many years, and a lot easier to work on than q-jet/holleys.

I agree they are very easy to work on and pretty responsive
 

Swims350

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edelbrock carbs are the best. easiest to work on and most reliable.

Now with that said which way are you thinking you leaned it out? did you turn the screws in or out?

on and edelbrock IN is leaner. and out is richer.

I also read somewhere if turning them All the way IN doesn't make it try and stumble the carb is too big for the setup it's on.
 
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crazy4offroad

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I also read somewhere if turning them All the way IN doesn't make it try and stumble the carb is too big for the setup it's on.
A 600 cfm on a 350 is just right, I'm still sticking with dirt in the idle circuit, floats out of adjustment, or worst case scenario, I'm wondering if burnt exhaust valve(s) could cause it.
 

Jims86

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:wave:
A 600 cfm on a 350 is just right, I'm still sticking with dirt in the idle circuit, floats out of adjustment, or worst case scenario, I'm wondering if burnt exhaust valve(s) could cause it.
^^^x2
A vacuum gauge would be helpful in both tuning and diagnosing any bad valves.
 

Swims350

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I have my doubts on burnt valves now testing with a vac. gauge.

My brother in laws ford had a bad burnt valve on the number 6 cylinder and the vac. gauge read steady and strong, however it is a fuel injected motor, I don't think you can test fi with vac. gauge can ya?
 

Jims86

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I have my doubts on burnt valves now testing with a vac. gauge.

My brother in laws ford had a bad burnt valve on the number 6 cylinder and the vac. gauge read steady and strong, however it is a fuel injected motor, I don't think you can test fi with vac. gauge can ya?

He's running an Eddy carb. he could als do a compression check.
 

crazy4offroad

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A compression check might do better at showing compression loss due to exhaust valves, since it would be going straight out the exhaust. Burnt intake valves would definately show a shaky needle on a vacuum gauge since the compression would be going back into the crankcase.
 

ccmf22

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i turned my screws in clock wise and it ran better and now that i think of it i did clean out a lot of sand from my bowls (i did have a filter.. it was just not filtering enough, may need more than just an inline) well ill take the top half apart and blow air threw my primary jet holes, well see how it goes.
 

crazy4offroad

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If you have one of those glass "cleanable" filters they let a lot of crap through. Just get a couple Purolator inline fuel filters, put one in the glovebox as a spare. Also consider upgrading any rubber lines in your fuel delivery system to poly fuel lines, which are ethanol-proof unlike rubber lines that deteriorate with modern ethanol blended fuel.
 

ccmf22

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CONCLUSION !!!!!!!!!!!!!!!! so ive spent about two weeks messing with my damn edelbrock carb everything from buying new jets metering rods springs, needles n seats etc etc well the other day my accelerator pump "plunger" went so it gushed fuel out the top, and fuel ended up squirting out of the vents everytime my truck tried to start(caught my truck on fire on a cold morning because the damn truck wouldent start because the friggin carb kept flooding, luckily i noticed it right away and put it out) so i said F@#$ it and wooped out my old holley 600 carb rebuilt the damn thing and slapped it on and BAMN no dieseling, steady rps, doesnt sputter when i press the pedal and best of all it starts without pressing the gas, runs like its right from the factory:grd:
 

Irishman999

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CONCLUSION !!!!!!!!!!!!!!!! so ive spent about two weeks messing with my damn edelbrock carb everything from buying new jets metering rods springs, needles n seats etc etc well the other day my accelerator pump "plunger" went so it gushed fuel out the top, and fuel ended up squirting out of the vents everytime my truck tried to start(caught my truck on fire on a cold morning because the damn truck wouldent start because the friggin carb kept flooding, luckily i noticed it right away and put it out) so i said F@#$ it and wooped out my old holley 600 carb rebuilt the damn thing and slapped it on and BAMN no dieseling, steady rps, doesnt sputter when i press the pedal and best of all it starts without pressing the gas, runs like its right from the factory:grd:

HELL YEAH, so glad to hear that **** did not burn down dude.
 

Mike D

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Back in the late 70s - mid 80s the easiet ( and no cost ) solution was to turn off the ignition in drive, then place in park. The drag of the transmission instantly stoped the motor ( no dieseling ).
Solution #2 buy a new anti-dieseling solinoid used on a 1980 Suburban 350. It mounts on the side of the carb. It was unique in that it contained an adjustable vacuum and electric solinoid. You also need an electrical vacuum switch. Start engine adjust solinoid with small wrench. Back off linkage idle screw completely. Engine off throttle closes completely, no dieseling!
 

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