Carb setting

Tiny
REICHARTAR
  • MEMBER
  • 1983 FORD F-150
  • 6 CYL
  • 4WD
  • MANUAL
I have a 1983 f-150 4.9 300-6 1 barrel carter carb with 1 adjustment screw, 4x4 no air. I moved from sea level to above 3000 ft. At sea level the carb. Adjustment was approx. 2.5-3.0 turns from screw all the way in. Approx how many turns at higher alt. I checked timing and choke. It wont crank with out pumping the gas pedal. Also poor mpg once running. Thank-you, TOM
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Monday, June 13th, 2011 AT 9:20 PM

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Tiny
RASMATAZ
  • MEMBER
Check choke adjustment/pull off-close the A/F mix screw and back it out 2 1/2 turns out -readjust the idle speed to specs-also check fuel pressure/volume-sounds more like a carb internal problem-float system
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Monday, June 13th, 2011 AT 9:38 PM
Tiny
WRENCHTECH
  • EXPERT
That adjustment is for idle air mixture only so it has nothing to do with your issues as Ras pointed out.
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Monday, June 13th, 2011 AT 9:43 PM
Tiny
CJ MEDEVAC
  • EXPERT
Are you using "Household" tune-up gauges and equipment to Tweak your carb?

Do you have that kind of necessary stuff? (I have a suggestion, if you do not)

Pumping the pedal is not an uncommon thing on a carburetor equipped vehicle.I seldom use my Manual choke, on my CJ5, 3 pumps on the pedal and putter around till I get warmed up good. Or I'll go 1/2 choke (for better cold performance) until I get to operating temp.

I prefer a properly installed manual choke over automatic, I know when it's off or on, and can decide when it's time to cut it off (not prolonged, as with an auto choke) It's EZ to test for correct operation going down the road.

I do not "Depend On Correct Performance" until I'm at operating temp. Like jumping into traffic! Otherwise, Mr. Jeep might "hiccup", when I need power the most!

Do you know how to properly adjust an automatic choke and it's steps. Just fiddling with it, may not insure it works as it should!

Has anyone disassembled your carb, and changed the innards?

How long has this carb been operating without being rebuilt? (Time/ miles)

Sounds like you need to do a FULL SCALE TUNE-UP!

You might also check all of your VACUUM LINES/ AND VACUUM OPERATED GOODIES, FOR LEAKS. Including the torque on your intake bolts and hold-down nuts, carb to intake. And the screws that hold the carb together.

Are you capable of doing all of this yourself, or do you need a On-line helper(s)?

I have a 258 in my CJ5, it's not much different than yours.I have some homemade pics that may, help, if they are needed, as we (may) continue to get you to assist you.

If you'll do all of the labor, and keep up, we'll "Straw-boss" you, thru the process!

Your turn. We can keep this going forever, if you are game!

The Medic

. Someone please discredit my attempt to help!
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Tuesday, June 14th, 2011 AT 4:10 AM
Tiny
REICHARTAR
  • MEMBER
Whats funny is I bought the truck 4 yrs ago in sheridan wy. I always had trouble cranking it no matter what I did. Last aug. I drove it to fla. To see my dad. I didnt think it would make it, but it did. Once in fla. It cranked fine, 1 pump of pedal it would crank and idle by itself. Two wks ago I came back to wy. S.O.S. Carb was rebuilt 2 yrs. Ago. Before I left fla. I installed new plugs, wires, cap and rotor. I like the idea of manuel choke have always had trouble with auto. Yes I have replaced guts to auto choke, I have a manuel choke cable assy. But have never installed one. That may solve my problem. Do you have any helpful hints on install. I have been a backyard mech. For over 25 yrs and have some knowledge, but carbs have never been my cup of tea. THANKS FOR YOUR HELP. TOM
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Tuesday, June 14th, 2011 AT 7:16 PM
Tiny
CJ MEDEVAC
  • EXPERT
Sent you a message (Home, click on your name, look left), hurry up and respond about the tuning.

This is an inexpensive set. Works well! Compact and almost all you need in one spot--minus wrenches and screwdrivers!

Less than $40, at "Harbor Freight"

Got all of the vacuum lines/ vacuum stuff checked?

Let us know when you are ready to start!

The Medic
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Tuesday, June 14th, 2011 AT 9:32 PM

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