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Carb problems

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Sprint17hb View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sprint17hb Quote  Post ReplyReply Direct Link To This Post Topic: Carb problems
    Posted: Jun/19/2021 at 2:52pm
Installed new stock carb on 84 wagoneer. Replaced due to leaking and was easier to replace then rebuild.  Engine ran good b4 except leaks now it won't idle unless I stay on gas or hold the choke plate closed.  I believe I may need to increase fast idle bit just want to be sure b4 I do.  Any ideas would be very appreciated 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Heavy 488 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/19/2021 at 4:12pm
Butterfly closed is not  enough fuel. Have you adjusted the mixture screws?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sprint17hb Quote  Post ReplyReply Direct Link To This Post Posted: Jun/19/2021 at 6:16pm
I have adjusted nothing yet. It supposedly is all factory set with possibility of having to do curb idle. I never trust that but just trying to make sure b4 I do anything
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Heavy 488 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/19/2021 at 6:54pm
Idle mixture screws don't hurt to check. Turn in gently til you feel it stop, then back out 1-1/2 turns for a base line.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote IB Sorgn Quote  Post ReplyReply Direct Link To This Post Posted: Jun/19/2021 at 7:07pm
Probably drew contaminants into the fuel when changing or there were contaminants in the new part(s).  Pull idle valves and blow out circuit.
Had same happen to me few years ago. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ram Air Rick Quote  Post ReplyReply Direct Link To This Post Posted: Jun/20/2021 at 6:29am


Sprint ....  Heavy is giving you great advise. 

Make sure you don't have any vacuum ports on the carb either not connected to a hose, or at the very least capped off.

From the sound of it, it sounds like the idle circuit is way lean. You closing the choke is choking the air off and making the air fuel ratio closer to what it needs to be to idle. 

I'll add this to Heavy's advise:

 - Refer to the idle mixture screws as passenger side and driver side (left and right gets tricky depending how you're viewing it)

- It would be helpful to learn where they are right now for reference so, to find out where they are now, turn each idle mixture screw in a 1/2 turn at a time, since the screw slot is a good reference for counting it that way. 1/2, 1 ,1-1/2  etc. until you feel it seat (soft stop) (do NOT tighten it) as that could mess up the screw or the seat. Note the amount you need to turn each mixture screw in. 

- Now turn each screw out 1-1/2 turns . This is a typical good starting point.

- If you have a vacuum gauge connect it to manifold vacuum.

- Start and warm up the engine so it drops down to idle off the fast idle cam. Observe the vacuum gauge. Is it steady? How many inches of vacuum? Turn each idle mixture screw out 1/4 turn. If the idle speed and vacuum picks up turn them out another 1/4 turn. You'd be at 2 turns out there. Continue this until it wants to idle smooth. If you get past 3 1/2 turns out you're approaching the limit of the idle mixture adjustment.

 - This may or may not be the problem. It's just a methodical way of determining what could be the issue, and if not, allows you to return the mixture screws to the base adjustment from out of the box.

 Good luck

Rich Corsello
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Post Options Post Options   Thanks (0) Thanks(0)   Quote mixed up Quote  Post ReplyReply Direct Link To This Post Posted: Jun/20/2021 at 8:05am
ram air is right on the money  most carb require adjustment out of the box    
69 amx 290 auto
65 220 290 4spd
80 ford fairmont
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sprint17hb Quote  Post ReplyReply Direct Link To This Post Posted: Jun/22/2021 at 5:15pm
All that would be great but I can't even get it to idle cold so in order to get it to warm up I need to hold the butterfly closed so it will idle. That is why I thought the fast idle is not correct
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Heavy 488 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/22/2021 at 6:18pm
So you didn't try the idle mixture screws?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sprint17hb Quote  Post ReplyReply Direct Link To This Post Posted: Jun/22/2021 at 6:23pm
I have. She idles a little while until I touch the gas so when I have time later after work I'm gonna play with it some more and I'll keep you updated.my other thought may be bad gas this thing sat for 16 yes b4 my dad started playing with it and he died over a yr ago an0d I just recently started going at it
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