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Topic Review (Newest First)
01-03-2013 01:39 AM
jeepchix Great! lol
01-02-2013 07:38 AM
aelwero the major carb adjustments are Idle, fast idle, choke, and idle air mix.

None of them should prevent the engine from starting. When you hit the gas pedal, none of the adjustments do anything anymore, they only affect idle. The "adjustments" with the throttle open are effectively your metering jets. To get more or less fuel ratio at open throttle, you use larger or smaller jets to change the air/fuel ratio (usually to "adjust" for altitude). If it wasn't "jetted" for your altitude, the mix may be off far enough to prevent it from starting.

When you rebuilt it, did you replace the needle valve? Small brass fitting deal that goes in the bottom of the bowl. It cuts off incoming fuel when the bowl gets filled to the proper level. It's (arguably) the most common thing to screw up in a carb. If the float is set too low, installed wrong, or if you reused the needle valve (they get old and stick), it may be keeping the fuel from filling the bowl internally, so you may have fuel flowing at the incoming line and not getting into the bowl. If you take it off, flip it, and a fair amount of fuel comes out, you're probably OK.

Occasionally, you have the other problem, where fuel doesn't stop getting pumped in, the bowl fills completely, and the fuel can't atomize, but that is almost always a very obvious problem (liquid gas flowing down the carb throat and/or on the outside of the carb).

Does your choke open and close? should be closed with it being winter. That shouldn't keep it from running if you're using ether, but if it isn't closing, that certainly won't help...

there's a lot of little things that could also have been overlooked during the rebuild as well, and there are a bajillion differnt types of carbs, all with their own metering, valve, venturi, etc. designs... Best bet is make friends with a carb guy that lives close to you
01-01-2013 02:12 PM
jeepchix PPS: Thanks for your guys help! Anything will be great! I need my baby running again!
01-01-2013 02:11 PM
jeepchix Did I get it jetted? -Not sure I did a rebuild on it, with all the correct measurements.

What did you start with? Was it a running motor or parts and pieces you assembled? Do you have a manual that tells you how to set it up for basic timing, carburetor adjustment?
-I started it like normal, gas was flowing, it wasn't catching so I used ether and it catches and started until it burned up. Manual choke? No. But I dont know what ya mean when you say, Cab adjustment.

Is it a new carb or from a donor?
-Donor, but the correct 1.08 for the swap.
-I am not sure why It will start with the ether but not the fuel. My guess at first was does the fuel(a lot of fuel) need to fill the bowl?

PS: additional info. I am also trying to start it now in colorado...=/ so on top of that its cold.

It be nice if anyone has the settings the carb needs to run here.
12-31-2012 11:14 PM
aelwero take off the carb and turn it upside down over a bucket. Should dump out about a quarter cup of fuel. If not, you got pump/filter/needle valve issues. That seem slike the most likely if it doesn't fire at all.

There's a whole ton of things that it could be though. Major vac leaks, clogged ports, float level...

Is it a new carb or from a donor?
12-30-2012 10:59 PM
div4gold What did you start with? Was it a running motor or parts and pieces you assembled? Do you have a manual that tells you how to set it up for basic timing, carburetor adjustment?
12-30-2012 09:11 PM
sledn8r Did it get jetted for altitude?
12-30-2012 07:47 PM
Motorcraft on the 258 problems and questions.

Hello! I recently done the motorcraft swap.
Everything is hooked up and ready to fire and then I go to fire it up it wont start. I sprayed ether and it will run however it wont catch and stay running so it seems like everything function with wiring and what not. Now I don't know what how much fuel is required to fill the bowl.

Recap: everything hooked up. Fires up wont stay running with ether, need help!
Also I don't know carbs so if you can give specifics on how to make the adjustments and idle and things like that run properly and be correct that be a huge help!

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