So I spent all day working on a friends 400 that hasn't run in over a year.I took the carb apart, cleaned it up, and carefully reassembled it with a new bowl gasket. The problem is it won't run for $h!t now but it wouldn't run at all before. Plugs wires points cap and rotor all are fairly new. This tractor ran well before it was parked. My question is what is the proper adjustment for the high speed and idle adjusting screws? At first it would only run at full choke now it will run without choke but it's very rough. I do quite well with gas Oliver's and 2 cylinder deeres but I really don't seem to get along with the farmall gas burners. I got my butt kicked by a h I couldn't fix awhile back too.
 
open the main jet at bottom of carb 4-5 turns open and go from there. usuall putting around is about 2 1/2 turns out. the idle mixture i find 3/4 - 1 turn out is about right. the idle is to be as

slow as possible in the 400 rpm range to prevent run on when shut down.
did you soak it in carb cleaner and blow all passages out with air? did you remove pickup tube also as it has lots of tiny holes in it that plug up.
 
I used a whole can of carb cleaner on it and cleaned out every hole I could fine. I know the adjustments are off from what you recommended. I will try it tomorrow if I get a chance
 
kinda dont tell me much, appears like you just removed the float bowl from the top section and cleaned it with spray. you did not say if you unscrewed the pickup tube and cleaned that along with the main jet. and blew the passages out with air. you can see each passage this way. i poke each little hole with a fine tag wire also. i spray wd40 into the passages then blow out and watch for the mist to come threw each one. thats after soaking them in the actual real carb cleaner for an hr. or two.then wash with warm water and blow out. to me that spray stuff is a waste of cleaner and time.
have to ask questions to find the cure, because not there to see it visually.
 
I used the spray. That's all we have access to here and I was unaware of anything else. I sprayed every thing good and let it soak awhile then I used a fine wire on every hole. I took every part out of the carb and cleaned it I didn't just split it in half. Like I said I can make Oliver's allischalmers and 2 cylinder deeres run and I've even had some success with small block chevys I've just never had success with ih carbs. I've messed with a 656 a h and now this 400 without real good results. I'm just not sure what I'm missing here. I can always make them better than they were but never satisfactory.
 
u might have to just open the main fuel jet at the bottom of carb to at least for turns out from seated position. i always count the turns on any carb.
 
Thank you for the knowledge i will give it a try. Hopefully we can get the old girl running she has always been a good tractor.
 
I always check spark. You need a good blue/white spark that will jump a 1/4 inch gap or more at the center wire of the cap and at all the plugs.
As for the carb if you do not poke out all the passageways with a piece of wire or as I do it a torch tip cleaner tool you can/will leave behind some dirt/rust that will cause problems.
You also need a good steady flow of gas out of the carb drain plug that will fill a pint jar in less then 3 minutes
 
i would say if your taking 3 minutes to fill a pint u got restrictions happening. that pint should be full in at least 30 seconds depending on the hydrosatic pressure from the tank level.
and that spark better be jumping 1/2 to 3/4 of an inch and snapping.
 
So have you ever timed gas flow out of the carb drain?? I have and the flow should take as I said LESS then 3 minutes and ya 3 minutes is a bit slow but still fast enough
 
how did u think i came up with the answer??? do you know how long three minutes is? the w9 mccormick will burn it faster than that.
 
I want to thank everyone for the replies and your time and knowledge. I probably won't be able to work on the old girl again until next weekend. I will let you guys know how I make out
 
no kicks yet, but anyhow the proper way to check the fuel flow from tank is at the carb inlet, as i said . i dont see how waiting 3 minutes for a pint to fill after running through the needle and seat accomplishes anything other than the needle is not stuck closed. you still can have a partly plugged line or restriction in sediment bowl and the tractor will run or idle till you need full power then it will be cutting out due to gas starvation. far more important to check and know there is good flow to the carb and know the needle is not stuck than worrying about timing a carb draining.
 
If you take the carb apart again get some wire welding wire. The diameters go down low enough to use them like pipe cleaners . Get a wire thru every hole and blow good with compressed air.
 

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