Carb. Adjustment

[ffdfireman18]

Does anyone have a link, or litature on how to adjust a John Deere DTLX18 carb on a John Deere A. I think it may be running rich. Thanks.

 

[David from Kansas]

Don't know for sure, but thought the operator's manual told how to do that. Is it running rich at idle or load? Two needle adjustments; one for idle, one for load. Try turning in the appropriate one a couple of clicks, or maybe one at a time to see what you get. On some DLTX carbs one click may make a difference but on others it may take 6-8 clicks. Just my experience with them.

 

[DScott]

Give a little more info about your tractor and the problem. What makes you think its running rich? Fouling plugs? Missing? Black smoke under load? Has the carb been rebuilt? What plugs are you running, and etc.

 

[ArnieinChesterfieldVa]

I'll betcha Mike Shelby will help ya out too.
http://www.popinjohn.com/

Arnie

 

[ffdfireman18]

When I start it usually I don"t even need to use the choke. If you choke it much at all it was put alot of fuel on the plugs, and start very hard. I put the new Champions in it that it called for, but I see in some of the other forums that people are using a Autolite 3116 plug. I think I might try that too. When I started it in the garage and went to bad it out you can hardly stand it, blackish smoke and it just smells real fuely. I bought it somewhat running, but just repainted it and put it back together, but I haven"t put it under a load yet. I plan on pulling a two bottom trip plow.

Thanks, Jeff

 

[DScott]

If I were working on that tractor the first thing I would do is get rid of those Champion plugs. You don't say what year A you are working on but since you are running a DLTX 18 carb I would guess that you need a set of Autolite 3077 plugs or if you have a later A then go with the Autolite 3116's since they use the smaller plugs.
As far as adjusting your carb goes, the service manual says to start with the idle screw 1.25 to 1.5 turns out and the load screw 1 to 1.25 turns out. Crank the tractor up, let it warm up good and then make further adjustments. When the tractor is running and you make an adjustment, pause for a moment to let the change have time to show it's effect.

 

[wilamayb]

If after adjusting your load and idle needles your tractor still does not run properly you should make sure you dont have any air restriction in your intake system pre carburetor. To do this remove the pipe from the front of the carb and see if it cures the problem.

If the problem still is not cured check the float level of your carb. It may be that your float is doing about as much sinking as it is floating causing the fuel level to be too high in the carb causing a flooding situation.

 

[ffdfireman18]

Thanks for the help. It is a 46 A, which is suppose to have the DTLX53 carb. on it, but this is the one they put on it off an early unstyled A. I got some extra parts including a broken carb, but I haven't checked to see if it is the DTLX53 yet. So I think I should use the Autolite 3116 plugs.

 

[BushogPapa]

I think most would agree that any 2-cylinder JD that shat starts COLD without needing choke is set too rich..
I can set my 630 Gas so it starts on the 1st turn every time, but it idles rich at that setting, once it warms up..set correctly, it also needs choke to start (Cold)..
Either you have the idle setting set too rich or the float level is too high..

Ron..