M or 450 Carb???

I have been on here for a few days trying to figure out a starting problem on my M. I am trying to get my carb to initial settings and start from there. I have been reading about the high speed screw and idle mixture screw locations and thought everyone was crazy because none of the screws are in the right place on my carb. So, it turns out that the carb is apparently a 450 carb and I need some help on which screw is which..it"s always something!!!..thanks!

(quoted from post at 19:35:28 06/24/11) I have been on here for a few days trying to figure out a starting problem on my M. I am trying to get my carb to initial settings and start from there. I have been reading about the high speed screw and idle mixture screw locations and thought everyone was crazy because none of the screws are in the right place on my carb. So, it turns out that the carb is apparently a 450 carb and I need some help on which screw is which..it"s always something!!!..thanks!

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The high speed screw is located at the bottom of the carb, pointing forward. The M and the 450 are exactly the same. Gently turn that screw in until it seats. Do NOT force it. Once it is all the way in and seated, turn it exactly 3 turns out. If the engine misses or stumbles during wide open throttle, full load conditions, turn that screw OUT an additional 1/2 turn at a time until the stumbling goes away.

The idle mixture screw on the 450 carb is located in the flange that bolts to the manifold. It is different from the M. If you have the carburetor off, put your finger down into the throat of the carburetor. Turn that screw in until it stops. You should then be able to feel the point of that screw with your finger. Turn that screw back out just enough that you can no longer feel the point with your finger.

If the carburetor is ON the tractor, turn the screw in gently until it stops, then turn it out 1 full turn. Minor adjusting will be necessary after the engine is warmed up.

If these adjustments do not effect how the engine runs in any way, shape, or form, it is time to do a complete disassembly and thorough cleaning of the carburetor.

Thanks again for the help. There are 2 screws with springs on the upper part of the carb. The top one faces straight outboard, and the one right below it is angled out and forward. On the front of the bowl, there is a small screw with a locking nut. DOes this sound like a 450 carb? Or do I have something else? I can send a pic, if it helps, but the only one I have is on my phone. Thanks again for all of your help.

Insert your email address to your phone contact listing on your cel. Then simply send the photo to youe PC email.

Sorry, I don't have that capability. I can usually send one to my email via the Verizon website, but that isn't working today either. If you PM me your cell number, I could forward the pic from my phone to you.