Farmall super a throttle

PatrickW3578

New User
Hello. I just bought my first old tractor. 1950 super a. Got it at a great price and nothing is much wrong with it. Only problem I?m having is my throttle. When I have the throttle held wide open at the control I?m only running about half of what it should be. I can move the arm on the side and it will rev up correctly with no problem. also, tractor has to be about half throttle to start and cuts off. Idle is at the half way mark of the control. I?m guessing jts a linkage off somewhere?
 
It sounds like a lot of things are out of adjustment. The idle screw should be set on the carb so that it will not die when the throttle is pulled all the way back. The linkage to the carb from the governor sounds like it is adjusted incorrectly as well. Your best bet would be to get a service manual and go through the proper procedure for setting the linkage and carb adjustments.
 
On the left side of the engine the throttle linkage has an adjustable clevis on the end and connects to an arm that moves the governor parts. If I remember correctly with the pin removed that makes the connection if the throttle arm is pushed completely forward and the governor arm full back toward the operator they are set up correctly when the pin can be reinserted. If that is the real problem its hard to understand why it be would off that much - it can't change on its own.
 
I've bought a few tractors where things were so misadjusted or misassembled that the tractor just wouldn't run or run correctly. Some people just don't know what they are doing and give up after a while. I just bought an M that had the points gapped as far as possible and everything in the Carb was loose, but you could tell that both the points and carb parts had been recently installed.

I bought an H that the previous owner had "rebuilt" the carb by removing all the internals and putting the two halves back together, and after he couldn't get it running again he listed it for sale.
 
When I bought my 300U the guy said his son in law had over hauled the engine and now it won't turn over. He had the crank shaft bearings in the wrong order. The middle one is smaller than the outside ones.
Once I changed them it turned over fine. I'm willing to bet the packaged was labeled. Some people shouldn't be allowed to remove the gas cap, let along work on the engine.
 
It could be the linkage adjustment wrong or it could be the thruster bearing in the governor is shot and needs replacing.
you will loose throttle response if the bearing is wore out. very common on A,B,C
 
Mine had the same symptoms and adjusting the throttle linkage at the clevis on the left front of the engine fixed it. Someone had fooled with it years ago and got it off I guess. Later I took the governor off to fix a front seal leak and found the gov thrust bearing had come apart (balls fell out from between the races) I replaced it, reassembled everything, and rechecked the adjustment at the throttle linkage and it had not changed. Be prepared to have to heat the clevis to get to turn on the linkage rod to prevent twisting it off. Mine was stuck.
 
Sounds like the 450 I bought a couple of years ago. I bought it not running, but free. I got it running, but it had poor oil pressure. When I dug into it, I found that someone had recently overhauled it but put standard rod and main bearings in it and the crank had been ground .010 under. I mic'd the crank and it was all good, so I bought a new set of proper bearings and installed them in it and all is good now.
Tractor runs like brand new after getting the carb cleaned up and adjusting the timing properly.
 

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