Hard throttle on a 400

[36b A]

Have a 400 gas with a M&W governor . when moving the throttle lever with the motor not running it moves like normal . There is no binding . but with it running you really got to pull on it to get to wot . I had a super m with a rocket on it and it didn't do that . Any ideas to look for ?

 

[Mrfred54]

Remove the governor cover and run the tractor. Have s helper pull on the throttle lever and watch the weights of the governor. Maybe have a bind while they are spinning. You'll lose a small amount of oil but no big deal. Notice if there is a big difference in the spring length from running engine compared to when not running