Ariens GT18 speed varying

[jnachtrieb]

My Ariens GT18 does not keep a constant speed, even on flat ground. Following the service manual procedure, I have tried to adjust the linkages, to no benefit. Any idea where to look or what might be wrong?

 

[ericm979]

Is the engine speed varying or is the engine speed constant and the tractor ground speed varies?
How does the speed vary? Increase, decrease, or random up and down?

 

[jnachtrieb]

Engine speed is constant. The speed varies up and down but depends on load--for example a small hill or when the front wheels are turned which causes drag. When the tractor "takes off" at a higher speed it feels like when a car's automatic trans locks in. The drive train also sounds different.

 

[jnachtrieb]

Engine speed is constant. The speed varies up and down but depends on load--for example a small hill or when the front wheels are turned which causes drag. When the tractor "takes off" at a higher speed it feels like when a car's automatic trans locks in. The drive train also sounds different. It reminds me of a slipping clutch in a stick shift.

 

[jnachtrieb]

Engine speed is constant, ground speed varies. Speed decreases under a load (small hill or sharp corner). Feels like a slipping clutch. Ground speed increases on level. Feels like when an automatic trans locks in.