C160 auto w/Sunstrand 90-1140 too fast in forward

[davidtmercer 58]

I have a 1973 C-160 auto with Sundstrand 90-1140 installed.  It has the hydraulic lift.  The forward speed is too fast and can't be properly regulated with the centrally located forward reverse lever.  Reverse speed is fine.  Any assistance in resolving this would be greatly appreciated.

[ebinmaine 68,554]

Can you elaborate on "too fast"?

 

Are you not able to slowly move the motion control lever forward to go at a crawl speed?

Does the tractor jump from stop to a certain speed?

 

A hydro is faster at top speed than a manual transmission tractor but the variability from 0 to peak should be infinite.  

 

 

Point of info... C160 started 1974.  

 

 

[davidtmercer 58]

Wow, thanks for the prompt response!  You have clarified the issue by concisely describing that I am not able to slowly move the motion control lever forward and operate at a crawl speed.  It will stay in neutral but when I move the control level forward it does jump automatically from a slow forward to maximum forward speed.  You are correct, the tractor is a 1973 16 auto, not a C-160 AUTO.  The Sunstrand 90-1140 is a retrofit.

[squonk 41,474]

First guess is the acceleration spring. 

 

2nd guess. I had a sudden situation shortly after I bought my C-160. It was very erratic in forward, almost seemed like it was binding up. checked the spring and it was ok. I ended up having to replace the hydraulic motor half of the trans.

[pfrederi 17,912]

Is the plastic slider broken and or cracked  (yellow circle)

Try a neutral adjustment

 

 

[davidtmercer 58]

It was the speed control lever tension adjustment.  I took it apart, cleaned it in solvent, replaced it and adjusted it per instructions. The spring is almost fully compressed but it is currently keeping the control lever from moving.

I am planning on replacing the acceleration spring and the plastic slider as preventative measures

Thanks for your recommendations.

 

Dave