We will start to pump but driver side hits the top of the stroke and stops. Any ideas where to stat trouble shooting would be greatly appreciated. 

Proximity switches?

Concords don’t have proximity switches

If u take the pump out of pto then try and put it in 7th great and engage pto does it kill the engine or pressure out?? If so could b broken spring or orfice /set screw in logic valve 

Did you resolve the issue? Mines doing the same thing. 

Proximity switch?

Chech valves on diff cylinders or shift block 

Troubleshooting Concord Pump Stroke Issues

When your Concord pump's driver side hits the top of stroke and stops, this is typically related to the hydraulic shifting circuit. Unlike some other brands, Concords don't use proximity switches for stroke detection.

Primary Areas to Check

1. Logic Valve Issues

   • This is a common cause for Concord pumps with your symptoms
   • Check for:
     • Broken spring in the logic valve
     • Clogged or damaged orifice/set screw
     • Worn seals allowing hydraulic bypass

2. Test Procedure
   As suggested by Pnw pumper on the forum:

   • Take the pump out of PTO
   • Try putting it in 7th gear
   • Re-engage PTO
   • If this kills the engine or pressures out, it confirms logic valve issues

3. Shift Spool

   • The shift spool may be sticking due to:
     • Contaminated hydraulic oil
     • Worn components
     • Improper adjustment

4. Hydraulic Pressure

   • Check for proper hydraulic pressure to ensure there's enough force to complete the stroke cycle
   • Look for relief valves that may be opening prematurely

Additional Considerations

• Oil Temperature: Excessive oil temperature can cause components to expand and bind
• Mechanical Issues: Check for any physical obstructions in the cylinder path
• Control Block: Inspect for internal leakage or worn components

This is a recurring issue with Concord pumps that several operators have experienced. The logic valve and shift mechanism are the most likely culprits based on the symptoms you've described.

Would you like me to provide more detailed information on how to inspect or repair any of these specific components?