751 Not operating correctly – Nice list of hints
Q: When we set the valve to forward (pressurize 3) yes the cylinder goes to the marking stamp, when it touches the part a locking sound comes but the air leak comes from point 1 and point 2 even it stops moving. Like there is no isolation for air in the cylinder. And when we set the valve to backward, because of the air leak continious the cylinder moves so slowly and sometimes not moves back. This happenning for both side’s cylinders.
What is wrong with this installation?
A: The information and #1 #2 #3 below is based on your photo we received
#2 
- Takeoff flow controls now at both #2 & #3 positions.
- Replace with standard elbow fitting. NO FLOW CONTROL (some countries call them air peed controls or air metering devices).
- Marker has internal air flow speed controls which is fixed and extra ones make it hard for marker to go forward and back properly.
#3
- The “kinked” air line in the photo (#3) is keeping the marker from moving correctly in both forward and return directions.
- Replace air line with new air line.
- Do not suggest using repair splice like in photo, these can restrict air flow and power.
#1
- The air rushing out is normal and supposed to do this however for only .5 seconds.
- This is how the slide-a-mark air tool must work.
- You must have air valve timer set incorrectly.
- Total cycle time to Advance-Mark-Return should be 1 second maximum
- Set air on advance (#3) port to very short time less than 1 second.
- Turn off air #3 and energize air valve to port #2 instantly no delay.
Here is link to Manual which shows air circuit diagram I simplified above. http://columbiamt.com/CMT-Impact-Marking/Catalog/751_OG_parts_and_spool.pdf
Very important. This link clearly shows and explains how the marker works. http://columbiamt.com/CMT-Impact-Marking/Catalog/Slide-A-Mark-8_10-Ton_WF.pdf
As a final notes for #1 area. I noticed you have the holder rotated so the screw which holds it on the rod end has been rotated.
- This is fine however please read the Manual (link above) that says if you over tighten the clamp or sometimes called a collar on the rod for orientation it will cause it to stick when the spring collapses to fire the hammer.
- You have not mentioned this but it might happen if someone over tightened it.
- The small bracket looks like a switch is in the way to loosen the holder screw.
- Do adjust the air pressure to only that which is needed for a good mark.
- Do not run marker at higher air pressure than needed. 2 to 6 bar is the operating range with 4 being the normal settings for most applications (in USA it is called 30 psi to 90 psi or 60 psi is normal).
