Tool Release Piston Failure?

[JoBwan]

Good Morning Everyone.
I have a 1998 VF-10 (serial# 16018) that keeps breaking the snap ring on top of the piston shaft. I just finished last week replacing the complete tool release piston assy., due to it had broken the piston shaft also. A brand new assy. and it has already broken the snap ring again. I have checked the pre-charge pressure, and it was set @ 18 PSI. I adjusted this down to 6 PSI, and was wondering if that could cause a snap ring failure. This machine has TSC, but is used rarely (twice a year). Can anyone give me an opinion or a fix?
Any help is greatly appreciated!

[Loose Nut]

Has the TSC been used since the new piston was installed?
Pre-charge pressure too high can cause the shaft to spin, vibrate, tear up...

Do you have a service manual? Did you adjust the drawbar pushout correctly?

What is the main air regulator set to? If set too high it can cause the TRP o-ring to blow out.

Are tools sticking in the spindle?

Loose nut

[JoBwan]

Has the TSC been used since the new piston was installed?
Pre-charge pressure too high can cause the shaft to spin, vibrate, tear up...

Do you have a service manual? Did you adjust the drawbar pushout correctly?

What is the main air regulator set to? If set too high it can cause the TRP o-ring to blow out.

Are tools sticking in the spindle?

Loose nut

Nutty,
I tore this back apart to replace the snap ring. I had to add .020" shim to the piston screw. According to the manual, I now have it adjusted properly. Pre-charge is set to 6 PSI. Main air is set at 85 PSI. No, the tools don't really stick in the taper. I have re-assembled and hope the .020" does the trick. Thanks for asking questions. It helped me to see what may have previously been overlooked. Two heads may be better than one?

[rlabonte18]

How much drawbar pressure do you have?

[JoBwan]

How much drawbar pressure do you have?

riabonte,
I thought the same thing. Checked it with a new "Clamprite" gauge. It is showing 1150 lbs. of clamping pressure. The manual calls for 900 - 1300 lbs. to be in the safe range.