I am about to use my first air operated retract system ( 1/5 P-51 with Robarts ) and have a question or two.

1) - Is it a good idea to spray a bit of oil or WD40 in the system from time to time.

2) - Is it OK to grease with Vaseline or something the plastic blocks where the locking mech travels, they seem to stick a bit and make the operation somewhat jerky.

3) - What is the max. air pressure to use, trying them in the shop I pump up to about 120 psi - too much ?????