Sinar P2 8x10 Back hydraulics question...

[Dustyman]

The 8x10 P2 Meter Back has a lovely hydraulic tampering system that results in a very soft closing of the back when you remove the holder.
However, with my back, it seems that, every so often, the hydraulics don't "kick in" properly and the back snaps back hard quickly. Then, after that, it somehow heals itself and returns to the nice soft closing action. I can't intentional repeat the aberration, but it seems like (and I'm not 100% sure about this) it happens after the camera sits unused for a bit. The first closing snaps shut hard, subsequent closings are soft and sweet.

Has anyone had this same experience? Any ideas?

[asf]

The piston is gummed up, you can clean and maybe regrease

[Dustyman]

Thank you, I've come to the same conclusion.

What would you suggest for cleaning? I was thinking of Ransons lighter fluid.
Not sure if there are rubber gaskets inside the cylinder, and I don't want to use anything that could contribute to rotting them out.

The piston is gummed up, you can clean and maybe regrease

[asf]

Good question, I couldn't say for sure as I had one done for me by a tech a while back, works nicely now

maybe just try to keep it exercised for a while and see if that is enough, or give it an easy wipe and a drop of light grease