E36RH Backstay cylinder and Vang pressure

[EngineerSailing]

greetings, I have what i think is the original back-stay cylinder and Vang for my Ericson 36 rh
It has been over 20years since the prior owner had them rebuilt
Looking at Navtec Hydraulics website Navtec Hydraulics
I find the Vang should be charged by the rebuild to between >600psi and <1000psi
All i see on the backstay cylinder is the relief valve pressure, but no pre-charge settings for the rebuild shop

these are the only labels i saw
Note: there is no topping lift on the E36RH, the vang supports the full load of the mainsail and boom when dropped or reefed

When others have had Navtec cylinders rebuild do you remember what pressure you had the rebuild shop charge the cylinders to?
Has anyone found the Vang has a sweet spot pressure (if that still exist on a 43year old Vang)high side or low side?

Thanks, Carlton

 

[ConchyDug]

I'll preface I have zero experience on Navtec Vangs and precharging them.

I do have a ton of experience in hydraulics and servicing aircraft landing gear struts though. So my advice is to install it and start precharging it SLOWLY with someone lightly bumping the boom up. When the boom is lifted to where you want it stop servicing. I'm guessing you're using nitrogen? If you are dealing with 100psi or more I'm guessing you have a regulator and bottle? Looking at the procedures manual Table B is your friend. 1000psi is the absolute max. From the table I bet you'll be in the 150-300psi range.