Hydraulic steering system reservoir caps

[theglo]

Hello all,

I have an inside helm and a cockpit steering station on my Dufour 12000 CT. Both have integral hydraulic reservoirs. The caps on both have been drilled thru to add tubes to aid in bleeding the steering.

I'm looking to order NEW caps that don't have holes drilled in them but am having the hardest time discovering what size caps they are. The hydraulic reservoirs are original 1983, metric, likely Vetus.

Can you caliper some part of these to determine the size? The caps have male threads and screw into the reservoir tops.

Thanks,

Justin

[RaymondR]

Tap a thread in the holes and put a machine screw or hex plug in them.

[Pete7]

Justin, how are you going to allow for expansion of the hydraulic fluid with temperature changes in the system if you seal the vent?

On a previous boat during a sunny day the fluid would expand out past the vent hole in the cap if I topped it right up early in the morning when cool. A black helm pump unit probably didn't help.

Pete

[Bill O]

Is your system pressurized or a non-pressurized hydraulic system? As previously mentioned if non-pressurized the expansion tank is to allow for fluid heating. Technically the proper tank size should allow for the full range of fluid expansion w/o overflowing.

Our vintage Wagner hydraulic system is non-pressurized and added an expansion tank to help monitor levels/potential leaks. The expansion tank was also needed for the AP pump. Added a self contained bleeding system so we could do it on the fly (if needed) and contain all the fluid. This really avoided the mess while bleeding and drawing air into the system if the reservoir got too low during bleeding.


Bill O.