Hydraulic Lifting Keel

[Snowgoose-1]

I have a keel weighing 542kg with manual hydraulic lifting pump.

Each time I use the boat it requires about 15 pumps before any resistance is felt. Is this about right ? Wondering if something needs replacing or servicing .I keep the fluid topped up .
TIA

 

[wombat88]

I would suspect that the system needs bleeding to get any air out. I have no idea how this is done in your set up but the symptom you describe is similar to hydraulic jacks and even 'older' car braking systems that need bleeding.

However, if once you have pumped it up it starts going back down fairly quickly, ie can't hold pressure, then something is amiss for example a seal in the pump's cylinder.

 

[Tranona]

Is the pump connected directly to the keel or does it operate through a lifting strop? If the latter, maybe the 15 pumps is taking up the slack.

 

[Snowgoose-1]

I would suspect that the system needs bleeding to get any air out. I have no idea how this is done in your set up but the symptom you describe is similar to hydraulic jacks and even 'older' car braking systems that need bleeding.

However, if once you have pumped it up it starts going back down fairly quickly, ie can't hold pressure, then something is amiss for example a seal in the pump's cylinder.

Thanks . I will renew all seals this winter and bleed the system.

 

[Snowgoose-1]

Is the pump connected directly to the keel or does it operate through a lifting strop? If the latter, maybe the 15 pumps is taking up the slack.

Thanks . Could be a strong factor. The system has a piston which drives a 3:1 wire tackle .
After 75 odd meaty pumps a 25mm stainless bar is inserted through the keel box and keel to hold the keel in place. This eventually takes the pressure off the piston and tackle.
Sometime I will remove the keel furniture down below and see what's going on.