Hydraulic Pump question

[rebuckley]

The Defender sale is here!!
I was seriously thinking about a simrad auto-pilot system to snyc in with my simrad gear. My main issue is the size of the pump for the system?
I am right on the cusp of boat size (36') for thier two pumps RPU80 and RPU160. The big difference is in the RAM capacity (4.9-15.2 cubic inches vs. 8-24 cubic inches) and max pressure (50 bars vs. 60 bars).
The boat is still covered, and I have gone through all of my documentation - I cannot for the life of me find any specs on the hydraulic system? Any advice?

[carolmarie]

I could be remembering wrong, but seems to me there is (was) a table in the Defender catalog listing the various Sea Star hydraulic cylinder models vs the recommended Simrad pump size.

[jleonard]

Check out the Sitex SP-70 that's what I have and it's less expensive I believe.
But regardless...when I bought the Sitex I opted for the larger pump. I measured the OD of my steering cylinder at the time and made my choice.
I don't remember the volume though, other than knowing I needed the larger one. The price was the same so I made my choice.

If the pump is too small the result will be a little slower response. Certainly not the end of the world at 7 knots! You may not even notice.

[Tree]

Just a heads up - any pump will work. for Example, Raymarine, Simrad and Furuno all use the same pump made by Hypro here in the UK.

We bought direct from Hypro and the cost of the pump was less than half of the electronics dealers RRP.

http://www.hypro.co.uk/hydraulic-autopi ... ower-unit/

[rebuckley]

Thank you all! - I figured the smaller pump would be alright - but Defender was awesome, and let me put together the similar package (and save a little) which means the pump is an individual item, incase I need to size up!

[RobS]

I just installed a Simrad AP24 (N2K) autopilot system on my boat including the RPU80. Here's the pump sizing chart and some pics of my install. Hope this helps. If you want any pics of the install of the other components just say so. Good luck.

Simrad Pump Specs.jpg

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2015-03-07 12.20.21.jpg

2015-03-09 16.55.01.jpg

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2015-03-09 15.40.09.jpg

[Panhdjoe]

Hello I also have a 1983 36 hull #364 ours is equiped with Hynautic steering. I have the orignal manual and instalation guide for the system. The manual is on the boat now I will be down to the boat on monday. If you would like I will ceeck it out for any helpful info. I doubt they used different systems in the same year but one never knows.. Joe

[Tree]

One thing to make sure is that you have check valves installed. Most steering pumps like seastar have the check valves built into the wheel pump ready. The autopilot pump should have check valves installed also, otherwise you will be "powering the wheel" instead of powering the hydraulic system.

[jleonard]

I believe these old Albins don't need anything else but the pump. I don't have anything extra in mine and it works fine. I get a little wheel action back and forth but that lets me know the system is on and working

[Panhdjoe]

Hello, The manual only has a list of the 4 cylinders that can be used, I have found the recipt from the boat yard for the replacement cylinder they installed when the water tanks were out. I had it replaced as a percaution. It was a 13.3 cid K22 10in brass cyl. Don't know if thats any help, good luck. Joe

[rebuckley]

Thanks Joe, that matches with the other size I found elsewhere , the RPU80 should be fine.

[rebuckley]

The RPU80 is in and worked perfectly for Block on the 4th. Even the folowing sea on the ride home had no issues.

[jleonard]

Awesome

[varmont]

I installed a Raymarine APU400 system this spring using the Type 2 pump.

Technically the Type 1 pump should have worked because the ram volume is within the upper bounds of the type 1.

I chose the type 2 for a couple key reasons
* type 2 has higher capacity so it takes shorter amount of time for rudder stop to stop
* type 2 will run shorter periods of time than type 1

After cruising this summer I was VERY thankful to go with the type 2 pump because of the quicker response.

In mid following seas the type 2 was fast enough to push the rudder from center to 20+ degrees faster than I could turn the wheel. The system was able to follow the course and only deviate a couple degrees either side as the waves overtook us. With the slower type 1 pump it would not have been able to keep up.