Mechanical to hydraulic steering conversion and addition of auto pilot

N

NH Tooner

Member
Aug 31, 2012
160
NH
Boat Info
1986 270da and 1979 260da
Engines
375hp 496 Magnum with Bravo 3 and 260hp 350 ci OMC
I am going to be doing this conversion. Cant find any real info anywhere. I've got it figured out. Anyone interested let me know and I'll post the conversion here.
 
I've been doing research on the same thing. I have mechanical steering with power assist from the steering pump on the motor. 2007 Mercruiser with Bravo 3. The following is what I found to be the best way to go. I'm using a garmn7612xsv.
Some people told me to use an octopus drive. but no one had feedback on an actual installation. I tried that and was sloppy at best. I went back and forth with Octopus and they finally said I might have a defective unit. I spent enough time with that and sent it back. I didn't want to deal with it. Now after winter research I've decided to convert to Hydraulic steering. Again people said to add a cylinder and helm and eliminate the power steering from the motor driven pump. Again no actual feedback from people who have done it. Now this is what I'm going to do. Convert to hydraulic steering using a Seastar HH5271 helm. Seastar cylinder HC5328-3. this will allow me to continue to use the power assist motor driven pump. You don't even need to tap into that old system. It will be like having 2 separate hydraulic systems. I got all this information from Seastar tech help. next I will use a Garmin 1.2lt pump, Garmin Reactor autopilot. You will also need the unbalanced kit for the pump. Once installed measure for your hoses. Seems like an easy install. My only concern was how the cylinder mounted but seastar tech said that is the way to go. I ordered the cylinder and it will be here today. I will let you know how it goes. No matter what helm you go with you cannot use a seastar Pro helm. Those are for Balanced cylinders only.

Helm $380
cylinder $400.
Reactor AP $2000-$2200
Pump $999
Unbalanced kit. $88.
Hoses $ ??????
 
Cylinder posted is going to work great here.
 
Do not use Octopus! I tried it and it was a complete bust. Had 3 different people work on it with no results. Sent it back to the company to see if it was defective. They returned it and said it was ok. I am moving on and will just trash it.
 
I sent back my OCP unit and had it tested and it came back as good. After a little tuning on my AP with the gains the unit performs great. Just posting my experience.

Tooner keep us posted with pictures of your modification you may have solve the power assist AP problem for a lot of boaters.
 
pepper said:
Do not use Octopus! I tried it and it was a complete bust. Had 3 different people work on it with no results. Sent it back to the company to see if it was defective. They returned it and said it was ok. I am moving on and will just trash it.[/QUOT


I went through the same thing with Octopus. many times on the phone. many hours trying to get it right. They finally agreed that something was wrong with it.
Click to expand...
 
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2000SEARAY280SS said:
I sent back my OCP unit and had it tested and it came back as good. After a little tuning on my AP with the gains the unit performs great. Just posting my experience.

Tooner keep us posted with pictures of your modification you may have solve the power assist AP problem for a lot of boaters.
Click to expand...

I'm glad it worked for you. mat have worked for me if I gat a good one. But I was too frustrated to continue with it.

I will keep progress posted. Looks like an easy swap. I'll try to get pics of the cylinder area but it's kind of tight down there.
 
mechanical steering is harder to steer. power assisted mechanical steering is easy to steer. hydraulic steering is easy to steer. Power assisted hydraulic steering is the easiest to steer.
Auto pilot works the best with the hydraulic system. So if you want to add autopilot and you have mechanical steering, you may want to convert to hydraulic steering.
 
This is the mechanical steering cable attached to the power assist unit. Loosen the silver nut. Remove the cotter pin and pin from the end and slide the cable out.

 
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Slide the new hydraulic cylinder in where the old cable was and tighten. Pull the ram out to the proper length and attach with the pin and cotter pin. That's it. You do not have to touch the stock hydraulic assist unit. I wanted to see how this was going to fit up before I ordered the rest of the stuff needed... More to come

 
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This is the till end where the cylinder ram connects to. The pin on the left is the factory power assist. The pin on the right is where the new seastar ram connects. total install time so far about 20 minutes.

 
Removed the mechanical helm today. Now just have to wait for parts to come.
 
UPDATE:

I have everything installed including the garmin reactor autopilot. Everything works great. Not hard to install.
About a day including AP
 
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Just spotted this post while doing some research on alternate steering systems. My 85 Amberjacks steering is locked up and since its the original, its time for an update since they don't make these cables anymore. Not exactly sure what all types are better than others between the different mechanical systems or the hydraulics or what type will work on my boat. Didn't really want to spend a lot of money right now but am leaning towards the same Sea Star hydraulic system that the OP used. Just wish they would sell them in a kit like the outboard versions. I may ad an auto pilot down the road but right now just need to get the boat launched. Didn't even realize I had a problem till I started to launch her this weekend. Just another B.O.A.T. moment I guess ;)
 
Hello NH TOONER . How is work your new system ? Is it easy ? Difference with old Mecruiser system ? What is free movement on steering wheel ? Is it smaller that before ?
 
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