I am thinking of upgrading my Raymarine wheel pilot to a new "type 1" linear drive. If you have upgraded your 35.5, I would appreciate your comments on how your installation went, especially in regards to mounting the drive unit. Did you use a long or short shaft? How sturdy did you brace the drive and has it held up well? Also did you custom make the arm to the rudder or just hook it up to the drive wheel. Your insight would be greatly appreciated.
Linear drive for a legend 35.5
- Thread starter windwagon
- Start date
Linear for 37.5 Hunter
We purchased a Linear drive with ST 70 autopilot for our 1995 Hunter 37.5. Not sure if the layout is the same, but we love our Linear drive and it handles the boat with ease. Problem with wheel drive units is the motor unit is not strong enough to handle the boats weight in 15-20 knots of wind. Check the displacement weight of the boat and add 20% to get the correct weight the autopilot will handle. .We drilled a hole beneath the cover plate for the quadrant. Reversed the boot and connected the linear drive to the quadrant. We secured the drive unit to the bulkhead in the aft locker.
When I talked to Hunter concerning the install, they told me the boats were not built for below deck auto pilot. I found that very interesting when the boats signature was a cruising boat! Oh well, we love our boat; sail her on Lake Erie and hope to take the boat down the Erie Canal and out onto ICW.
Hope this helps
We purchased a Linear drive with ST 70 autopilot for our 1995 Hunter 37.5. Not sure if the layout is the same, but we love our Linear drive and it handles the boat with ease. Problem with wheel drive units is the motor unit is not strong enough to handle the boats weight in 15-20 knots of wind. Check the displacement weight of the boat and add 20% to get the correct weight the autopilot will handle. .We drilled a hole beneath the cover plate for the quadrant. Reversed the boot and connected the linear drive to the quadrant. We secured the drive unit to the bulkhead in the aft locker.
When I talked to Hunter concerning the install, they told me the boats were not built for below deck auto pilot. I found that very interesting when the boats signature was a cruising boat! Oh well, we love our boat; sail her on Lake Erie and hope to take the boat down the Erie Canal and out onto ICW.
Hope this helps
You must dock very near where I do. I am at Herl's. When it warms up, I would like to see your setup. I am pretty sure our quadrant system design is near identical. In the meantime I would like to contact you by phone or email. I plan to purchase sometime this winter. I am looking at almost the same system you installed. I have compatibility st60 questions I am hoping you can answer. Thank you for your help.
Don Habegger
Don Habegger
Chris / Bugsboat,
I have a new-to-me 37.5 also and the Autohelm ST-4000 it came with is kaput. It seems to me that this unit, or any wheel-mount unit, is not up to the task of steering a boat of this displacement anyway, particularly on the Atlantic shore of Long Island NY where I sail. I would love to see pics of your installation or any other guidance you could provide. Did you do the installation yourself? As you know, outside/cockpit locker space on this boat is limited because of the fabulous aft cabin, so giving up a lot of that space to the AP mechanism is not desirable. You are right this is a wonderful boat in almost all aspects, the best I have ever owned or sailed. Any help on this from anyone would be appreciated!
Neill
The linear drive is perfect for the Hunter 37.5; figure 16400+3280=19680 displacement weight. Too much for wheel drive units! Look at your quadrant and the lazarette; the space is kind of close, but if you are careful the hole can be drilled to attach the linear arm to the quadrant. Mounting the drive unit to the bulkhead can be a little tricky, but we were able to bolt thru to the propane locker, attaching support to the bulkhead. Don, we are located at Harbor Park Marina during the summer, but keep the boat at Catawba Moorings on the hard for winter. The boat is shrink wrapped, but spring is getting closer! We need to connect when spring gets here. If you know Annie at West Marine, she knows us well.
Jennie
Jennie
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I have a 1990 37.5 legend. I have been looking to add an autohelm. I have looked at the linear drive units. I was concerned about the lack of "waterproofness" of these units coupled with the exposed stern. Also, i will have to partially donate the port lazarette to the linear drive. Can you send pictures?
Ben
Ben
Nick,
Thanks for the .PDF. Now, I am thoroughly petrified to tackle this project
My boat's steering quadrant is a bit different than yours, but the concept is the same......partially exposed quadrant. My quadrant is just that......it is a large semicircle with stops on it, and I will have to pop into the port lazarette for the linear drive unit.
Ben
Thanks for the .PDF. Now, I am thoroughly petrified to tackle this project
My boat's steering quadrant is a bit different than yours, but the concept is the same......partially exposed quadrant. My quadrant is just that......it is a large semicircle with stops on it, and I will have to pop into the port lazarette for the linear drive unit.
Ben
Ben:
This is a scary install. Just remember that you can put on a boot (reverse the boot for maximum protection) on under the quadrant cover. That is where you will want to make your pilot hole for the install of the arm. Our boat is shrink wrapped for the winter, but I will take pics in the spring for everyone. I would take off the quadrant cover and look at the layout. The hole drilled for the linear drive arm and boot will lay just below the coaming for the quadrant cover. Hope this helps.
J
This is a scary install. Just remember that you can put on a boot (reverse the boot for maximum protection) on under the quadrant cover. That is where you will want to make your pilot hole for the install of the arm. Our boat is shrink wrapped for the winter, but I will take pics in the spring for everyone. I would take off the quadrant cover and look at the layout. The hole drilled for the linear drive arm and boot will lay just below the coaming for the quadrant cover. Hope this helps.
J
Does anyone know where you buy the rubber boot kit? Thank you for all the information. I think I can do this.
.
.
Auto store
I have seen them in Auto stores for sure.
The rubber boot is no big deal it's mounting the linear drive and making the
hole so double check and check and check over again before making the hole.
Nick
I have seen them in Auto stores for sure.
The rubber boot is no big deal it's mounting the linear drive and making the
hole so double check and check and check over again before making the hole.
Nick
Bugsboat,
Thanks!! I would like to see the photos. I will most likely go with a professional for the job, though.
Thanks!! I would like to see the photos. I will most likely go with a professional for the job, though.
You really should download the installation manual for the SPX pilots.
SPX-10, SPX-30, SPX-SOL Course Computer Installation instructions 87072-3-EN.pdf
On page 20 you'll find this:
So, it indicates your SPX-10 can drive a Type 1 linear drive.