Islander 268 and Garmin Reactor 40 autopilot

Gscheer

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Greetings!
I’ve read several posts regarding autopilot installs, but they’re different autopilots than what I’ve ordered.
Has anyone installed the Reactor 40 in an Islander? I’m 2.5 hrs from where my boat is slipped. I’m trying to get a general idea before this weekend when I’ll start my potential layout.

I appreciate your knowledge.

Greg Scheer
2001 Islander 268
 

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Greetings!
I’ve read several posts regarding autopilot installs, but they’re different autopilots than what I’ve ordered.
Has anyone installed the Reactor 40 in an Islander? I’m 2.5 hrs from where my boat is slipped. I’m trying to get a general idea before this weekend when I’ll start my potential layout.

I appreciate your knowledge.

Greg Scheer
2001 Islander 268
I put a reactor 40 in my 228. I have mixed feelings about it. When it works, it is *awesome*, one of the best upgrades I've done.

OK, so the downsides. Don't get shadow drive unless you have power steering. Shadow drive shuts off the auto pilot when it thinks you are steering. I don't have power steering, my power comes from the steering wheel. Which is tight, I found the nut on the engine that controls how stiff things are. If I loosen that enough that steering is easy, well, the currents, wind, whatever that pushes the engine around, shadow drive thinks I'm steering when I am not. That's a little bit annoying.
The biggest annoying thing about Garmin auto pilot is it loses it's mind a bunch. If you set a course and 30 seconds later engage the autopilot, or you set a course and you are not 99% on that course, when you engage the autopilot it will swing the boat to get on course and then go way past the course. That part of Garmin sucks.

So what do I do? Most of the time I'm on heading hold, that works fine. When I want to go to a waypoint (crabbing) or wherever, I set the course but then before I engage auto pilot, I get the boat up to speed and get on the line, then engage.

I love my autopilot, it is like having 80% of a deck hand on board, but I'm realistic about what it can do. If I were to do it all over again, I'd research who has the best auto pilot, does it work with Garmin, maybe I'd get something else.

Oh, another thing I love about it is pattern steering. When running a lot of lines out back, you need to do a perfect half circle, it will do it.

The other thing I'd say is get the dedicated display.
 
I put a reactor 40 in my 228. I have mixed feelings about it. When it works, it is *awesome*, one of the best upgrades I've done.

OK, so the downsides. Don't get shadow drive unless you have power steering. Shadow drive shuts off the auto pilot when it thinks you are steering. I don't have power steering, my power comes from the steering wheel. Which is tight, I found the nut on the engine that controls how stiff things are. If I loosen that enough that steering is easy, well, the currents, wind, whatever that pushes the engine around, shadow drive thinks I'm steering when I am not. That's a little bit annoying.
The biggest annoying thing about Garmin auto pilot is it loses it's mind a bunch. If you set a course and 30 seconds later engage the autopilot, or you set a course and you are not 99% on that course, when you engage the autopilot it will swing the boat to get on course and then go way past the course. That part of Garmin sucks.

So what do I do? Most of the time I'm on heading hold, that works fine. When I want to go to a waypoint (crabbing) or wherever, I set the course but then before I engage auto pilot, I get the boat up to speed and get on the line, then engage.

I love my autopilot, it is like having 80% of a deck hand on board, but I'm realistic about what it can do. If I were to do it all over again, I'd research who has the best auto pilot, does it work with Garmin, maybe I'd get something else.

Oh, another thing I love about it is pattern steering. When running a lot of lines out back, you need to do a perfect half circle, it will do it.

The other thing I'd say is get the dedicated display.
You set the rudder gains? Mine stays on a perfect straight line and never over shoots. You are right tho how it goes straight to the go to line.
 
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I put a reactor 40 in my 228. I have mixed feelings about it. When it works, it is *awesome*, one of the best upgrades I've done.

OK, so the downsides. Don't get shadow drive unless you have power steering. Shadow drive shuts off the auto pilot when it thinks you are steering. I don't have power steering, my power comes from the steering wheel. Which is tight, I found the nut on the engine that controls how stiff things are. If I loosen that enough that steering is easy, well, the currents, wind, whatever that pushes the engine around, shadow drive thinks I'm steering when I am not. That's a little bit annoying.
The biggest annoying thing about Garmin auto pilot is it loses it's mind a bunch. If you set a course and 30 seconds later engage the autopilot, or you set a course and you are not 99% on that course, when you engage the autopilot it will swing the boat to get on course and then go way past the course. That part of Garmin sucks.

So what do I do? Most of the time I'm on heading hold, that works fine. When I want to go to a waypoint (crabbing) or wherever, I set the course but then before I engage auto pilot, I get the boat up to speed and get on the line, then engage.

I love my autopilot, it is like having 80% of a deck hand on board, but I'm realistic about what it can do. If I were to do it all over again, I'd research who has the best auto pilot, does it work with Garmin, maybe I'd get something else.

Oh, another thing I love about it is pattern steering. When running a lot of lines out back, you need to do a perfect half circle, it will do it.

The other thing I'd say is get the dedicated display.
Thank you for replying. Where did you locate the pump? Did you install a Smartpump?
 
Thank you for replying. Where did you locate the pump? Did you install a Smartpump?
Yeah the reactor 40 smart pump. Love it. I have the sailfish. It’s startboard side of the mid berth. Perfect spot for it.
 
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You set the rudder gains? Mine stays on a perfect straight line and never over shoots. You are right tho how it goes straight to the go to line.

Yep, i would guess he has a setting wrong.

Thank you for replying. Where did you locate the pump? Did you install a Smartpump?

You need a well accessible space of about one six pack on top of the other, search the dimensions and installing instructions on the Garmin website.
No idea about your boat, my Reactor 40 is in the smaller locker below the big battery locker and door has about the size of 2 six packs.
You need a space where you can work well, mine is not as on level of floor of the center console and who installed it was probably a dwarf.
Best would be under the dash board or nearby, but not limited to that but may need longer hoses then.
You need also a space without electronic and magnetic interference for the CCU, the Course Computer Unit what is also the heading sensor and the ECU what must be installed near the pump, both are shown below (the brass valve is the ShadowDrive valve you may wan't or not)

I don't have ShadowDrive what is a safety feature as you can turn the wheel in a emergency to disable the AP, i don't have it and have to stand up and push the button on the GHC20 display what may take precious seconds to avoid a accident. As luckydudes wrote, if there is a possibility that something/someone turns the wheel the AP will be unexpected disabled, however i did not heard complaints of similar problems. Heading hold is particularly nice for solo fisher like me as i can set the course and boat holds it while i to drop the trolling rods.

Chris
Bildschirmfoto 2025-06-19 um 08.15.05.jpg
 
Yep, i would guess he has a setting wrong.



You need a well accessible space of about one six pack on top of the other, search the dimensions and installing instructions on the Garmin website.
No idea about your boat, my Reactor 40 is in the smaller locker below the big battery locker and door has about the size of 2 six packs.
You need a space where you can work well, mine is not as on level of floor of the center console and who installed it was probably a dwarf.
Best would be under the dash board or nearby, but not limited to that but may need longer hoses then.
You need also a space without electronic and magnetic interference for the CCU, the Course Computer Unit what is also the heading sensor and the ECU what must be installed near the pump, both are shown below (the brass valve is the ShadowDrive valve you may wan't or not)

I don't have ShadowDrive what is a safety feature as you can turn the wheel in a emergency to disable the AP, i don't have it and have to stand up and push the button on the GHC20 display what may take precious seconds to avoid a accident. As luckydudes wrote, if there is a possibility that something/someone turns the wheel the AP will be unexpected disabled, however i did not heard complaints of similar problems. Heading hold is particularly nice for solo fisher like me as i can set the course and boat holds it while i to drop the trolling rods.

Chris
View attachment 37334
Thank you, Chris. This autopilot does not come with hydraulic lines so I’ll likely have them made.
 
Thank you, Chris. This autopilot does not come with hydraulic lines so I’ll likely have them made.
Yes, i know that he comes without hydraulic hoses, same as steering cylinders:
Just order the correct length of hydraulic hoses in all lengths from Teleflex for example, if Garmin sells them too then get the ones from Garmin.
You can also have them made by erath mocing companies for example, however keep in mind that connectors may be different

Proper Hydraulic Fittings for the Garmin GHP Autopilot Pumps

I personally would not have hydraulic hoses made by others if i don't need to, but i have had it made as i needed too when in Costa Rica.

Chris
 
Its not an islander but I do have a Garmin reactor 40 and smart pump in my 305. I installed it 5 years ago and is the best autopilot I have had in any boat. It holds course at any speed and in any sea state. I have had to go through the setup phase a few times, but nothing compared to a simrad I had on an other boat. In my boat the smart pump is located in the rear bilge next to the generator. I choose that spot because it was close to the batteries and the T- connection for the hydraulic steering. Plus there was plenty of space there. The computer and shadow drive are mounted under the dash, on the wall of the tube for the electronics pod.