Autopilot compatibility

Good evening all, our vessel has a Furuno RDF-139 radar with GPS and I would like to add an autopilot, the steering is chain driven to tiller...could anyone suggest which autopilot would work ? The boat is around 30,000 pounds. I have checked Furuno's website and it tells me nothing...thanks again...

For a boat that heavy you would need one with a rotary drive and sprocket with connecting chain to and accessory sprocket on the steering hub behind the helm bulkhead for sure. They work extremely well, but are more expensive than other types which fit most hydraulic systems.
A wheel mounted system would struggle on your boat, and would not be recommended. The beauty of the above sprocket and chain drive is it does not work on the rudder quadrant, so takes advantage of the gearing built into the chain and rod mechanical system, is out of the steamy lazaret, and you never have fluid leak issues.

Possibly WH Autopilots.

WH Autopilots

I really think the AP is an item that you want to buy the best you can afford. It might save your life. Let's say your injured or limited and in rough weather. The AP's ability to steer your boat might be critical to your safety/comfort. You need to consider the AP to be a mate on board and choose accordingly. If your strictly inland then this consideration might not apply however.

All of the major autopilot manufacturers, Raymarine, Garmin, Simrad, etc have actuators, whether chain/sprocket or hydraulic rams operating on the steering post, that will work.

Concentrate on the mfg, not the actuator. Any of the three above will work well.

Try this

Raymarine Type 2 Rotary Autopilot Drive 12v - M81136

I saw one at the Seattle Boat Show that a neighbor was thinking of buying. I will see if I can find the information in my 1 ft stack of misc boat stuff.

My boat had push/pull cable steering (terrible). Installed Hydrive hydraulic system purchased direct from Hydrive and bought new Octopus autopilot pump and used Raymarine autopilot on Ebay. Entire system installed in one weekend for under $3,500.00 .... perfect !