Trolling motor only operates at full speed

[MrBookworm]

Help! I have a pontoon boat with twin electric trolling motors mounted on the back (residential electric only "lake"). The motors are probably 15+ years old as the pontoon came with the house when we purchased it last year and the markings have all faded off the motors. Everything was working fine until I tried to run the motors this weekend. They had been sitting unused for about 3 weeks.

One of the motors will only operate at full speed in either forward or reverse. The other motor works fine. I have a rotary speed dial to control the speed and a 3 position toggle switch for forward - off - reverse. The rotary dial and toggle switch control both motors. So, as soon as I flip the toggle switch to forward or reverse the one motor immediately goes full blast in the proper direction regardless of the rotary dial setting.

I switched the control wire/connector between the motors and the problem remained on the same motor. So, I think I can rule out a wiring issue and it looks like a problem with the motor. I'm assuming I need to look in the motor housing? Any ideas of what to look for or what the problem may be?

Dean

 

[MrBookworm]

Re: Trolling motor only operates at full speed

UPDATE: I pulled the cover off the motor top and it looks like the control board is fried. There is smoke marks on the underside of the cover and I can see where the board has burned a bit. The control board label says "234-4005" with what looks like a date below it of "07/1995".

When I do a Google search for "minn kota 234-4005" I get one hit for this site: http://www.evin.nl/2005/interne links/minnkota/handleidingen/overige (oud)/3-1 en 4-4 hp.pdf with a parts diagram and part 48 looks exactly like the board for my motor. This must be a Minn Kota 4.3 HP/S motor probably model year 1995.

Does anyone know where I can get a replacement board?

Dean

 

[Silvertip]

Re: Trolling motor only operates at full speed

I think you have a 43 pound thrust motor not a 4.3 HP. As for where to get the board, follow the instructions at the top of the page of the parts list (in the USA, from MinnKota, Mankato, MN).

 

[MrBookworm]

Re: Trolling motor only operates at full speed

I called Minn Kota and they sold me a replacement control board, part number 2774001 (substitute for the 2344005). Hopefully this will solve my problem.

After further research I think I have a 24v 70# thrust 1996 model year Minn Kota. Well, I know it's a 24v because I have four 6 volt batteries wired up to be 24v feeding the motors.

Dean

 

[MrBookworm]

Re: Trolling motor only operates at full speed

I called Minn Kota and they sold me a replacement control board, part number 2774001 (substitute for the 2344005). Hopefully this will solve my problem.

After further research I think I have a 24v 70# thrust 1996 model year Minn Kota. Well, I know it's a 24v because I have four 6 volt batteries wired up to be 24v feeding the motors.

Dean

Ok, now I need some more help. The new board is different than the old one in 2 different aspects.

1. The new board only has 1 24v input and 1 output to the motor. The old board had 2 (yes, it was 24v on both). I don't have any problem re-wiring from the batteries to provide 1 24v input to the new board and 1 output to the motor. Is this going to be a problem?

2. The old board had 6 wires running to the controls. The new board only has 3 wires in the ribbon cable. Any ideas?

Here are some pictures:

Old Control Assembly Board​

New Control Assembly Board​

 

[Chris1956]

Re: Trolling motor only operates at full speed

Sounds like you need to contact the manufacturer. If they made a replacement with the same function, but a different form, they need to provide instructions on how to modify you motor to accept the new part.