Trolling motor surging?

On my last trip out my trolling motor acted pretty funny. I had charged it after the previous trip, and then again over this weekend before I went out Sunday night. The motor is probably 9 years old and I think the batteries are around maybe 4 years old. When I went out, it seemed like the motor was only able to do “all the way on” so to speak… full torque. If I turned it down it would either not run at all or surge from full torque to barely running and then back to full torque.
Any thoughts on this? I was thinking maybe a battery but I dunno.
Thanks in advance

2004 Action Craft 1820
Flats Master SE

I cannot speak to the way of fixing this (other than suggesting that this isn’t a battery related issue)… but I have read a number of forums where guys have taken 5-spd trolling motors and turned them into infinite variable-speed by putting this modulator on the + side (between the motor and the battery). You set the motor to speed 5, and adjust your speed with the knob on the modulator.

http://www.ebay.com/itm/160736035041?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649



“Sire, it belongs in truth to the Church of God, in whose name I speak, to endure blows and not to inflict them. But it will also please your Majesty to remember that she is an anvil that has worn out many hammers.”…Theodore Beza

What is that thing? like a replacement for the speed adjustment handle? I forgot to mention that it’s a min kota riptide 72… if that matters any.

2004 Action Craft 1820
Flats Master SE

More or less, yes it is. It’s the same technology they use in the variable speed motors— you will get far, far more speed control than you had on the 5-speed, and when using the lower speeds, you’ll get far longer battery life because of the way it regulates the speed.

Please note that the one I linked you to is for a 12 volt motor. Yours is probably 24 volt, in which case you’d need a 24v compatible PWM.

This one should work-- looks to be the same unit but with 12-24v input capabilities.
http://www.ebay.com/itm/80A-PWM-PULSE-WIDTH-MODULATOR-CONSTANT-w-AUTO-PROTECTION-TO-24V-12V-HHO-CELL-/160736038457?pt=Motors_Car_Truck_Parts_Accessories&hash=item256c9d4e39&vxp=mtr

Read this thread. I have not personally used this, but nearly did because I was offered a nearly-free 40lb thrust motor a while back, but I opted for something brand new and got a variable speed. I now would NEVER buy anything but a variable speed, it’s a sweet option.
http://www.tinboats.net/forum/viewtopic.php?f=5&t=26975



“Sire, it belongs in truth to the Church of God, in whose name I speak, to endure blows and not to inflict them. But it will also please your Majesty to remember that she is an anvil that has worn out many hammers.”…Theodore Beza

hmmm… so you’re thinking it may be a problem with the speed control, more or less an internal issue? I’ll have to look into this some more, but the little guy on my shoulder is claiming this could be a way to talk the wife into an i-pilot. I was really hoping for a battery issue tho.

2004 Action Craft 1820
Flats Master SE

Well, if you can afford an I-pilot, then go for it lol. Best thing connected to a battery and on the water, if you ask me.

But yes, my novice opinion is that it sounds like an internal issue. Whatever is regulating the speed is getting bypassed into “full throttle”. So if it ever does “only full throttle” then that PWM module I linked you to would always work fine, since the motor has to be set to max speed for it to work right anyhow.



“Sire, it belongs in truth to the Church of God, in whose name I speak, to endure blows and not to inflict them. But it will also please your Majesty to remember that she is an anvil that has worn out many hammers.”…Theodore Beza

It sounds like you may have worn brushes. I replaced a set on my last motor. Not extremely hard to do but an extra pair of hands helps.

17 Trophy-Merc 90

Sounds like classic brushes to me, I bowfish alot and use an 80lb riptide and replace the brushes a couple times of year due to the abuse put on the motor (running wide open, weeds etc…)

“Wow! Your daughter is just as good as your wife!!”
“Lets pull the Venezuelan Bubbler!”

“Queen Anne’s Revenge”
129’ 36 Guns 113 souls

your problem sounds a lot like mine. I posted a while back about getting a new trolling motor. I still want to do that to get one with more thrust but now I’ll look into fixing my old one as well.

is that motor a 5 speed or is it “variable”

www.teamcharlestonmarine.com
www.joinrfa.org

Is it a Co-pilot? I have had two go out on me and that is the way it acted.

Mine is a five speed motorguide. At first it started cutting off and then back on abruptly only on the highest speed. Now it does it on the 3 higher speeds but is fine on low.