trolling motor thrust comparison

[MajBach]

Hi all. I have a couple of questions about my rollong motor. I used to own a small 14' w/ 18hp and had a 29lb thrust electric. This thing pushed the boat really well-upwards to 3.5 mph on gps. I now own a 17' DC w/ 90hp - it weighs about 4 times the other boat - and it has a 50lb bow mount. I'm not satisfied with how well it pushes the new boat. even a slight breeze and it struggles into the wind. I also notice that when watching the prop wpin out of the water, it doesnt appear to spin nearly as fast as my old one. Granted however, one was a motor guide this one is a minn kota.<br />I'm wondering if there is a way to utilize the power a little more. On my old boat, the 4' wires for the electric motor hooked up directly to the battery. On the current boat, there is a bow mount electrical panel and the wires leading up to it from the battery are smaller guage and at least 8' long. No doubt this robs a little voltage. The boat came with another set of wires for a 24 v system. I am wondering if doubling up the wires in parallel might allow better current flow. ( I beleive the voltage drops becasue the electrical panel on the boat has a battery level meter that never shows more than 60% charge even when the [new] battery id fully charged). <br />Also, we all know that prop selection on an o/b can greatly affect how it runs. Is is possible that my electric has to coarse a prop? Are there finer pitch props for electrics?<br />Thanks in advance.<br /><br />MajBach<br />One final note: Saved up and bought one of those co-pilot remotes. If you are considering one, it's proven to be a great little toy.

 

[Omega-1]

Re: trolling motor thrust comparison

Maj Bach,<br />It sounds to me like your current trolling motor is not getting enough power to operate efficiently. I would suggest that you look up the recommended size power wire for that motor, and fit it with a proper wire size. You may need a #8 wire as a power source, connected directly to a trolling motor battery of recommended amperage and voltage to ensure proper efficient function of that motor. I doubt that the prop is the problem with your engine. <br />If you have improper wire size and subvoltage, you will probably eventually damage your motor and overheat the wiring with a potential electrical fire on board. <br />The resource for proper wire size and battery characteristics should be available in your motor's owner's manual, or from the manufacturer or its dealer. Good luck, be safe, do a proper job with the specified materials.

 

[moondok]

Re: trolling motor thrust comparison

If you are willing to play a little, I would also suggest replacing the wire between the battery and electrical panel. Go with 6 or 8 gauge. You can never go too big. You may find that the panel shows a higher charge. Someone may have put that panel on there to keep from having to use more than one battery, or it's possible there just isn't enough room for a large trolling battery.<br /><br />As a side note, if you only have one battery on that boat, I seriously suggest getting another large marine battery. It never hurts to have 2, and you may get a much longer run time for that trolling motor.<br /><br />Good luck and post back to let us know what's happening.

 

[MrBigStuff]

Re: trolling motor thrust comparison

Originally posted by MajBach:<br /> ( I beleive the voltage drops becasue the electrical panel on the boat has a battery level meter that never shows more than 60% charge even when the [new] battery id fully charged). <br />

Time to invest $20 in a DVM. Using a volt meter, you can verify if you have a significant voltage drop from the battery to the motor. It could be connections or wire gauge or a combination of the two.<br /><br />Are you positive it's a 12 volt motor?<br /><br />I have a 12VDc 50lb Motor Guide on my 17' fiberglass bass boat with a 135hp OB. It pulls that rig quite well even in stiff winds.

 

[MajBach]

Re: trolling motor thrust comparison

thanks for the reply guys. never thought about using the multi meter - obvious check. I did double up the wires with the spare I mentioned and noticed a slight improvement. Theoretically, running two pairs in parallel should help. I'll double check with the MM. BTW, the guage wire from the trolling motor is the same diameter that runs from the plug on the motor to the motor itself ( built in wires). I don't see any other way of hooking up the motor directly - have to go thru the panel unless i cut wires.<br />Yes, it is a 50lb. not only does it state this but comapring the armature casing to other motors would suggest this.