Humminnbird/Minn Kota Problem!

[MaizeNBlue]

Ok I've gone round and round with both manufactures, dozens of calls, work and effort, with out a solution. So I will see if anyone here can help me. I purchased a 788DI for the front of my boat, works great until you engage the trolling motor. I have the transducer on the bottom of the lower unit. When I engage the trolling motor, the depth goes crazy, and the sonar and DI screens fill with electrical interference. Trolling motor is a Minn Kota Maxxum 80 24volt with US1, think its a 2005 or 6

Things both manufactures and I have tried:

Disconnect US1 at the head of the trolling motor
Yes the fish finder is powered on a separate battery
Isolate trolling motor power cables, I ran them through a rubber conduit.
Move trolling motor power cables to the other side of the boat
Ground trolling motor battery to main battery
Ground from skag on trolling motor to trolling motor battery
Sent power cable for the fish finder with a filter on it, think they called it a choke
Placed a piece carpet between transducer and lower unit
Replace metal clamps with zip ties

When I move the transducer 6 inches away from the lower unit...no interference shows on screen.

Thanks to anyone in advance who may have any suggestion to resolve this issue. My cell # is 734-478-1218 Thanks Grant

Just fyi.....old fishfinder was a Eagle that was US1 compatable...so never had a transducer on the lower unit itself.

[markgoetsch]

I just had my 788 installed and it has the same issue!  I used to have a x135 and it had zero issues.  My trolling motor is a maxxum pro 101 w/ US2 I was going to call them this week but I guess you just showed me it not just me.  Let me know if you hear anything.

[fasttrack]

I know HB has an interference kit available. Not sure if its the same thing as the power cable filter you listed. If not, I think that's the way to go. Do you subscribe (free) to the Yahoo Groups HB Forum? If not you should consider it - ya just get a daily email of recent Q&A's. Greg that moderates it is usually very helpful. Good luck, and let us know what happens!

[MaizeNBlue]

No mark your not alone....let me know if they try something different with ya and the outcome.

Thanks fasttrack....I'll give it a try there as well.

[Durand Dan]

Just a thought. If the Trolling Motors you have are a little older maybe the armature brushes or brush springs are worn and do not have 100% contact all the time causing some type of interference.

[MaizeNBlue]

I like your thinking Dan....a couple of weeks ago when I put the unit on and got the interference the first time out........I thought the problem was coming from the old US1 transducer....So being the man I am (not a very bright one) I went home and figured I could disasemble the lower unit and unplug it.....well I was not only wrong but pulled it apart to hard, and locked the springs out....had to pay to have it put it back together...had the guy check everything since it has some use on it....said everything was fine.

[Waterfoul]

Strange that no one I know is having any of these issues with the 787ci (me) or 788ci (two of my buddies).  Sounds like it is something to do with the frequency that the down imaging transducers are operating at with the new di units.

[markgoetsch]

mine isn't a DI unit.

[Puma]

Minn Kota has two fixes for this from what I have seen.  One is to ground the brush plate of your trolling motor and there is a kit for this, the other kit they can send you has a ground wire from the negative post of your trolling motor battery to the negative post of your starting battery with a 2 amp fuse inline.

I ordered a new brush kit and armature for my Minn Kota last year and it came with instructions on how to ground the brush plate, but I can't locate them.  Hope this helps.

[MaizeNBlue]

Thanks for the info......I talked to HB yet again this morning.....I asked them about the interference kits..said the PC 11 cable is the aka Choke...that they sent...is there solution for the DI...they save a different kit they offer with chokes and some ring thing but only for the SI units.They also had me check the fuse in the trolling motor head...problem being, when I looked...there wasn't a fuse there lol.  I then talked Minn Kota once again...they recommended trying a internal ground for the lower unit.....so now they want me to pay to try to get  there stuff to work grrrrrr.

[markgoetsch]

I also checked for the fuse but it didn't have a fuse.  But my power wires were  slighty melted and slightly caroaded.  I cleaned up the connections and retaped and the problem seems to have disappeared!

[MaizeNBlue]

Happy for ya Mark....my journey marches on.

[markgoetsch]

Thanks and I hope your journey comes to an end very soon.

[Firefighter Jeff]

Well, unfortunately Maize, I am in the same boat as you.  Gave the 788 ci DI its first work out and It's fubr also.  When I use the trolling motor, most times the depth jumps to 30 40 50 etc feet and the view changes range.  Then it settles back down after letting off the power.  These electronics are driving me nuts.  I bought a 898 at the same time.  Took me three tries to find a Ram mount that would work right on the 898.  Then find out I can't flush mount the 788 without a flush mount kit. $24 plus shipping.  Get a ethernet cable, then find out I can't use it to connect the 788 unless I buy a adapter $23 plus shipping, Now I have the interference problem, I'm sure these so called fixes they offer aren't free. I'm afraid of the hoops I'm gonna have to jump through to get the 788 to work like it should.  Grrrrrr  ok, I feel a little better.

[Waterfoul]

There has got to be some simple, underlying cause that all of you are experiencing.

What model trolling motors are you guys running?  Do they have big enough power cables??   Are all the connections tight and corrosion free?  Do you have your Humminbirds on their own dedicated circuit?  Are you drawing your Humminbird power from the starting battery and NOT the trolling motor batteries (this is a must)??

I have a MinnKota Fortrex 80 lb and a 787ci and have never had an issue.  Fastrack has a MinnKota Maxum 80 and a 788ci and has no issues.  Edyer1054, same set up as Fastrack, no issues.

[Firefighter Jeff]

There has got to be some simple, underlying cause that all of you are experiencing.

What model trolling motors are you guys running?  Do they have big enough power cables??   Are all the connections tight and corrosion free?  Do you have your Humminbirds on their own dedicated circuit?  Are you drawing your Humminbird power from the starting battery and NOT the trolling motor batteries (this is a must)??

I have a MinnKota Fortrex 80 lb and a 787ci and have never had an issue.  Fastrack has a MinnKota Maxum 80 and a 788ci and has no issues.  Edyer1054, same set up as Fastrack, no issues.

   I have a Minn Kota Maxxum 80.  It must be the Down imaging.  I've had two Eagle graphs at the bow previously and no problems at all.  You ask a lot of questions Mike.  I have to do some homework.  The graph and wiring was installed by the dealer I bought it from.  I just used the same power source.  Some have suggested that people with this problem should check some fuse or connections in the TM head.  Apparently if there is a problem it didn't affect the old graphs??  Or are guys adding new graphs instead of replacing one like I have?

[Mike Nolan]

You sound like you know what time it is as far as tracking things down.  One not so obvious thing you might want to look at is too see if you have broken insulation in your transducer cable.  Even though the unit is new, you might have cut the insulation cable while installing it or it might have been broken coming out of the box.  I had a similar problem and it took me a while to figure it out, I happened to check my trolling motor when it was kind of dark out and could actually see the arc coming from the transducer cable.  Good luck.

[huston]

I have  the 898 SI and 788 DI also and yesterday was my maiden voyage with it. I have the MInn Kota Maxxum 74lb with the built in sonar. My biggest problem yesterday was the weather and trying to understand how HB stuff works. You don't get a manual with this, so either you print one or ask HB to send you one in which they will for free. I installed mine myself and so far so good.  I was worried about that 788 on the front too.  I really didn't play with it alot yesterday since I was fishing canals. I didn't notice any problems with the trolling motor and 788 yet but I need to operate it more to see. I was worried about that thru hull transducer I mounted in the rear of my boat and if it would leak. Lowrance/Eagle operates different than HB and that's my problem so far. I did catch fish in and around the marinas in anchor bay but water was muddy  and temps were 44 degrees. There are HB forums online and on other fishing websites that deal with these HB issues. Let's keep this going until it's resolved.

[thedude]

i had a terrova and maxxum and they both made my 727 on the motor go skitzo.  Any variable speed trolling can create interference because of the pulse-draw method of powering the motor. It creates EM interference that is emitted via the power cables for the TM. If you have a 20' boat, figure that you have 24' antenna for broadcasting EM interference.

i got the interference kit from HB and life was good.

As a side note, I would live and die by humminbird and minn kota - however you couldn't pay me to use US2 as i've never had it function correctly for any significant duration.

[Firefighter Jeff]

i had a terrova and maxxum and they both made my 727 on the motor go skitzo.  Any variable speed trolling can create interference because of the pulse-draw method of powering the motor. It creates EM interference that is emitted via the power cables for the TM. If you have a 20' boat, figure that you have 24' antenna for broadcasting EM interference.

i got the interference kit from HB and life was good.

As a side note, I would live and die by humminbird and minn kota - however you couldn't pay me to use US2 as i've never had it function correctly for any significant duration.

Keeping in mind there are no dumb questions.. lol  What is this US2 you are talking about ?