Improve your grounding

I hate electrical diagrams SOOOOO much.  It looks to me like what i am thinking is what your diagram is showing but im still not sure.

get a extra ground wire and run it from the motor to the frame and your good i think

I had planned on that...then regrounding the battery to the frame

chuddly wrote:

I hate electrical diagrams SOOOOO much.  It looks to me like what i am thinking is what your diagram is showing but im still not sure.

Yes, I think that you are on the right track. I edited your pictorial, in order to show the wire harness, which was not shown. hopefully these new pictorials show what I am trying to say about re-routing the pigtail? Re-routing the pigtail is important because it removes the pathway where that pigtail WILL burn up IF you lose the factory connection from battery to engine case AND apply a heavy current load to the frame ground path.

Got it...easy enough.  Its exactly what i thought.  I was just going to beef up the ground from the battery to the frame also (which couldnt hurt).  Sorry ....im not really that dumb when it comes to wiring its just electrical diagrams and I dont get along AT ALL

chuddly wrote:

Got it...easy enough.  Its exactly what i thought.  I was just going to beef up the ground from the battery to the frame also (which couldnt hurt).  Sorry ....im not really that dumb when it comes to wiring its just electrical diagrams and I dont get along AT ALL

Yes, an additional ground from battery negative terminal to the frame will not hurt at all. Remember, bigger wire is better wire for those connections. The important thing that I am stressing is to get the wire harness disconnected from the battery negative terminal.

Yeah, schematics are indeed another foreign language to learn. It is amazing what you can figure out if you can understand them though. I'm glad that my tweaking with your pictorial got us clearly on the same page. Have fun, and watch your fingers using those sharp tools

Hay steve thanks for all the info. Is this a thing I need to do to the 2008 450's mine looks a little diff.and not sure THANKS John

JBFIREMAN wrote:

Hay steve thanks for all the info. Is this a thing I need to do to the 2008 450's mine looks a little diff.and not sure THANKS John

Hmmm, A quick look at the 2006 service manual wiring diagram shows that the battery connection area is identical. What sort of differences are you seeing?

Don't see the small wire at neg lug but I will look closer. THANKS  I think they would all be the same so it must be me not seeing it. ITS FRIDAY so lets all load up and get ready to ride

Got it this weekend easy job THANKS.

hey steve do you happen to know what size bolt fits into the threaded hole on the frame where you ground from the engine.  does the battery  need to be grounded to the engine or can you just ground straight to the frame?

txgrown1404 wrote:

hey steve do you happen to know what size bolt fits into the threaded hole on the frame where you ground from the engine.  does the battery  need to be grounded to the engine or can you just ground straight to the frame?

I don't remember exactly, but M5 maybe, or M6 probably. Where I grounded already had a bolt there for attaching a clamp for the metal water line, if I remember correctly. So you will likely be able to use the same bolt. Make sure that you scrape the paint off around that threaded hole in the frame and make sure that all of the parts that you stack up are clean bare metal all the way up the stack. Also, put a generous coating of silicone dielectric grease on all of the surfaces and the threads of the bolt so that it will not corrode down the road. I recommend 10 gauge, even bigger is better. 10 gauge wire is not something that everybody has laying around and crimp terminals as well, so running 2 separate 12 gauge wires (parallel connection) is as good or better.

The battery negative terminal is already connected to the engine via the black 6 gauge cable that you are going to piggy-back onto at the engine case. It is there to serve as the return path for the starter motor feed, so it is really beefy. Review the picture that I posted; it is mostly hidden by the other wires that I have stacked onto it but it is there to (barely) see. Use the silicone dielectric there too.

The only part about this write up I understand at all is the extra ground from the engine to the frame hole the water hose clamp uses, and I think I understand the part where Chris H added an extra bat cable wire from the - post to the frame, so now he has 2 - bat cables from the - post to the frame?

Is this a correct understanding so far? If so is this sufficient enough for me to leave it at this, without trying to figure out the pigtail part? I hope so cause that one has me all sorts of lost. I am not a fan of electrical stuff at all. I'll stick to my machining instead! lol

kris55 wrote:

The only part about this write up I understand at all is the extra ground from the engine to the frame hole the water hose clamp uses, and I think I understand the part where Chris H added an extra bat cable wire from the - post to the frame, so now he has 2 - bat cables from the - post to the frame?

Is this a correct understanding so far? If so is this sufficient enough for me to leave it at this, without trying to figure out the pigtail part? I hope so cause that one has me all sorts of lost. I am not a fan of electrical stuff at all. I'll stick to my machining instead! lol

Extra ground connections do not hurt. Very heavy wire(s) are what you want.

I'll try to explain the reason that I am advocating and the reason for cutting the wire harness pigtail away from the battery negative cable clamp and reconnecting it to the frame instead:

A common failure mode that can and will burn up the wire harness grounding wire is a failure of the ground battery cable connection at the engine case. This connection can fail from corrosion between the cable lug and engine case, or from simply becoming loose. It does happen. The problem this causes is a loss of the intended ground path of the starter motor to the battery negative terminal. The engine case is not deliberately connected to the frame and its connection to the wire harness wiring is accidental, through things like small gauge wire to sending units and the like (if any at all). Without the proper ground path to the battery negative when you crank the engine it draws a huge current and has to find an alternative path to the battery. This turns out to be through that little pigtail wire and it's grounding wire in the wire harness. It cannot handle the current and melts down. When you disconnect the pigtail from the battery the starter current cannot find an alternative path to the battery, so the wiring is saved. The problem is that the electrical system has lost its ground altogether, so we attach the pigtail to a known good grounding point on the frame. Another problem then becomes obvious, and that is the frame is not connected to the battery negative terminal, so we put a very heavy wire between the engine case ground cable connection point to the frame. The electrical pathway is now completed and all works as it should.

The reason that I advise making the heavy ground connection at the engine case rather than from battery negative terminal to frame is related to the possible failure of the battery negative cable connection to the frame and those accidental ground connections that I was mentioning. When the ground connection to the engine case and the ground connection to the frame are siamesed together, the chances are better that both ground paths fail together. Ideally, the engine simply does not crank at all until you fix the bad connection at the engine case.

I realize that this is a bit convoluted, please do comment if it is not understandable or questionable.

All I can tell you is that it happened to me... unfortunately.

I was[un]lucky enough that not only did my pigtail connector melt but also the ground wire to the voltage regulator/rectifier. It was a HUGE mess. It took almost 2 weeks of late nights to peel back factory wire harness and insulation to trace all the damage. Trust me, you do not want this happening to your ride.

I have a little electrical knowledge, but nothing like SteveS or some of the other gurus on here. My buddy who also has a Rhino said if what happened to mine would have happened to his, he would have traded it in and ate the loss. The amount of electrical damage done was far beyond his skill level.

So if you don't think it would be fun to have your Rhino down for a couple of weeks; if you don't like the idea of cutting, splicing, clamping, and soldering dozens of connections; if that doesn't sound like a good time to you, then add two heavy ground wires like suggested. I used 6AWG. It is so simple and could possibly save you a lot of grief.

ChrisH wrote:

I used 6AWG. It is so simple and could possibly save you a lot of grief.

6 gauge will certainly do the trick! The problem is cutting the wire and then crimping on the ring terminals (called lugs when they get this big). It takes a really hefty tool to do the crimping. I modified a copper tubing swaging vise (a pair of heavy steel parallel bars with half moon holes facing each other, meant to wrap around the tubing to grip it axially). With the 6 ga lug held between the pair of undersized divots, I then mashed the bars together in a big vise. It worked, but I later bought a proper hydraulic crimping tool at Harbor Freight to do that job. Much easier!

For what it is worth, 2 10 gauge wires in parallel (side by side, same point to same point) comes fairly close to the same current capacity as a single 6 gauge cable. 3 paralleled 12 ga is similar to the 2x 10 ga.  2 paralleled 8 ga wires is capable of more than the single 6 ga. The wire, ring terminals and crimping tools are much easier to come by for 10 gauge. And the last of the trivia, the stock battery cable in the Rhino seems to be 6 gauge.

SteveS wrote:

kris55 wrote:

The only part about this write up I understand at all is the extra ground from the engine to the frame hole the water hose clamp uses, and I think I understand the part where Chris H added an extra bat cable wire from the - post to the frame, so now he has 2 - bat cables from the - post to the frame?

Is this a correct understanding so far? If so is this sufficient enough for me to leave it at this, without trying to figure out the pigtail part? I hope so cause that one has me all sorts of lost. I am not a fan of electrical stuff at all. I'll stick to my machining instead! lol

Extra ground connections do not hurt. Very heavy wire(s) are what you want.

I'll try to explain the reason that I am advocating and the reason for cutting the wire harness pigtail away from the battery negative cable clamp and reconnecting it to the frame instead:

A common failure mode that can and will burn up the wire harness grounding wire is a failure of the ground battery cable connection at the engine case. This connection can fail from corrosion between the cable lug and engine case, or from simply becoming loose. It does happen. The problem this causes is a loss of the intended ground path of the starter motor to the battery negative terminal. The engine case is not deliberately connected to the frame and its connection to the wire harness wiring is accidental, through things like small gauge wire to sending units and the like (if any at all). Without the proper ground path to the battery negative when you crank the engine it draws a huge current and has to find an alternative path to the battery. This turns out to be through that little pigtail wire and it's grounding wire in the wire harness. It cannot handle the current and melts down. When you disconnect the pigtail from the battery the starter current cannot find an alternative path to the battery, so the wiring is saved. The problem is that the electrical system has lost its ground altogether, so we attach the pigtail to a known good grounding point on the frame. Another problem then becomes obvious, and that is the frame is not connected to the battery negative terminal, so we put a very heavy wire between the engine case ground cable connection point to the frame. The electrical pathway is now completed and all works as it should.

The reason that I advise making the heavy ground connection at the engine case rather than from battery negative terminal to frame is related to the possible failure of the battery negative cable connection to the frame and those accidental ground connections that I was mentioning. When the ground connection to the engine case and the ground connection to the frame are siamesed together, the chances are better that both ground paths fail together. Ideally, the engine simply does not crank at all until you fix the bad connection at the engine case.

I realize that this is a bit convoluted, please do comment if it is not understandable or questionable.

I think I have a better idea now.  if ther'es a pic of it after your grounding it to the frame please post it if possible. HOpefully Saturday I can get this all done and my winch put back in and have it work also, I think it just needed to be cleaned out, that's another post I have though. If I get stumped saturday I may be lighting up this thread again with more questions,lol, hopefully not though. Thanks for the help so far!!

WV Hot Rod Rhino wrote:

get a extra ground wire and run it from the motor to the frame and your good i think

That's what I did...no problems!

kris55 wrote:

I think I have a better idea now.  if ther'es a pic of it after your grounding it to the frame please post it if possible. HOpefully Saturday I can get this all done and my winch put back in and have it work also, I think it just needed to be cleaned out, that's another post I have though. :)If I get stumped saturday I may be lighting up this thread again with more questions,lol, hopefully not though. Thanks for the help so far!!

Sorry, no picture. Cut the pigtail wire off of the negative battery terminal lug right at where it comes out of the lug . Strip the insulation off of the end of that wire end and crimp on a ring terminal to fit the bolt that you intend to use to make the ground connection (1/4" for what I describe later). connect that end of the wire to the frame crossmember running side to side behind the battery. There is a Rectifier/Regulator module bolted onto that crossbar in close proximity to the battery. Remove the R/R mounting bolt closest to the battery, clean all of the contacting surfaces and apply dielectric grease, put the bolt through the ring terminal, put the bolt back in through the R/R module and tighten it up. Alternatively, you can drill and tap (perhaps M5 metric or #10-32 inch system) a new hole into that crossmember anywhere that you would like. scrape the paint off around that hole so that the ring terminal will make good electrical contact. Bolt the ring terminal down there after you have applied the dielectric grease to both mating surfaces.

REDRHINO64 wrote:

WV Hot Rod Rhino wrote:

get a extra ground wire and run it from the motor to the frame and your good i think

That's what I did...no problems!

Ahhh yes, it will seemingly work, unless or until that connection at the engine case gets loose or corroded. Then Mother nature, with the help of Zeus the Thunder god, will find her way for that current to get back to the battery negative terminal. Unless you disconnect the pigtail from the battery, that is the path that will be found and smoked.