Complete electrical failure, crackling, smoke!

[jbrt1989]

Sent: 7/1/2003 12:20 AM

Help!  Went out today to fire up the winnie to move it around to the driveway to begin to prepare for a small outing this weekend.

I re-hooked up the batteries, hopped in the driver's seat, turned the key and the motor made perhaps a quarter of a turn and I began to hear some popping and crackling.  Next smoke from the engine compartment.  After a brief time of panic,  visions of Ricks tragedy, and about 30 mins of wandering in, around, under, over and through the rig armed with fire extinguisher..I determined that there was no fire and that there had been some sort of short at the starting battery.  The positive cable was completely melted apart at the connector, and there was some pretty good charring right above it in the battery box.

I double checked and the batteries had all been connected properly, but, it appears that there was a break in one of the positive cable covers that might have come contact with a ground causing a super current that melted the connector. I know that break wasn't there a few weeks ago when I did an inspection for our trip back to Florida, have no idea how that got there, it doesn't appear to have melted, just somehow got cut or more specifically, looks like it got chewed up by something.  I'm checking around the box for anything that might have rubbed..

Now, my problem.... I replaced all the cables and connectors, got new batteries.. (it was getting time to get new ones anyway...)  I have absolutely no power to the starter or any thing for that matter.  No power to the genny,... nothing.  I can plug back into shore power and everything works fine, including the genny which will power the starter and fire the engine.  A meter shows the batteries all in good shape and fully charged.  Again, a couple of double checks behind myself and they are hooked up correctly.

So, my problem must be between the battery box and ... well, pretty much everything else.  I can find no burned out fuses, no cooked wires..

There doesn't appear to be an isolator between the coach and start batteries that I can see.   Could it be that Mom/dual switch?... I'm basically out of ideas.  There's got to be something I'm missing here, hoping that someone here has had a similar problem.  Obviously, something cooked that I just can't find.  The power lines from the battery box seem to splay out and head to several places.

Jeff



   
From: leftyizme   
Sent: 7/1/2003 12:32 AM

Do you see a Fusible link on any of the wires going to the starter? also check the starter relay



   
         
From: jbrt1989   

Good idea, didn't think to look there.  thanks.. and I'll keep you posted.



   
       
From: dave76Chieftain   

Dodge installed a 14 gauge fusible link at the starter relay off the "B" post on all their motorhome chassis.  That is the same post that has the large battery cable and starter cable connected to it.  That fusible link protects "ALL" of the dodge electrical system from the battery side except for the starter and starter relay post connection.



   
         
From: BoatNut   

The fact that you can fire the genny off shore-power (& not battery)and then the engine, certainly adds to the puzzle. Well here is a place where the good old multimeter comes in handy again. Be sure to inspect carefully the ground wires and their connection to chassis.

As too a fusible link causing the problem (by all means check it) I don't see how that could effect your house battery circuit, which you said is also dead. The only things common in the two battery circuits are the MOM relay and the common ground bolt, for the batteries.



   
       
From: jbrt1989   

Thanks everyone for jumping in on this one.  I know I was sure stumped.

As usual, at least with my winnie, what always appears on the surface to be complicated, usually turns out to be painfully simple.  Of course, the flip side is that anything that should be simple, turns out to be darn confusing.

Here's what happened.  There was indeed a fusible link as you said that had been popped.  I replaced that and, no problem getting power to  motor.  But, I still wasn't getting any kind of 12V coach power or genny start power.  Until I remembered that there is a switch, for some reason, right under the rear driver's side bunk, just inside that box mounted to frame of the box..  It's a basic toggle switch that I have never managed to take a real good look at and figure out exactly what it goes to.  I have no idea why I thought to monkey with this switch, but, I did, and as soon as I flipped it, the light over the bunk came on as well as a couple others that I had been flipping to check for power..

The only thing I can figure out is that I must have bumped that switch pulling things out from under that bunk when I unpacked from our Colorado trip.

It's obvious this little toggle switch is after-market.  There has been a very small dead short somewhere in the 12V coach wiring that I haven't found yet..  That's why I disconnect the batteries when it sits for any time, otherwise I'll have dead batteries 2 days later.  I guess the previous owner installed this switch that looks to be inline just before the power control box that has all the 12V and 120V breakers and fuses to disconnect the coach batteries to keep from killing them with the short.

So, everything works now.  I'm still checking everything.   I still have to figure out what chewed up that positive battery cable.  And I guess now I need to start chasing down that small coach short and get rid of that switch.  I'd like to put in some sort of battery kill switch that kills the whole rig anyway, but, I'll put the switch in a much better place than under that bunk.

Thanks again to all for the advice and help.  I didn't know there was a fusible link to the starter like that and probably would not have found it otherwise.  It was kind of hidden.  And I now believe for some reason that the genset starts off the coach system as opposed to the start battery..is that normal?

I know that the inverter coming from shore power appears to be independent of the batteries, that's why all worked on shore power...again... is that normal?  Shore power does not charge the batteries at all.  I always thought that might be normal, but, now I'm wondering.



   
         
From: leftyizme   

I'm glad you were able to solve your problem so easily, as to the wire it was probably chewed up by a hungry rodent, throw a small handful of mothballs into your compartment and they won't go near it. as to the genset cranking off the coach bat. that is normal, it prevents you from draining your starting bat., at napa we carry a switch that has a dial to switch from bat#1, to bat#2 , to both, or to off. you can mount it just about anywhere you have space. have a safe trip.--lefty



       
From: denison   

On my 1972 D22 the genset starts from the engine battery. I imagine that could be changed pretty easily though. And the shore power does not charge either of my batteries, nor does the genset. This is how it came - so I carry a small battery charger to use as needed. Have only ever used it to charge other folks batteries at a campground. denison



     
From: jbrt1989   

I think you may be right about the hungry rodent part... found some...er.. well..evidence of something leaving little surprises behind in a small compartment next to the battery box inside the coach, looks like the start of a small nest as well
I plan to fumigate tonight and hope that at least runs them off for our trip this weekend.  But, in the future,  I wanted to know what can be done to keep them out .  Baits, traps, etc.. what's the best measure?   



       
From:   

     I've heard of using moth balls to keep furry little pests away.  I was told that if I buried a few of them in my flower bed, it would keep the neighbors cat from digging in it.
                                                                         


   
       
From: denison   

Besides or instead of a good supply of mothballs, you can get a cake of camphor stuff - it has the old time medicine smell, but like mothballs is always slowly outgassing. I got it at a hardware store, it looked like hard wax, and i try to keep in a couple of my antique cars. There is also an independent feline in the neighborhood, so I cant confirm its the camphor or the feline.



   
       
From: leftyizme

Keeping pest out of anything that sits still for any length of time can be next to impossible. there are just too many places they can enter and if they can't find a hole to go through they will chew a new one. but we have used mothballs to great effect,(rats and mice can't stand them) and I use dry Boric Acid (a white powder) to repel ants under cabinets and beds. an old trick is to pour a line of lime on the ground (about 4" wide) in a circle around your entire rig, believe it or not most pests just flat refuse to cross the stuff. if you want to "permanently" remove mice there is a product called Havoc that comes in little pouches you can place anywhere and the mice eat through the pouch and in a few days "no more mouse". I lived in the country here in Alabama across from a 70 or 80 acre corn field, every year when the farmers would start to harvest the corn all the field rats and mice would come running literally for their lives out of the fields and invariably they came to our house. Each year I would put Havoc out and place a pan of water outside (one year I didn't and when the poison took effect they riddled every water pipe in my house searching for water) anyway, each year I would go out and pick up rats by the 5 gal. bucket full. I kept count a few times and had as many as 300 one week. so this stuff does work.and it is cheap too, about 1.00 for a 2-pack

[Fearless1]

Hi jbrt1989,
Can't figure out how to start a new post, so I'll use yours, it's as close as I can get, and maybe I'll get some help from someone.
A couple of weeks ago I bought a 1987 Allegro 454. Been sitting for a while, tires are dry rot. Drove it home about 45 miles. Next couple of days drove it a few times, maybe 50 miles. Last trip to town it started acting up. Made it to AutoZone. Checked battery with motor running. Clerk said it shouldn't be running, less than 1 volt. Took battery out, charged it up â€" good battery_Alternator fried. Spent the night in the parking lot. Next day install a new one when it arrived from warehouse from Advance across the street, would have to wait a week for AZ. Drove it home. Moved it a couple of times to keep it in the shade while I did some work on it. Last time tried to move it, smoke started coming out of the dash. Totally fried the Junction Block (see pix) Part no longer available, anywhere, from Red Bay to Ebay, down the Amazon, RockStone, Google and others along the way, it cannot be found. A “friend of a friend” came over and cut all the wires from the Junction Block and butt connected them together. Tried to start, only got a grunt. Dude left and hasn't returned, text that I would have to get someone else. Took battery for re-test, still good. Now when try to start, same grunt only, but a ground wire attached to housing gets hot and would melt if current was kept to it-disconnected it (see pix). It only gets hot when ignition start is engaged, not when ignition switch is just on. Still gets hot when disconnected and ignition start is engaged. If I knew which wires are attached to the ignition switch, there are six (6), I might be able to bypass the starting one. Replaced magnetic switch, called a starter solenoid by parts stores and Borg Warner. Manual calls it a magnetic switch but doesn't show or tell what wires from where attach to it. I think knowing what wire from where is attached would be good to know. Aye? The starter solenoid is on top of the starter at the bottom of the motor, very hard to get to. This switch is located on top of the motor (see pix). What could cause all those wires to get that hot? And that ground? What can I check out, and how. Won't you know it, electronics is NOT my strong suit; going shark hunting with a toothpick maybe, but not electronics. Any help, thoughts, or insights would be appreciated. Pix won't go through-too large, can email them. Thanks! Say Goodnight Gracie.

[JessEm]

In America, when the going gets too tuff, we pay someone who knows. Then we sue the guy who cut all the wires and took off.

Otherwise, I guess I would start by connecting all the wires back together the way they're supposed to be, and go from there.

[Froggy1936]

I have the complete junction box Both sides  Engine and interior along with most of the wireing  PM me  Frank

[DaveVA78Chieftain]

Original gm P/N 1114535 of the magnetic relay was superseded by GM P/N 1115616.  Used to ensure sufficient voltage is supplied to the starter solenoid mounted on the starter and initial voltage to the fuel pump for start.

We have the chassis wiring diagrams in the Members area.  For your year model, the 88 drawings (pdf page 337) are easier to understand than the 87 (pdf page 84) are.

[sasktrini]

Now when try to start, same grunt only, but a ground wire attached to housing gets hot and would melt if current was kept to it-disconnected it (see pix). It only gets hot when ignition start is engaged, not when ignition switch is just on. Still gets hot when disconnected and ignition start is engaged.

Check your grounds for engine and chassis, as well as the other end of the particular ground wire.  Seems that high resistance would cause heat.

[Fearless1]

Thanks to all for the feedback. I have checked all the grounds I could locate, disconnecting and cleaning them. However to locate the goings of that particular ground that gets hot, I would have to remove a LOT of the expanding insulation and covering from the harnesses. There should be an easier way?  i??