Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 


Reply
 
Thread Tools Display Modes
 
Old 08-21-2015, 03:50 PM   #1
Senior Member
 
coyotearms's Avatar
 
Join Date: Jan 2010
Location: Seattle, WA
Posts: 188
Electrical Short and Fire at E-350 6.0L Jumper Stud

As part of the original build SMB (Indiana) ran a cable from the + terminal of the house battery bank to the Jumper Stud that is in turn connected to the + terminal of the rearward of the two engine batteries. That Stud, the bracket that is attached to the frame that holds the stud and the battery cable from the Stud to the engine batteries is a single Ford part (# 14300B). It has been there undisturbed for five years. I never looked very closely at how SMB's wire lug is attached and now I will need to do that. Why? Last week after many weeks of very dry weather I drove the van for about 20 miles in driving rain doing errands. While I was in a T-Mobile store with the van parked outside with the motor off a short occurred at the Stud with flames shooting out from under the van. The heat apparently vaporized or dried whatever caused it, and when the fire department arrived and the smoke had cleared we saw that the flames were apparently from the red isolator that covers the stud, now on the ground all melted and distorted. There is not a whole lot of space between the frame and where the two hot wires are connected, and the area was so fried it was not possible to see the details of those connections or the cause of the short. So my only guess is that dirt collected in that small space, turned to mud and became conductive. After the mud was dried or exploded away, the short stopped. Fortunately, it was very dark and rainy so the Blue Sea battery isolator had disconnected the batteries having not sensed a sufficient voltage from the solar system or alternator. I know that its the case, because the house battery bank is protected AT the positive terminal by two fuses, one to DC Panel and Charger/Invertor and the other and the other to the Jumper Stud. Those fuses did not blow. Otherwise instead of two engine batteries shorting there would have been five! Even with only two, it was a very close call!

The fire department told me not to start the vehicle and get it towed to a garage, which I did to a local Ford dealer. They are going to replace part 14300B and I suppose it is up to me to figure out the best way to reconnect the house cable, which I am sure needs at least a new lug at its fried end (or maybe a new cable). I need help on how exactly that cable should attach to the Stud assembly. I am not even sure how that additional connection at the stud might have contributed to the problem in terms of dirt more easily accumulating there. And in the end I do not ever want to see that happen again! Maybe SMB (Fresno) does it some other way? Any suggestions would be very helpful!

So does anyone have a good idea of how to do a bullet-proof connection between both battery banks?

__________________
2008 E-350 6.0L diesel: Bought new in 2010, 4x2, 4.10 LSD, HD spring-lift all 'round,
Cruiser II Top, 6'7" inside, full-time upper bed w/ kind'a EB50 layout, cozy 4-season rig
Solar: 540 W of Kyrocera w/ Blue Sky 3024iL, 3x100 AmpHr AGM's
Electrical: 4 cf fridge, nuker, water heater, compressor
Propane: stove top, furnace Travel: https://www.lugnutlife.wordpress.com
coyotearms is offline   Reply With Quote
Old 08-21-2015, 04:29 PM   #2
Senior Member
 
larrie's Avatar
 
Join Date: Apr 2011
Location: Oregon Ciry Oregon
Posts: 2,843
Re: Electrical Short and Fire at E-350 6.0L Jumper Stud

No suggestions from me, but am very glad to hear that there was, what sounds like, only minor damage and that you did not lose the entire rig.
__________________
Larrie
Read detailed trip reports, see photos and videos on my travel blog, luinil.com.
Current van: 2002 Ford E350 extended body camper with Colorado Camper Van pop top and Agile Offroad 4WD conversion.
larrie is offline   Reply With Quote
Old 08-21-2015, 06:30 PM   #3
Site Team
 
daveb's Avatar
 
Join Date: May 2007
Location: Turlock Ca
Posts: 10,407
Garage
Re: Electrical Short and Fire at E-350 6.0L Jumper Stud

When I rebuilt my harness, I noticed that the positive terminal (going in and out) on the jump lug were against the sharp edge of the bracket and although it wasn't the cause of the meltdown I had, the cables got hot enough that the boot over the lug melted into the bracket and burned a notch into it which added to the short. And that was Ford not SMB (YMMV). What I did with new brackets (one from Blue Sea & a standard high amp jump lug) was to isolate the brackets with a 1.5" block of UHMW and countersink the studs for the bracket to it.
Yes if they had taken care with the position of the lug it would not have been as bad. I still would have had to replace that section of the harness due to the heavy amperage but if the other short (caused by Freedom Ford) had not gone to ground, it would have probably been a matter of time that I would have had issues there IMO. Not saying that dirt can't cause an issue and why I double insulate. I also worry when I do deep water crossings which is another reason I added the UHMW.
__________________
2006 Ford 6.0PSD EB-50/E-PH SMB 4X4 Rock Crawler Trailer

Sportsmobile 4X4 Adventures..........On and off road adventures
daveb is offline   Reply With Quote
Old 08-22-2015, 12:42 PM   #4
Senior Member
 
coyotearms's Avatar
 
Join Date: Jan 2010
Location: Seattle, WA
Posts: 188
Re: Electrical Short and Fire at E-350 6.0L Jumper Stud

That was very helpful, thanks! I got the van back yesterday and noticed that Ford brought the house cable to the BOTTOM of the jumper stud assembly whereas before the problem it shared the top with the engine battery able, which might not have been as good. However as seen in the photo the current routing is stretching and bending the house cable so much you can see copper near the connection lug, and it is touching an abrupt edge of a leaf spring bracket, that is definitely a problem. My short term solution is to give that cable some slack by pulling a bit more of it through the floor if possible.

That cable is 4 gauge and I have wanted to change it to 2 gauge to better size it for emergency starts anyway. So my longer term solution will use the current cable to accurately measure the length needed, get the new cable and with proper insulated lugs crimped professionally on both ends at my local marine store and then use a Blue Sea "Cable Clam" at the chassis floor that will allow the pre-lugged cable to travel through and water seal the hole.

To further bullet-proof that circuit I will also take your advice and insulate the entire bracket holding the jumper Stud with a plastic block, probably made out of Dupont Delrin. Now that I see how little the clearances are between cables and metal edges on the Stud bracket, I can see why over time something on a lug or cable could contact the bracket, or as I said previously how wet mud collecting in that area could even sneak by those Stud insulators and initiate a short.



EDIT: Looking at the picture of the cooked area and seeing how the two cables are attached at the top of the bracket, I realized that when two large cables with large lugs on their ends are connected to a threaded stud, they are forced to be at a fairly large angle relative to each other, which could force a lug to be rather close to the top edge of that bracket. Over time I can see how easy it could be for the lug to contact the bracket and short out even with shrink tubing over the lug. That might be something to check if you have such a setup on your van!
__________________
2008 E-350 6.0L diesel: Bought new in 2010, 4x2, 4.10 LSD, HD spring-lift all 'round,
Cruiser II Top, 6'7" inside, full-time upper bed w/ kind'a EB50 layout, cozy 4-season rig
Solar: 540 W of Kyrocera w/ Blue Sky 3024iL, 3x100 AmpHr AGM's
Electrical: 4 cf fridge, nuker, water heater, compressor
Propane: stove top, furnace Travel: https://www.lugnutlife.wordpress.com
coyotearms is offline   Reply With Quote
Old 09-03-2015, 07:11 PM   #5
Member
 
checksicks's Avatar
 
Join Date: Jan 2013
Location: Everson, WA
Posts: 32
Re: Electrical Short and Fire at E-350 6.0L Jumper Stud

Coyotearms,

I'm going to add a TJM IBS to link my starting batteries to the two 6-volt AGMs I am mounting on the driver side frame rail. That being said, I would like to use the positive jump stud to attach the power, which will run to a 200a relay, then to the AGMs. Do you know what Ford used to attach the cable to the jump stud? Is it a factory piece, or can I source at say NAPA? Anybody else do this themselves? I'd rather not take it to the dealership if I can do myself. Thank you.
checksicks is offline   Reply With Quote
Old 09-06-2015, 03:42 PM   #6
Senior Member
 
coyotearms's Avatar
 
Join Date: Jan 2010
Location: Seattle, WA
Posts: 188
Re: Electrical Short and Fire at E-350 6.0L Jumper Stud

What is difficult to see in the photos in my last post is that the connections to the stud are behind (inside?) of the U-bracket, where the special Ford battery cable and SMB's cable share a threaded post. The Ford lug comes off its cable at right angles to better avoid shorting on the U-bracket. The SMB lug is a standard lug in line with the cable, hence raising the chance it could short against the bracket. If you go to the Ford web site for parts you will see the cable that connects both batteries together in addition to the connection to the U-bracket. Hope that helps.
__________________
2008 E-350 6.0L diesel: Bought new in 2010, 4x2, 4.10 LSD, HD spring-lift all 'round,
Cruiser II Top, 6'7" inside, full-time upper bed w/ kind'a EB50 layout, cozy 4-season rig
Solar: 540 W of Kyrocera w/ Blue Sky 3024iL, 3x100 AmpHr AGM's
Electrical: 4 cf fridge, nuker, water heater, compressor
Propane: stove top, furnace Travel: https://www.lugnutlife.wordpress.com
coyotearms is offline   Reply With Quote
Old 09-07-2015, 08:00 AM   #7
Senior Member
 
ANZAC's Avatar
 
Join Date: May 2011
Posts: 1,005
Re: Electrical Short and Fire at E-350 6.0L Jumper Stud

Sorry, I'm missing something here, why would the house battery be connected to the jumper stud of the engine batteries? Surely the only point they come anywhere near each other is at the isolator near the alternator?
__________________
Sportsmobile-less.

"A job worth doing is worth doing at least twice."
ANZAC is offline   Reply With Quote
Old 09-07-2015, 10:48 AM   #8
Senior Member
 
coyotearms's Avatar
 
Join Date: Jan 2010
Location: Seattle, WA
Posts: 188
Re: Electrical Short and Fire at E-350 6.0L Jumper Stud

On my van that cable actually goes to a battery isolator switch that controls which battery banks get charged by solar or alternator.
__________________
2008 E-350 6.0L diesel: Bought new in 2010, 4x2, 4.10 LSD, HD spring-lift all 'round,
Cruiser II Top, 6'7" inside, full-time upper bed w/ kind'a EB50 layout, cozy 4-season rig
Solar: 540 W of Kyrocera w/ Blue Sky 3024iL, 3x100 AmpHr AGM's
Electrical: 4 cf fridge, nuker, water heater, compressor
Propane: stove top, furnace Travel: https://www.lugnutlife.wordpress.com
coyotearms is offline   Reply With Quote
Old 09-07-2015, 11:02 AM   #9
Site Team
 
daveb's Avatar
 
Join Date: May 2007
Location: Turlock Ca
Posts: 10,407
Garage
Re: Electrical Short and Fire at E-350 6.0L Jumper Stud

I'm sure it depends on the year, whether there is an isolator or separator and the model of the build. At least on mine the positive 4/0 house battery cable actually runs to a standoff stud where the inverter is located and also attaches to. From that stud SMB ran a copper jumper to the separator located a foot or so from the inverter. The solar connects to the house side of the separator. This is a typical 2006 50 model build with the standoff stud, separator and inverter under/close to the bench seat. SMB then ran another copper run to the Ford battery jumping stud on the frame. The winch power cable also came to that Ford stud. The factory battery harness is a complete unit and quite costly. I don't have a clue whether or not SMB modified the factory harness but I wasn't going to pay a thousand bucks for something I could build myself. Both starting batteries are on the passenger frame rail to the rear of the side barn doors on a 2006 diesel.
__________________
2006 Ford 6.0PSD EB-50/E-PH SMB 4X4 Rock Crawler Trailer

Sportsmobile 4X4 Adventures..........On and off road adventures
daveb is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Sportsmobile SIP or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 02:54 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.