1988 Bigfoot B19 - Purchase gone wrong - electrical issue

[Marcfrqc]

Hello everyone, Rv newbie here,

Having research Rv's, truck camper and off road trailer to the bitter end and having come to the conclusion that I have to haul my wife, kid and husky with me, I figure we would go no where with a rooftop tent or truck bed set up... so I decided on buying a fiberglass Rv to avoid most RV problems..... well let me tell you about my buying experience.

So I had only gone to look at a 1975 thrillium rebuilt before and stumbled on this bigfoot add and was lucky enough that the previous buyer didn't buy it site unseen so I thought.

I went to look at it, everything was going good and everythig worked then we hear his wife yelling smoke is coming out the top. Ran around figure its coming from the fridge vent scramble a screw driver and open it the 120 volt plug is smoking and melting... but the rv is not plugged in to shore power only battery and truck power... unplug it smoke settle and thankfully no fire. The cable was partly melted all the way to the fridge... the owner now scrambling to figure out the cause check the rear running light he rewire last night, no link to that. Meanwhile I just continue with my buying check list I printed from this site. Then we try the fridge on propane and 12 volt and it appears to still work on those. I get the price down a bit and buy it anyway.

I leave the place before finalizing my insurance as they were taking forever wanting photos due to the age of the unit. Testing the brake with my controller on the way out. 2 kms in I pulled over to make sure nothing else caught on fire.... well the 7 pin plug in the truck is smoking... I pull it and one pin melted(later found to be the ground plug). On top of that someone pulls over and tell me something fell off the roof which looked like a roll of tape... so I m like did I lose a roof cover or something important???? Ha I text the owner to let him know what happenned not knowing if he'll ever reply... I drive back to look for whatever fell off no luck. I pull over ear the owner's place having decided to wait for full insurance coverage before driving further.

Owner's text's back and come right to my location to help me trouble shoot things. We follow the battery wire and turns out the wire is wedged under the propane tank stand between that and the frame and frayed. It does look like it was there for an extended period of time. Ex-Owner offers to fix that wire and give me some money back... i accept the money back, but by then I'm decided to have a professional fix it and assess the electrical system. Thankfully I had emergency red strobe light with magnet I put on the rear bumper to two it without lights. Towed it back home and simmered thinking about it all looking at every corner of thd internet to see if power to the frame will make its way back to the fridge 120 volt ground wire. Nothing found on the subject, but only plausible solution. Also answer why the plus would melt to my truck with too much power going back to the truck (these are only theories as I have yet to fix it). Ex-Owner also agrees this would make sense.

Now am I crazy to have bought this in the first place while it almost caught on fire during the buy???? Hahahah

And does the problem which occured makes sense???

Anyway thanks for the add!!!!

[lisantica]

Wow, that's a wild story! I may have ran from that purchase, but I do see the silver lining in it.

The good news is you know it has issues up front. I think it's better that you now get to address them and not have that dangerous surprise while you were out with your family.

Looking forward to other replies to this thread.

Once you get it looked over and back to proper functioning, I wish you many safe miles with your Bigfoot.

[ZachO]

Dang. Sounds like the seller was very understanding. Hopefully that was all just crazy timing. I’ll bet they felt really bad.

My worst nightmare (relative, obviously), is selling someone a vehicle and having it break down on them on the way home. That happened to me once. Terrible feeling.

[Chet_B]

Hi Marc

“And does the problem which occured makes sense???”

Yes. Here is a possible answer; the shorted wire under the propane tank is probably the +12 volt charge line from the tow vehicle.

The initial fire was caused by the onboard RV +12v battery sending current through the RV wiring to the shorted wire under the tank. This current lasted until an overheated wire melted open thus ending the current flow and stopped the smoking fire.

The overheated trailer plug was caused by the tow vehicle supplying a +12 volt charging current into the shorted wire. The reason the ground connection (-12 volt path) overheated is that it was a higher resistance connection than the +12 volt pin. The most heat occurs at the weakest point in the wiring.

The fix is to replace or tape the shorted wire. Find the melted wire in the area where the smoke was coming from. Replace all burnt or melted wires. Check at the RV battery for an overheated/melted insulation on the small +12 volt charge line.

Replace the tow vehicle trailer connector. Inspect the +12 volt charge line from the trailer connector forward to under the vehicle hood for possible overheated/melted insulation. Inspect and/or replace the ground wire.

Have a good day,
Chet

[Marcfrqc]

Originally Posted by Chet_B

Hi Marc

“And does the problem which occured makes sense???”

Yes. Here is a possible answer; the shorted wire under the propane tank is probably the +12 volt charge line from the tow vehicle.

The initial fire was caused by the onboard RV +12v battery sending current through the RV wiring to the shorted wire under the tank. This current lasted until an overheated wire melted open thus ending the current flow and stopped the smoking fire.

The overheated trailer plug was caused by the tow vehicle supplying a +12 volt charging current into the shorted wire. The reason the ground connection (-12 volt path) overheated is that it was a higher resistance connection than the +12 volt pin. The most heat occurs at the weakest point in the wiring.

The fix is to replace or tape the shorted wire. Find the melted wire in the area where the smoke was coming from. Replace all burnt or melted wires. Check at the RV battery for an overheated/melted insulation on the small +12 volt charge line.

Replace the tow vehicle trailer connector. Inspect the +12 volt charge line from the trailer connector forward to under the vehicle hood for possible overheated/melted insulation. Inspect and/or replace the ground wire.

Have a good day,
Chet

Thanks Chet,

Really appreciate the input. I think I removed the plug quickly enough the save the truck plug had to scrape some plastic off the metal pin, but tester says all ok there. I will check wire to the front, but its all in factory harnesses. The melted wire is visible in the fridge outside openning as it is its 120 volt regular plug in. That will stay unpluged. Doubt I can re-wire it as it melted to the fridge so no 120 volt fridge for now. And changing the wire and plug in 7 pin connector today and will test things out. I think the 12 volt system is fine as the fuse went on that. Thinking to put a fuse right at the battery to prevent that, instead of inside the rv.. but its probably one in a lifetime...

Marc

[Marcfrqc]

Also in regards to finding the ground wire. The only thing to that I can find on the frame is a green wire tht goes inside the bixed frame... kinda close to tbe brakes..

[ZachO]

I'll check, but I think I remember my ground wire being on the driver side, in front of the axle.

[Marcfrqc]

Thanks Zach,

I confirmed this is the ground wire, it was just covered with an inch of caulking... all good there also tracked the wires as much as I could no indication of melting inside the coach just that 120 volt plug on the outside compartment of the fridge.

Again thanks Chet, as I tracked my truck plug and it melted the harness connection away from the plug itself... will have to get that fixed...

The 12 volt is back working, though left it unplugged for now as I dont quite trust it.

Marc

[Julie T.]

What a story! I'm always impressed with the collective knowledge in this group! Good luck with your repairs!

Julie

[Marcfrqc]

Julie it is a 1988.

Well after Toyota wanted 500 bucks for the truck trailer plug and another 175 for the harness connection, I had asked how much it would be to replace the harness to the front and that would be 3 grand.... insanity and thievery. My local shop said they could rewire everything for 300 bucks...

I went with changing the plus and harness connection myself so saved a ton. And the engine compartment connection had no signs of heat.

Everything seems to work took the trailer to r inspected for the road as a required every two years in Nova Scotia hopefully no surprise there.

I'd still like to have an electrician or rv technician check the 120 volt system, but I have a trip planned where we are going to boondock so no worrying about that for now.

[ZachO]

That’s great to hear. Sounds like that wire finally causing issues was just terrible timing for the seller, perfect timing for you ($-wise), and it’s going to be a good trailer.

I am jealous. I love my trailer and it’s what works best for me currently, but the Bigfoot 19 and 5th wheel are both serious upgrades if you’ve got the truck to pull them.

[Marcfrqc]

Yeah hopefully you are right, I definately bought a dual smoke alarm with photoelectric and ionization system to be safe hahaha

[Alex Adams]

Just unplug the trailer every night before bed. You'll be fine!

[Marcfrqc]

Here some photos of the trailer!

[ZachO]

Outside looks great.

If it was mine, step one would be replacing those 4" drop axles with straight axles and getting that thing up off the ground.

[David Tilston]

Just before I became a Trillium fanatic, I was days from pulling the trigger on a 19' Bigfoot. I still have a soft spot in my heart for them. I love the floor plan. The Trillium 5500 would have been a better trailer if it had the same plan.
Do you have any interior pictures? The one I almost bought had a dark wood interior. I have seen a variety of interior finishes.

[Marcfrqc]

Originally Posted by ZachO

Outside looks great.

If it was mine, step one would be replacing those 4" drop axles with straight axles and getting that thing up off the ground.

I am thinking to do an axle flip, what do uou mean by straight axle?

I ll snap a few pics of the interior when I get a chance, we gonna do some upgrade over time inside probably next year though.

[Marcfrqc]

See attached interior photos.

[ZachO]

Looks great. It takes up a lot of counter space, but I do love that sink.

Not sure how much you already know so here goes - what most people call an axle flip is not an axle flip. It’s actually moving the leaf springs from under the axle to on top of the axle, giving you a couple inches lift. This raises the body of the trailer, so gives you more clearance for the fiberglass, but the axle is no higher, so total ground clearance hasn’t changed. Basically, this is a “body lift” if you ever got into such things. There are legitimate reasons to do them but often they’re just cosmetic. So an axle flip aka body lift would allow bigger tires, and get the fiberglass tub a bit higher so you don’t drag at big dips in the road.

What more of us do with this type trailer is put in a straight axle. If you crawl under there, you’ll see that right before the axle attaches to the back of the wheel, it drops, about 4”. You can replace the entire axle and get new brakes and everything (not a bad idea), but replace it with a straight axle. No 4” drop, so you raise everything 4”.

I know people make it work, but I’m always shocked at how low these things ride. Around here, I’d be scraping bottom every time I went from a parking lot to the street.

Depending on the condition of your axle/bearings/brakes you may decide it’s good as-is and that works. But if all those components are old and you think it sits too low, a new, straight axle is worth looking into. Well, I guess two of them in your case.

Only other advice is DO NOT have this type work done at an RV shop. Bring it to a trailer shop. Price difference is staggering.

[Marcfrqc]

Thanks a lot Zach,

Yeah definitely something to consider, at first sight everything looks good underneath aside from some surface rust. The idea is that I would do the "axle flip" myself aside from getting the new bracket welded on, so basically almost no cost. I hadn't considered the straight axle until you mentionned it, makes a lot of sense since then you have the full clearance of the tire/rim up to the axle. If I bought all new I could also do it myself. I was trying to find some tread on it on this site without success.

Marc