Well, dodged a bullet a few nights ago. One of my trucks started on fire in the shop. Dogs woke me and I was able to drag it out with minimal damage to shop but truck is gone. I’m putting Master Cutoff Switches on everything I own. It could have been disaster! Bought a few switches, and they differ as to either putting switch in positive or ground cable. What cable is best to install switch in??
Generally installed on the ground circuit (aka ground switch) My thought would be less exposed positive terminals to cause possible shorts.
In doing the ground cable, which it looks like on most of my heavy equipment, would you not have power still running directly to the starter which is then grounded where it’s bolted to the block?
But because the ground cable is disconnected by virtue of the switch, the negative side of the battery isn’t completing the circuit.
What kind of truck and any details of which component the fire started in? It might be something we should all look for.
Master switches always go on the ground side. Just went over this topic a few months ago on this very site HeavyEquipmentForums
The truck was a ‘96 Chev. 2500. Not a typical ‘96. it was very sharp, with only 83,000 miles. It had been parked in shop for 2 1/2 days prior to starting on fire. Shop is nice & clean, but we get the occasional mouse. Thinking that may have been the culprit. Who knows.
That's a shame. Glad you saved the shop.
Me too! It could have been utterly disastrous. The shop is 20,000 sq. ft. Full of equipment, classic cars, boats & such. Dogs got Ice Cream a lot the next day. The shop is 80’ from the house. I never would of heard a thing until it would’ve been to late I’m sure. As it is only dash area was burning when I got to the door. Yanked it out with a tractor that was right in front if it. Not without some injury! Everything in the shop right down to lawnmower is disconnected now. It looks like general concensus is to switch negative cable. Starting on that tomorrow.
From what I've experienced through the years a high percentage of vehicle fires that start out of the blue, the bulk head connection or power distribution box is usually in the mix if wiring has not been tampered with. PacCar [KW & Pete] both have their issues in that area. Normally start by moisture corroding/rotting connections creating resistance. Ever notice on some occasions when stripping the insulation back on a white ground wire the copper is blackened instead of shinny copper?
Truck Shop, that’s interesting as the reason we moved it into shop was a huge storm on Fri. night. Rained like crazy and the left window had been left down. The seat was wet and we were expecting more storms all weekend so we put it inside to dry out. Never thought it was that wet, but now you have me thinking.
Those are some nasty burns man!
Agree-burns can get infected real easy, be careful.
The wiring diagram from Deere for my 310 L put the switch on the + side. The boat I used to own switched +. Although your logic and reasoning for putting it on the negative side makes sense.
Many older systems before the installation of micro processors put the master switch on the positive side. There were no shut down motors and engine throttle controllers on those machines. Cat has been consistent with putting theirs on the negative side. It seems that now days all the manufacturers put it on the negative side. On the Komatsu side, there is a reason for it.
Yikes, rough burns, def need to keep those clean and covered. The top places we see electricals start is same a truck shop, the PD box and connectors, also alternator harnesses are another big one on vocational trucks it seems like. And any Paccar product, their electrical is like a ******* spaghetti mess, those things light up anywhere, engine harness, over the batts, under dash,,, especially if they have been "upfit" then you just have a ton more spaghetti.
Speaking of up-fit. Common points of electrical shorts on poorly installed snow-plow packages and lift gates. Large gauge wires poorly routed by laborers that don’t give a crap.
The Deere manual reminds that you need to give the machine ten minutes after shutdown before you turn off the power switch to allow the DEF system to purge out the lines to avoid freezing.
Same with trucks. It’s hard to get the drivers to wait long enough to purge the lines. They like to bail out of the cab as soon as they can. It’s almost not worth it to have drivers use the disconnect switches. Services like Qualcomm, Peoplenet, and Smartlogix do updates in the evening and the switches have to be on. Now, you have software issues. My neighbor just burnt down his well drilling pipe truck due to an after-hour electrical short. Could have been prevented with use of the disconnect switch. Right when I hired him to drill me a well. My luck. Been waiting all summer for well casing. Holy cow! Pipe got expensive.
Local septic guy told me his pipe went from $2 to $7 per foot. This is a supply problem article that has some interesting facts re why the shelves are bare. https://www.zerohedge.com/economics...year-global-supply-chains-increasingly-falter Joe H
Talk about thread drift. Lol. Battery switches to sewer pipe. Here is my contribution. Been waiting since April and finally was able to source 4 each, 20’ sticks of 6” API spec 5L-0026 x42 seamless Korea Hyundai. Only $600 each, delivered.
Yeah that's about why I've seen on PVC on average too, all our steel and stainless process pipe has been climbing too. Same with wire and steel stock, getting annoying having to redo bids ever few days. Even just heavy equipment parts are more all the time.
There has been a rash of shed, shop and garage fires around here the last few years, master disconnects will only get you so far. Cordless battery chargers left plugged in have been the cause of quite a few shop fires lately when the fire marshal did the investigation, same goes for extension cords left plugged in the wall when not in use [like most of us do] along with spontaneous combustion of the building itself, leaky roofs soak the rafters and the intense heat under the roof does the rest.
I’ve always had large doubts about someone determining a cause of a fire when the evidence is consumed in the fire. I’m not saying that a fire couldn’t be caused by that. I do think that when something isn’t obvious, a investigator won’t say they don’t know. They seem to jump at something that may be plausible.
We just have a couple of severe storms roll through last night, got about 6 inches in two downpours. Long story short, everything is beyond mud, so we're working around the shop and yard today, only issue is, everything I need is sitting on jobsites. So off we got with lowboy in hand to round up those machines I need, pulled into the first job site, and got ready to load. Walked down to where stuff was parked, turns out one of my machines was running, huh, wondered what was up and what the abnormal noise was, turns out the starter was on fire, and fully engaged, the engine was idling and the battery cables were literally welded to the starter, the solenoid was glowing cherry red, [didn't know that was possible for that Bakelite material], smoke was rolling out the bell housing and the starter itself had a red glow to it. The battery was literally welded to the cables on that end as well and after some jerking, swearing and hammering, we got one cable off to stop the starter. There was no ignition switch on, no key in it and now we're trying to figure out what happened. I'm thinking water got into something electrical and shorted things out. I don't think it got struck by lightening, I couldn't find any real burn marks on the machine itself, so until it all cools off, we can't take things apart to find out how bad it is. Nothing else was wrong with any of the rest of the machines, so I'll head back this afternoon to tear into it. The hour meter was hooked to the ignition switch, so when I got there all the idiot lights were on, due to the ignition switch not on, and no more hours registered than when we shut it off a few days ago. No computers and a really simple electrical system, but after looking it over, I think we get to rewire the entire machine this coming week and I haven't even taken it apart yet. I think its the closest I've ever came to anything starting on fire that actually didn't go up in flames, anyone care to guess how long a starter has to be engaged to literally light it on fire and burn the housing and solenoid and weld the cables to both the starter and battery?
Lithium ion power tool battery's spook me in regards to fire danger. I’ve had a Milwaukee 20volt get hot and run away on me. I started using a 50 cal ammo can to store mine in vs leaving them on or near a charging station. Or, on the tool, unless I’m using them. Thought is, there isn’t enough oxygen in the sealed steel can to allow sustained combustion.
It had to have shorted across the start side of ignition switch and or fried the contacts in starter solenoid.
I talked to the property owner when I went back yesterday, he and his wife left at 9:45 and they both claimed nothing was running at that time. We got there at about 10:30 or 45 minutes later and the starter was literally on fire then and still turning over. The wiring harness is a mass of melted wires, but the starter solenoid engage wire and the battery cables and all the rest are in one sheath running from the engine to the dash and go right past the battery on its way. At this point I don't think there is anyway I can determine what started what, it all needs to be replaced since its a melted mass, but I'd guess a short or a mouse got into the harness and chewed bare wires and then rain [moisture] arced across something and locked on the starter. I've had issues with a semi in the past, while driving it would lock on the starter and literally tear the starter to pieces before anyone could shut the truck down, for that issue, after 5 new starters in one year, and nobody having any ideas how to stop the problem, the last go around it lit the harness on fire, so we rewired the truck for the third time, then put two start buttons in the starter circuit, one for power, the other for ground, both have to be pushed in order to start the truck and haven't had issues since. This time on this machine, I think the ignition switch is coming out, a push button start switch is going in, and a master keyed disconnect is also going in, then the harness when replaced, will have the battery cables run in steel conduit and the starter circuit run in a separate conduit so hopefully mice won't be so able to chew on them. Anyone have any better idea's as to how to prevent an issue like this from happening again? The owner did say it was raining and lightening when they left, but we didn't find anywhere lightening would have stuck nearby and none of the rest of the machines had issues, and they were literally lined up side by side, something else that won't ever happen again either, otherwise I'd have had the potential to lose 9 machines due to fire at one time. From here on out, all machines will be left with plenty of distance between them. We've always lined them up so fueling and service the next morning was so much nicer, as of yesterday that will never happen again.
Coaldust, we've had cordless tools we were using literally catch on fire, one of my lasers running on battery power did light up and burn when in use, we had to use a fire extinguisher to put it out so it didn't catch the building on fire it sat beside, that one nobody noticed it was on fire till I lost grade on the dozer and after checking all the connections and batteries on the dozer I looked over to see my laser engulfed in flames. My lasers since have never been left with batteries in them overnight, same for cordless tools unless someone screws up and forgets. All batteries are stored so they can't rub together, I haven't gone as so far yet as to do the ammo can's, but actually that's a great idea and thank you for the suggestion.
Randy88, That’s a crazy story. Holy cow. Milwaukee Red to match my packout boxes.