Has this happened to anyone? (oil cooler lines)

So i was driving over this mountain pass yesterday on a forest service road and I noticed my radio started to turn on and off when it got bumpy. Thought it was a loose wire or something so i pulled over and looked under the dash. Nothing seemed loose.

I said screw it, ill figure it out later and kept going.

Then all of a sudden my brakes felt squishy. I pulled over and looked to see if i cracked a line anywhere. No fluid anywhere leaking.

But then i got a wiff of something burning.

So i turned the key off, took the key out and it took the engine 2 seconds to cut out after the key was out. Thought that was strange.

Got out and popped the hood. Right away I noticed ONE of the oil cooler lines was bubbling and smoking white smoke out of a ton of little pin holes almost like it was under pressure. The other one wasn't hot at all. I also noticed the hard lines from my brake booster reservoir were extremely hot as well and melted the plastic clip that holds the two lines together.

After it cooled off I went to turn it on again to see what it sounded like. And there was this awful clicking noise coming from the isolator switch between the two batteries. The stud on both the terminals was loose so it was actuating the switch on and off over and over again. So i tightened that back up and when to fire it up again for a second and it all seemed good besides the oil line dumping oil.

Overall I'm extremely confused. Im not sure if what happened had anything to do with that isolator going on and off while I was driving and somehow firing the glow plugs or something over and over again? (glow plug controller is gone and I use a switch in the cab)

Or if the oil cooler was clogged and it pressurized the line and melted it and it has nothing to do with the battery thing.

I ended up hiking 15 miles back into town to call a tow truck because there was no service up where I was. I finally got the truck back at our forest station and want to go through it this week.

Any help would be greatly appreciated. Im hoping its just a line i have to replace and the oil cooler. I just don't want to replace the line and cooler and it be something worse that caused it to happen in the first place.

Oil cooler as in the radiator? Did the oil cooler line fail and clog internally. I am sure the loose battery connection has nothing to do with the oil cooler or the oil cooler line. 100% positive they are NOT related. Not sure unless I was able to see it. It may have modifications to the system. Maybe a twisted oil cooler line that runs horizonal on the radiator. Hard telling what has been done or damaged. I would be concerned about oil system issues. They need corrected immediately before it is started and run again. It is possible to have the oil cooler in the radiator clogged. Report back on your findings. I am curious.

The squishy brakes and heat there sounds like brake fluid boiled. Is is still DOT 5? that has a higher failure temp then alcohol based. Are you sure it is engine oil line and not hydraulic/steering system line? That part is perplexing to me. A internally collapsed line in hydraulic system might cause overheating of that system, not that I've ever seen that. Check power steering fluid level & condition.

For engine oil line, I'd check oil level of course, then put get an oil pressure reading with a manual gauge. I'd also check engine operating temp fro good measure.

Unless one line looks much newer, recommend replacing them both while you are down there. When they are off, you could test aluminum lines and radiator chamber for obstruction with air. Not sure how anything could get in there unless oil line collapsed internally.

Agree electrical symptom is probably unrelated, also kind of curious as to what you find. Gook luck & please let us know.

Whichever fluid it is, it should be replaced ASAP
Some oils/fluids take more heat before breakdown than others, but they all have a limit.

Is the oil line that was smoking close to the exhaust or other high heat source? Thinking if so and your oil cooler is plugged, that line got overheated due to being close to the heat with no circulation.

2nd the double check engine temp idea. Is the engine temp light still working? Same question for the engine oil light?

Another possibility is that the loose battery wires was causing a very bad ground and any current was trying to go up the line. I have seen some really funky things happen with bad/loose grounds.

I have an external oil cooler on my truck the lines come from around the oil filter on the engine. Both those lines were replaced (they were leaking by where the crimp which is a common problem) 4 weeks ago by a shop since i didn't have time before I moved up to northern california for the fire season.

I wonder if it got so hot in there with the smoke that it heated the brake lines as well. I do have Dot 5 in it i just replaced the fluid a month or two ago when i cracked a brake line. I will definitely be putting new fluid in there though now.

I am going to dig into it all next week on my days off. I will let you all know what I find out.

One thing to look at is the ground strap between the engine and the firewall. Second ground at the engine to the battery, to the core support. As chevymike has said when all grounds fail then the brake lines act as a ground and get smoking hot. I have seen it happen.

I have seen oil cooler lines fail but never have seen a blockage. If the filter clogs or lines clog then the oil filter bypass recycles oil back into engine. Change oil on a regular service basis and you should never clog filter. However when someone else works on your equipment you take it on faith that they know what they are doing. There are Professional Mechanics, and then there are parts changers.

Ok..... So i finally got the parts I needed and found the issue. I have a hot wire going from the front battery to the rear of the truck to charge my batteries off the alternator. Well the wire that goes from the battery to the isolator charger had worn through and grounded out onto the battery tray.

That in turn was causing my transmission lines to heat up. oil lines to heat up and brake lines to heat up. So i am in the process of replacing all the fluids in it, change and re route the battery cable and fix oil cooler line that melted.

Just wanted to give an update. Appreciate the help that was given.

Thanks for the information.

Now would be a good time for everybody to check all areas for wires chaffing.

Any time I am into servicing a machine or vehicle I take time to check for anything that may be loose or vibrating, air cleaner wing nuts, or may need a new clamp, nylon tie. You never know.

The stock battery wiring on a CUCV is terrible, and should not be used as an example of how to do things. Running plain, unfused wire is exactly why things like this happen.

I have sheathed all of my battery hot leads in plastic loom (see below), and if I had a charging lead going to the rear of my truck it would be fused close to the battery. No way would I run a line like that and NOT have it fused and in loom.

Vehicle fires are nothing to play with. You got off easy. Very easy.

P

MarcusOReallyus said:

The stock battery wiring on a CUCV is terrible, and should not be used as an example of how to do things. Running plain, unfused wire is exactly why things like this happen.

I have sheathed all of my battery hot leads in plastic loom (see below), and if I had a charging lead going to the rear of my truck it would be fused close to the battery. No way would I run a line like that and NOT have it fused and in loom.

Vehicle fires are nothing to play with. You got off easy. Very easy.


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That’s quite the spaghetti of wiring in that pic.

Did you use regular loom or automotive loom?
The latter has a thin grey stripe running the entire length of the roll.
It is high heat and much more resilient to chafing.
Also more expensive, but well worth it.

There's a temporary power strip with two Battery Minders sitting in the background. They were hooked up because the truck was sitting for a while. In the foreground is a fuse holder I added for the glow plug wire. In stock form it is another fire waiting to happen.

I have fuse half way down that line but it is no where close to the battery. I am going to be changing that now. I definitely lucked out that I caught it in time.I found a few other places where I found some chafing as well. So i would definitely be looking over your rigs to make sure the wires are good. Pretty scary. Glad nothing too serious happened.

I tried starting my rig today after charging the batteries since they were completely drained. I believe they are shot now so going to take them in and get them tested on my next days off.

I bought boxes of the wiring loom cover from jc whitney years ago, 15,20 and still use it on all kinds of areas that chafe. I happened on some industrial stuff at work that is heavier or thicker gage that is good for hydro lines.

Not only for protection but make areas look cleaner more, engineered.

Yeah, that loom is cheap. Even the El Cheapo Harbor Fright stuff is decent.

The stock CUCV wiring has a lot of areas that should be protected.