Taking the plunge. My journey as an O/O.

I do not think any chemical tests were done. They normally take a while to process.

 

Eh, I have been o/o for nearly a year now. This is the first and only major issue with the truck. I am not yet concerned to the point where I'm worried about it.

I bought the aftermarket maintenance for a reason, and it looks like it might have been a deal. I've already provided them with my maintenance records, and they have indicated there is nothing to indicate they will refuse based on neglect.

 

No. They didn't dig deeper into it today. Hopefully tomorrow.

 

Apparently I was rushed to the front of the line because the first time they tried to fix it, they misdiagnosed. They tested the injector cups, which tested good.

After that, other jobs that had been pushed back for my truck took precedence again, and I was pushed back in line about 24 hours. Last night someone did do some more testing though, so it wasn't delayed too severely.

 

Update.

Last night they ran some pressure tests. There is a coolant leak to exhaust.

Since there is no water in the oil, it's not likely a gasket issue, so we're looking at a cracked head, according to Freightliner.

What has me very confused here is how a cracked head can lead to one-way mixing of coolant into fuel. Is there even any liquid fuel present in the head at all?

My understanding is that all the fuel passing through the injectors passes directly through the cylinders to the exhaust. Nothing that gets through an injector into a cylinder is recycled back into the fuel tanks, right? Hell, don't even answer that. I know #### well that liquid fuel is not recycled from exhaust gasses.

I am beginning to suspect that there was never any mixing of coolant into the fuel. I have never seen a diagnostic code indicating water was present in the fuel. The leak drew down about a gallon a day for about seven days of operation in a ten day timeframe. I would think that would have been enough water in the fuel to have thrown an error.

The red color in the fuel must have come from something else. I know red dye is used to indicate offroad diesel, but I wonder if someone involved in the Loves diesel supply chain might have accidentally added some red dye to on-road diesel, or dropped off-road diesel into the on-road diesel tanks. I fuel exclusively at Loves, so the fuel didn't come from anywhere else. The only fuel additive I have used in the engine is a clear antigel that I used twice in the last few weeks when I was running I-80 during a bit of a cold snap.

Another thing, but I also do not remember seeing any pink color in the fuel filter bubble. I do look at it whenever I pop the hood, and I have been popping the hood fairly regularly in the last two weeks. It might have been so faintly red that I didn't notice it. Maybe.

So. Things are both moving forward, AND seeming a bit off at the same time.

TLDR;

1) Coolant to exhaust leak identified in the head.
2) Coolant to fuel tank leak still unexplained (to me.)
3) Coolant to fuel tank leak may have never existed.
4) Coolant loss was definitely real.
5) Cracked head would have needed this degree of teardown anyway.

So far, I have no real complaints, though I am a bit confused about the coolant in fuel issue. I am going to ask if they can actually test the fuel for coolant chemicals, rather than just dye. If there is a coolant leak into the fuel tank, I'm not sure it has been found yet.

And, no, the truck does not have dedicated fuel heaters. It keeps fuel warm using the engine only.