c/diesel-mechanics

Shoutout to the old timer who told me to try a different torque sequence on a 6.7 Powerstroke head gasket

Why does nobody talk about the sheer torque loss from a single clogged injector on a 6.7 Powerstroke?

I was reading a technical bulletin from a Ford dealer in Phoenix and it stated a single faulty injector can drop peak torque by over 15% before the engine even throws a code, which explains the sluggish haul I felt on my buddy's F-250 last week.

Shoutout to the old-timer who saw me using a 3/8 drive on a stuck injector bolt

He just shook his head and said, 'Kid, that's a half-inch job, you're gonna round it off.' Has anyone else had a similar 'right tool' wake-up call?

I was torquing head bolts with a cheap beam wrench for years until a snapped stud on a 6.7 Powerstroke showed me the light.

TIL that cheap aftermarket injector for a 6.7 Powerstroke cost me $450 and a whole weekend of rework.

It failed a leakdown test after 20 miles, so I had to pull the valve cover again and eat the cost of a proper OEM part.

Question about a fuel line trick I saw at a truck stop in Flagstaff

I was helping a driver with a leak on his Freightliner Cascadia at the Petro in Flagstaff, and this old timer came over, watched for a minute, then said 'heat the flare nut with a lighter for ten seconds, not a torch'. It actually worked to break the seal without stripping the threads. Has anyone else heard of using a simple lighter for stubborn diesel fittings?

Appreciation post: I finally listened to that old-timer about using ATF for a stuck turbo vane

Had a 2012 Duramax with a completely frozen VGT actuator, and after soaking it in PB Blaster for two days with no luck, I tried the old automatic transmission fluid trick. Freed it up in about an hour and saved the customer a turbo replacement. Anyone have a different go-to for this besides ATF or PB?

A weird trick for stuck injectors on a 6.0 Powerstroke

Had a 2005 F-250 in the shop with an injector that wouldn't budge. Tried the usual puller, heat, nothing. Saw an old timer at a meet in Boise years ago mention using a 50/50 mix of ATF and acetone as a soak. Let it sit overnight. Next morning, it came out with way less force, maybe 30% of what I expected. Saved me from pulling the head. Anyone else have a go-to penetrating fluid recipe for these stubborn jobs?

Spent a full day chasing a coolant leak that was just a $5 O-ring

Had a 6.7 Powerstroke in the bay with a slow drip. Pressure test showed nothing, so I started pulling the turbo and upper coolant pipe, thinking it was a gasket. That took about four hours. Turns out the leak was from the tiny O-ring on the coolant temp sensor housing, hidden behind the alternator. The whole job, for a part that cost less than a coffee, took me eight hours from start to finish. Anyone else ever waste a day on something that simple?

Saw a really clean old Detroit Diesel 8V92 in a truck at the Boise swap meet

It was in a 1979 Peterbilt 359, and the owner had kept the original engine. The paint on the valve covers was fresh, all the lines were routed neatly, and the block was spotless. He said he does a full hot pressure wash every six months to keep the grime from building up. Anyone else run into older rigs that are still this well cared for?

Ngl, I used to think those aftermarket fuel pressure sensors were a waste of cash.

I was on a road call for a 2012 Freightliner Cascadia with a hard start near Flagstaff, and after checking everything else, I swapped in a new OEM sensor from my truck and it fired right up. The cheap one I'd put in six months ago was giving a good reading at idle but dropping out under load, which I only found by hooking up my laptop and watching the data live while my buddy cranked it. What's your go-to brand for sensors now, or do you just stick with factory parts?

My uncle told me to never trust a 'clean' used oil sample on a new-to-you engine

He said a seller could just change the oil right before the test. Bought a skid steer last month, sample came back perfect, but the coolant had traces of fuel. Turns out the head was cracked. Anyone else run into a sneaky problem like that, where one test looked good but another showed the truth?

PSA: I just wasted $120 on a 'universal' DPF sensor that didn't fit anything

Bought it online for a 2018 Freightliner, the listing swore it was compatible. Spent 3 hours trying to make it work before realizing the connector was totally wrong. Had to overnight the right part from the dealer. Anyone else get burned by these generic sensor listings?

My old foreman told me to never use a generic OBD2 scanner on a modern diesel.

He said the generic codes are useless and you need the OEM software to see the real data. I ignored him once on a 2020 Duramax and spent three hours chasing a ghost code before I plugged in the GM software and found the actual problem in five minutes. Anyone else run into this with the newer trucks?

Serious question, I was torquing head bolts wrong for years until a job in Billings.

I always did the final torque pass in one smooth pull, but the old timer I was working with there showed me his method of three short, firm pulls on the wrench. He said it lets the gasket settle and stops you from over-stretching the bolt. Now I'm wondering, is that just his personal trick or is it actually better practice? What's your method for a final torque sequence on something like a 6.7 Powerstroke?

Working on a Detroit 60 series in a Wyoming blizzard back in '98 taught me a hard lesson

We were trying to get a logging truck running in minus 20 weather and the old ether trick just would not cut it. That's when I first saw a guy use a magnetic block heater and a tarp to make a warm pocket, which got it fired right up. Anyone have other tricks for cold starts on older mechanical engines?

Had a fuel line blowout on a Detroit 60 series in the middle of nowhere, Nevada.

The high-pressure line split right at the pump fitting. I didn't have the right flare nut wrench, so I had to improvise with a crowsfoot and a lot of patience to avoid stripping it. Anyone else have a good trick for a roadside fix on those old DDEC lines?

My uncle told me to use a dab of honey on a stripped injector thread

He swore it would hold just long enough to get the new one in, and sure enough, it worked for the job on a 6.7 Powerstroke last Friday. What's the weirdest 'old timer' fix you've seen actually work?

I swore those magnetic oil drain plugs were a total gimmick until my buddy's Duramax

He put one in his 2011 LML about 18 months ago and kept telling me to check it. I finally pulled it for him last week during a service. The amount of fine metal fuzz stuck to that plug was honestly shocking, way more than I ever see on a normal plug. It wasn't just a few specks, it was a solid coating. Changed my mind completely about catching wear particles before they cycle through the whole system. Has anyone else run one long term and seen a real difference in filter life or oil analysis?

I dropped $300 on a fancy infrared thermometer and it was a total waste for my shop.

I bought one of those high-end units with a laser pointer and a digital screen, thinking it would be a game changer for finding hot spots on turbos or checking for a dragging brake. Used it maybe three times in six months. The problem is, by the time you get the thing aimed and read the number, you could have already felt the component with your hand or used a simple temp stick. It's too slow for the pace of a real shop day. The only time it came in handy was checking a customer's AC vent output, and that's not why I got it. Now it just collects dust on my top box. For the same money, I could have gotten a good set of line wrenches I actually need. Has anyone found a real, daily use for these in diesel work, or are they just a shiny toy?

Honestly, a fleet manager in Omaha told me my torque procedure was costing him money

He said I was taking way too long torquing wheel nuts on his rigs, like 20 minutes per axle. He showed me his data where just hitting spec and moving on cut downtime in half with no more callbacks for loose wheels. I switched to using a calibrated torque multiplier and now do a full set in under 8 minutes. Has anyone else had a shop boss push them to work faster on jobs you thought had to be slow?

Just remembered a bad injector job on a 6.0 Powerstroke in Flagstaff

It was a cold morning, maybe 20 degrees, and the truck wouldn't fire after I swapped the injectors. I had a bad feeling I'd pinched an o-ring on number eight. Had to pull the valve cover back off right there in the shop bay, and sure enough, the seal was torn. Ever have a simple job go sideways because of one tiny part?

Switched from a cheap scan tool to a real JPRO setup and wow

I mean, I used a basic $200 OBD2 reader for years on our fleet trucks, thinking it was fine. Then my boss got a JPRO 8 for the shop about six months ago. The difference is crazy. The cheap tool just gave me codes, but the JPRO shows live data graphs, lets me run injector cutout tests, and even has guided troubleshooting for our specific Detroit engines. Last week it pinpointed a failing turbo actuator on a Freightliner in under an hour, something the old tool would have had me guessing at for half a day. Has anyone else made a jump like that and found a specific feature that saves you the most time?

Got a stubborn injector out of a 6.0 Powerstroke by heating the housing with a map gas torch for 30 seconds first.

Always fought those things for hours, but a guy at the parts store in Tulsa said to try it and it popped right out. Anyone got a different trick for seized injectors on older Duramaxes?

I know everyone swears by the old school 1/2 inch impact for lug nuts, but after trying a newer 3/4 inch electric on a fleet of F-550s, I'm not going back.