c/diesel-mechanics

I keep seeing guys skip the torque sequence on head gaskets

Last month, a shop in my town had to redo a Duramax because they just cranked the bolts down in a circle. The head warped and it leaked after 500 miles. The manual spells out the exact pattern and steps for a reason, it spreads the load evenly. How many of you still use a torque angle gauge on every job, or do you think it's overkill?

Finally tracked down that phantom oil leak on a 6.7 Powerstroke after a solid week of hunting

Turned out to be a tiny crack in the valley pan gasket that only seeped under high boost. Anyone have a trick for spotting those without pulling the turbo first?

Had a long talk with a retired fleet mechanic at the diner yesterday about 'good enough' fixes.

He was talking about this old Detroit 8V92 he used to run. Said he'd chase a tiny oil drip for hours, even when it wasn't hurting a thing. 'You stop seeing the machine and start seeing the work,' he said. That hit me because I just spent 45 minutes on a Friday night getting a coolant hose clamp PERFECT on a Duramax, when it was already sealed. Made me realize I sometimes fix things for my own head, not the truck. Anyone else catch themselves doing extra work just to feel settled?

A trucker in a Wyoming snowstorm told me to always carry two spare fuel filters, not one, and now I won't leave the shop without them.

Tried a new injector puller on a 6.7 Powerstroke and it just spun in the bore.

Used a slide hammer style tool from a buddy, but the threads on the adapter stripped right out. Learned that not all aftermarket puller kits have hardened steel threads. Anyone know a solid brand for these, or is it better to just make your own tool?

I finally got that old Detroit 8V92 running after it blew a head gasket in a Wyoming snowstorm.

We were 50 miles from the nearest shop when the coolant light came on and white smoke poured from the stack. I had to pull the heads right there in the field with a borrowed torque wrench and a new gasket set I luckily had in my box. What's the coldest or worst place you've ever had to do a major repair on the spot?

Finally got that stubborn injector out of the old Detroit 8.2 after three days of fighting it

Showerthought: That 'minor' fuel leak on a Detroit 60 series last Tuesday turned into a $3,000 injector flush after it diluted the oil for a week.

The driver kept topping it off and running it, saying it was 'just a weep', but by the time it came to us in Boise, the crankcase was half diesel and we had to pull the whole rack.

Tried a different torque sequence on a 6.7 Powerstroke head gasket

Followed the manual's pattern but got a slight leak, then a guy in Denver said to go center-out in three passes. No more leak, and it seated way better. Anyone have a go-to method for stubborn heads?

Showerthought: The difference between a cheap and a good scan tool on a 6.7 Powerstroke was like night and day.

I was chasing a weird intermittent code on a 2015 F-250 last week, and my old generic scanner just gave me a generic P-code. Borrowed a buddy's higher-end tool with Ford-specific software, and it showed me the exact sensor voltage drop and freeze frame data. How do you guys decide when it's worth the cash to upgrade your main diagnostic gear?

Changed my mind about those cheap aftermarket EGR coolers

I bought a $120 no-name EGR cooler off the internet for a 6.7 Powerstroke job last month, thinking I'd save a bundle. It failed in under 300 miles and dumped coolant into the intake, costing me a full weekend and another $450 for a Motorcraft unit to fix it right. Anyone have a go-to brand for these that won't bankrupt you but actually lasts?

Finally tried that ultrasonic injector cleaner after doubting it for years

Had a stubborn 6.7 Powerstroke injector that was just out of spec, and a buddy loaned me his Snap-on unit. The difference in the spray pattern after one cycle was night and day. Anyone have a go-to brand for these cleaners they actually trust?

I got called out for using the wrong torque spec on a 6.7 Powerstroke head gasket

About three years back, an old timer at the shop in Billings watched me torque down a set of head bolts and just said, 'Kid, you're gonna warp that deck pulling it like that.' He showed me his old service manual where the sequence was different for the updated block castings after 2015. I was using the pattern from the earlier models. Now I always double-check the exact model year and engine serial against the latest TSB before I even grab the wrench. Anyone else run into this with the newer Ford blocks?

Spent $450 on a used injector tester and it's been a total game changer

I got tired of sending injectors out for testing and waiting a week, so I picked up a used Snap-on tester from a guy in Omaha for about $450. It's an older model, but I can pop-test and check spray patterns right on the bench now. I've already used it to diagnose a bad injector on a 6.7 Powerstroke that was running rough, saved the customer a ton of downtime. Anyone else running a homebrew test setup like this, or do you all still send them out?

The time a turkey tried to move into my service bay

This was at the old farm shop I worked at outside of Spokane. I was halfway through a fuel filter change on a John Deere 4020 when I heard this weird scratching sound from the corner. Look over, and there's a full grown wild turkey just standing there, staring at me like it's waiting for an oil change. It must have wandered in through the open bay door. I tried to shoo it out with a broom, but the thing just gobbled and hopped up onto a workbench, knocking over a whole tray of 10mm sockets. Took me and two other guys about twenty minutes to herd it back outside with a piece of cardboard. Now I keep a big push broom by the door just in case. Anyone else ever had wildlife try to join the crew?

Why does nobody talk about the weird hum a 6.7 Powerstroke makes when the EGR cooler is about to go?

Had a truck in the bay yesterday from a farm outside Spokane, owner said it just felt 'off'. No codes, no smoke, but there was this low hum around 1800 RPM that sounded like a bad bearing. Spent three hours checking everything before I pulled the EGR valve and found the cooler fins were almost completely clogged with soot. The hum was exhaust gas trying to squeeze through a pinhole. Has anyone else heard that specific noise before a failure, or was this just a weird one-off?

Saw a guy at the shop trying to torque head bolts with an impact gun yesterday

He was working on a Duramax and said 'it's fine, they're all tight now'. I had to stop him and explain that you'll warp the block or snap a stud doing that, you need a proper torque wrench and the factory sequence. How many of you have seen this happen and what's the worst damage you've seen from it?

Just had a 6.7 Powerstroke fight me for three hours over a turbo sensor

Last Thursday at the shop, a 2015 F-350 came in with a limp mode code for the VGT actuator. I figured it was a quick swap, but the bolt on the up-pipe bracket was seized solid. Ended up cutting it with a Dremel after soaking it in PB Blaster for an hour. The new sensor fixed it, but man, those tight spots behind the cab are a pain. Anyone got a better trick for those rusted bracket bolts besides just cutting them out?

Appreciation post: That one week where every truck had the same weird injector knock

Last month, we had three different Freightliners in the shop with that same hollow knock at idle, all from the same fleet. One guy swears it's just a bad batch of fuel, but I'm leaning toward a sensor issue on that specific engine run. Anyone else see a weird pattern like that recently?

Had to choose between a full rebuild or just swapping the head on a 6.7 Powerstroke

Last week, a regular customer brought in his F-250 with a bad coolant leak and low compression on cylinder 3. The block was fine, but the head was warped. I had to pick between pulling the whole engine for a full in-frame rebuild or just pulling the cab to swap the head. The full job would have taken three days and cost him a lot more in labor. I went with the cab-off head swap. It took me and my apprentice a full day just to get the cab in the air, but having that wide-open space to work made the head gasket and bolt torque so much easier. We got it buttoned up in two days total, and the truck runs quiet now. Has anyone else found the cab-off method saves more time than it seems like it would on these newer rigs?

Changed my mind about using a fuel additive in older engines

I had an '88 Ford 7.3L come into my shop in Boise last month, running rough and smoking. The owner swore by a certain brand of injector cleaner, but I've always been a skeptic, thinking they were just a band-aid. To humor him, I ran a full treatment through a tank of fuel. After about 50 miles, the smoke cleared up and the idle smoothed out way more than I expected. I learned that on some of these really old units with gummed-up systems, a good cleaner can actually do a solid job before you start tearing things apart. Has anyone else had a specific additive work well on a pre-powerstroke engine?

Vent: I used to think you could just eyeball the torque on a head gasket job

Honestly, I fought with a 6.7 Powerstroke for three days last month because I kept getting a coolant leak after a head gasket swap. My old boss always said 'tight is tight' and I never used a torque wrench on the final passes. A guy at the parts counter in Billings finally asked if I'd torqued it in the right order with a calibrated wrench. I borrowed a Snap-on tech wrench, followed the factory steps exactly, and the leak stopped cold. How many of you actually follow the full torque sequence every single time?

Pro tip: I switched from a standard 3/8 drive to a 1/2 drive for head bolts and it was a game changer

Last month I was doing a head gasket on a 6.7 Powerstroke and used my regular 3/8 torque wrench for the final pass. The click felt soft and I wasn't confident. Borrowed a buddy's 1/2 inch drive Snap-on for the same job this week, and the click was solid and clear. The extra mass in the head of the bigger wrench just gives you a much better feel at higher torque values. Anyone else find the 3/8 drive gets a bit vague when you're up around 120 ft-lbs or more?

Just found out how much fuel a big rig burns at idle

I was reading a fleet maintenance report from a shop in Omaha yesterday. It said a typical Class 8 truck burns about a gallon of diesel per hour just idling. I always thought it was way less, maybe half that. That adds up to over $3,000 a year if a truck idles for 8 hours a day. I used to let my personal truck warm up for 20 minutes every morning without thinking about it. Now I'm cutting that way down. What's the shortest warm-up time you guys aim for in cold weather?

Honestly thought I'd have this 6.7 Powerstroke injector swap done in a day

Tbh, it was the stupidest thing. The new injector was seated and torqued, but it just wouldn't fire. Spent a whole afternoon checking the harness and the FICM. Ngl, I finally found the issue after like 7 hours total. The copper washer on the fuel line fitting at the rail had a tiny burr I couldn't even see, and it was letting in air. Had to pull the line back off, file it smooth, and re-seat it. Has anyone else had a no-start from something that small after a big job?