Our good friends at American Diesel are hard at work despite the lockdown. In addition to keeping diesel trucks and vans on the road, they’re also building a broken-down truck into a racing machine. Back in January, we opened this saga by going into detail on the vision of the build and what the AD crew was starting with.
To recap, the truck is a 2005 Ford F-250, which naturally means there’s a 6.0-liter Power Stroke under the hood. Well, what remains of one, anyway. After 295,000 miles of driving to and from construction sites, the engine blew a head gasket; that was the end of that.
Now in the shop and with the engine removed, the guys are chomping at the bit to crack the engine open and see what drove it over the edge. We took a ride over to the shop to see what was going on. Here’s what happened.
This Thing Has Seen Better Days
The technician today was Quince, a veteran diesel mechanic who certainly knew his way around a 6.0-liter Power Stroke. The engine teardown had already had a head start a few weeks earlier, when fellow technician David removed top-end parts including the wiring harness and some of the brackets. But now, Quince was going to go all the way to the bare block.
“We’re gonna start today by removing the exhaust and heat shields,” said Quince. “We’re gonna get some of the basic stuff out of the way, but keep it organized, too.”
True to his word, Quince began by removing the exhaust tubes that routed to the turbo. With that out of the way, he removed the turbo’s heat shield. He located a support tab blocking access to the intake manifold, unbolted it, and bent it out of the way. He removed the dozen or so bolts holding the intake onto the engine and with that, the intake was free. The EGR cooler, which sat underneath the intake, was the next item to come out.
With the intake valley now bare, Quince moved onto the heads. He started on the right bank, removing the valve cover and exposing the large high pressure oil rail underneath. Before removing it completely, Quince let the residual oil seep out of the rail for a few seconds before putting it aside.
We moved onto the injectors. Here, Quince used a special tool that helped with finagling the injector connectors out of their mounts. All it took was a little rotating force and the connectors dropped right through their holes. Afterwards, Quince removed all four injectors.
The glow plug harness was next. Resting on the lower outside of the head, Quince used another clever tool to squeeze the connectors out. We were now finished with working on the head and switched back to the top end to tackle the oil pump.
Getting Into It
Similar to the high pressure oil rail, the oil pump was a leaky mess coming out. Quince held an oil pan underneath as he hoisted the pump up and out of the engine. He removed the oil filter underneath the pump as well, and threw it in the trash.
Quince moved on to the other cylinder head, repeating the steps he took on the first one. Pushrods, injectors, and more were removed, before removing the head entirely, exposing the head gasket and pistons. At last, we had a view of one of the main failure points that caused the engine to die.
“I can tell right away that this gasket had been leaking for some time,” commented Quince. “I see there are traces of where the pressure blew through the gasket. There’s also rust in the water jackets, and that tells me this thing didn’t get its cooling system taken care of. Cylinder 2 has signs of water damage.”
Despite the grim assessment, it was good to know what we were looking at. Quince moved onto the IPR valve and used a special socket to remove it. Upon removal, he looked at the screen and pointed out bits of metal filtered against the screen. “This tells me the high-pressure oil pump went south,” he said.
Quince moved onto the high pressure oil pump, dousing the seam with penetrant to help break it loose. He removed the cover plate and IPR valve, giving him access to the pump. It came out without a fuss. Quince moved back to the remaining head and removed it from the engine.
At this point, Quince cranked the engine stand so the accessory drive was facing him, and began removing components, starting with the water pump, harmonic balancer, and oil pump cover. With those out of the way, he made his way around the engine cover, removing all 17 bolts one by one. Once the hardware was gone, all it took was a little elbow grease to pry the cover off. Quince switched to the back of the engine, removing the flexplate and engine cover, and put the engine back upright as he removed the lifter guides and lifters.
By rotating the engine until it was upside down, Quince now had access to the bottom end. He removed the oil pan, exposing the inner workings including the oil pickup and separator plate.
With those out of the way, we now had a clear view of the crankshaft and connecting rods. Quince used hand tools for this step. “I don’t want to potentially hurt anything,” he explained. “I want to be able to feel if there is any damage in there.” He deftly removed the cap bolts on the connecting rods, and let the pistons carefully drop out of the cylinders.
Still Got Some Life Left In It
With the crankshaft now visible, we took the opportunity to rotate it around and get a visual on signs of wear and tear. “I can see the journals on the crankshaft and everything looks to be in order,” said Quince. “Cylinders 7 and 8 are the furthest away from the oil pump. That journal can get worn out faster than the others, but it looks good, too. That should mean the crankshaft is salvageable.”
We were nearly finished with the teardown. Quince removed the long bolts holding the bedplate to the block, and pulled it from the block. The crankshaft was now unrestricted and came out freely, albeit with two sets of hands, as it was unwieldy and covered in oil.
Quince rotated the block again to have the camshaft gear facing him. After removing the bolts behind the gear, he carefully lifted the camshaft out of the block. And just like that, the teardown was complete.
With the engine stripped down to the bone, we could relax and take a moment to look back on what we uncovered. I talked some more with Quince as well as the shop manager, Junior, to get a better grasp.
“Though we’re not going to use this block for our project truck, the good part is that it’s still salvageable,” said Junior. “We’re going to go with a block that’s been bored .20 inches over on the cylinders. But this block can still make for a good core.”
“This block shows no signs of irreparable damage,” commented Quince. “It’s not cracked or warped, at least with the naked eye. But it did suffer a fair bit of damage over the years. I noticed it suffered a seal break from the head to the block, which is a common gasket failure you see on high-mileage engines that don’t have the best service history. I also saw some pitting on the journal inserts on the crankshaft, but that’s to be expected of a work truck. The cylinder walls will need boring, but that’s about it.”
Now that we saw what spelled the demise of the F-250, we could move on to the next steps. “From here, we’ll start working on the block that we have on the shelf,” explained Junior. “We’ll wipe down the stands and send out the pistons for ceramic coating, and also get the main bearings installed. We’ll get the connecting rods stripped down and cleaned up and ready for the new pistons. Basically, we’ll do a lot of preliminary work before getting hands-on again.”
We’re eagerly anticipating when we can head back to American Diesel to see the build come back together. Helping out the build will be Alliant Power and Sinister Diesel. Stay tuned, and don’t forget to subscribe to our newsletter for the latest and greatest news, tech, features, and more.