The injector thought is in my head, but so is a lifter issue that let the valve contact the piston and crack the piston. Something got the rocker to jump. My thought pattern went lifter failure, bridge jumped and it's edge caught the valve tip, longer valve travel hit the piston and it cracked. But the piston doesn't show a hard valve hit impression.

It's always hard to tell from an image compared to being there. Does the spot feel proud like aluminum transfer? I do hope it's easy cleanup, but I'm concerned as aluminum transfer should have been wiped but the rings.

 

Aluminum transfer is usually caused by overheating. The rings must be collapsed or they would have scraped off the aluminum. Sorry it wasn't just the valves.

 

Never said it was just the valves, I’m swaging it may have started with a lifter. That area of transfer is localized, it doesn’t go down the wall like a skirt failure would be. It’s about the size of the chunk missing from the piston top, which may have jammed above the ring land. Not sure the mark is just transfer.

Lifter, bridge, valve, piston, cylinder wall.

Just speculation, didn’t have a direct view.

 

I did see one of the rocker looked goofy early on. I can look at the lifters for this cylinder

 

#1 is an easy one to pull the lifter and even look at the lobe with a borescope. It looked like the rocker ball-bearing was in its correct location.




But something had to allow the loss of tension from the lifter plunger spring and if the bridge came loose, that amount of clearance. If that's the case, then either the roller came apart or the lobe wore deep. If the bridge lifted up and the edge of the bridge sat on the top of the valve stem, even with lifter/lobe damage the valve may hit the piston. The problem with that story is there are no valve marks on the piston, and for the piston to crack I would expect marks from a hard impact. And maybe a bent pushrod. It may not be what happened, but the way we would understand failures in my old world was to come up with everything, then tear each possibility down.




It almost looks like there is a line across the top of the valve stem in line with how the bridge would sit on its edge. Have you looked at the underside of the bridge for any marks?

 

I tried some muriatic acid in the cylinder and it took a little bit of the aluminum off but it was hard to get any to stay on the wall. It is looking like the cylinder wall is gouged. Bleh!

I ordered up a 101mm ball hone from Napa and that should be in on Tuesday. That will be the for sure on if I can just put a piston in it or not.

I pulled the lifters for #1 out and they looked just fine. Wondering how a guy gets the rear cylinder lifters out with the oil supply standpipe in the way. The cam lobe also looked fine but I didn't turn it over. Everything looked just fine. Also didn't notice anything in the valve bridges and no obviously bent push rods.

I found a used motor with 120k out of a 2006 on Craigslist locally here that I think I will pick up if my cylinder wall is damaged. I'll have to pull the heads off that engine and stud it, replace the STC in the HPOP, put an oil cooler in it for good measure and then probably swap my injectors in with the exception of my old #1 because I don't trust that one anymore. I wonder what I can get for an old motor? I know the front and rear covers are somewhat in demand.

What usually causes pistons to crack? The valves in the heads looked fine.

On a side note, I forgot just how dang messy it is tearing down motors! She is also pretty heavy on the one side since I only took 1 head off so far. My poor 6 liter!!!

 

It's just weird to me what happened on the valvetrain side without any fault in the system. Some of the damaged lobes I've seen are only on the nose. I've got Dexter's cam and lifters here (from the org), the lifters look fine.





My limited experience, piston fault, or excessive pressures.

 

I suppose I should turn it over then.

I'm still leaning towards too hot of a tune and maybe an injector that over-fueled. I had the SRL+ tune in with the camper hooked up. Never had a problem doing that before as long as I watched the EGTs but apparently it was right on the ragged edge.

Thanks for all your input Jack.

Whattya think about a used motor? I don't know that I want to go down the rabbit hole of rebuilding a 6 liter. Sounds like reman motors are out.

 

Just one guys opinion....

Remans from Ford are out, I'd have no problem from Ashville or KDD. In my situation, a short block Ashville (maybe long block) probably would have saved me a lot of effort had I not been so stubborn about minimizing putting more money into a rusting truck after the previous cost. ........A lot less frustrating ...... and probably more enthusiastic.

It depends on the condition of the truck, your timeframe of ownership, ....... I would not have an issue getting a salvage if I can come away feeling like it was an untouched motor with under 100k miles with good maintenance. sometimes you find that with landscape trucks if they didn't plow snow. You push 250k, we may be getting into cam/lifter issues. Dexter's cam went away with low miles due to high oil temps, bought that way from a previous owner, and like all new 6.0 owners, unaware of the oil cooler situation.

There was a local guy who was selling a freshly machined long block unassembled for $1000. I almost went to look at it but leary of not knowing how good the machining actually was. I'm definitely gun shy right now.

 

Well, it didn't hone out. I guess I'll be putting a used motor in.

 

Picked up the new engine today. It is from a 2010 e series bus. Came complete with accessories, turbo, fan and transmission for 2250.

I think I did alright

 

That's a great deal, specially on that late of a build.
How many miles on that one?
Nice thing about the e series is with them being derated they might be easier miles

 

He said about 120k give or take.

What are the different parts between the e and f series?

 

Oil filter assembly and the pan is all that I am sure on.

 

It might be the front cover too, maybe the driver's valve cover. But everything would be bolt-on from the other engine.