Engine/Transmission (1994 - 1998) Cylinder wall question

[PRattenbury]

I had the head on my engine pulled off Friday so I could replace it with a pocket ported, o-ringed head from PDR. The engine has 226,000 miles on it, which isn't too awful much for the mighty Cummins. 220,000 of the miles were in bone stock form. Since I've had the truck (the last 6,000 miles) I've never had EGT's over 1300, nor has the truck been run hot. But, looking at the cylinder walls there are vertical marks I would best refer to as scuff marks. You can't feel the scratches with a fingernail except for #5, which you can barely feel. So I ask this. Should I yank the engine out and have it freshened up, or should I go ahead with the head studs, new head, performance cam, big single turbo and big p-pump? I just don't want to put this all together, only to have to take it down again in 6 months or a year.

 

[Hammer]

Phil. .

If the scratch is that minor and the rest are as you say then I would reinstall the ehad and keep running it. I do not feel the minor marks like that are likely to lead to premature failure. So at this point then your at the crossroads of what to do and its up to your wallet which road to ride on,clean her up and reinstall the new head or pull her out and freshen her up. Personally if it was mine I would reinstall the head and kepp flogging her as we all know there are many bottom ends which have more miles on and have seen so many headgasket jobs they should have been dzus fastened on,LOL. Keep in touch and good luck... ... ..... Andy

 

[PRattenbury]

Thanks, man. That's what Signal 73 was telling me. It was running fine when I pulled it down. I was just going for more. That damn disease I have. Poweritis or something.

 

[RTillery]

If you are not having any blowby problems (any abnormal leakage or smoke or vapor) out of the vent tube, I would say you are good to go with the head. Vertical scratching is a sign of some kind of contamination going through the engine or possible overheating and a piston/ring breaking down and leaving a mark as it travels through its stroke. If it is minor, no big deal, but it is not good anyway you measure it. Make sure your air cleaner system is up to snuff. If you do have minor blowby you could still probably see good life out of the engine as long as you don't do any further damage. Keep an eye on your egt's and good luck.

 

[Vaughn MacKenzie]

I had vertical scratches on all the cylinders on my '96 when I pulled the head at 352,000 mi. Not sure what caused them but I don't think it was excessive EGT. I thought maybe carbon crusting up on the piston crown from too much light-load driving, which then broke off under high load and got jammed between the piston and wall and scratched it. Just a theory anyway.

 

[Dfuruness]

Do you have any photos of the block you can post?



Don

 

[Gary - K7GLD]

Any scratch you can feel with a fingernail should at the very least be given a light honing to smooth out - unless you're relying upon future wear to smooth it out on it's own - but I wouldn't count on it...



There's also the possibility of a broken ring causing that type of scratching...

 

[Vaughn MacKenzie]

Here are pictures of my '96's engine in this album when I pulled the head at 388,000 miles. You can see the vertical scratches along with pitting erosion caused by coolant when the first gasket deteriorated around 350,000 miles http://s113.photobucket.com/albums/n228/VMac822/My Trucks/

 

[biggy238]

Mine has the "Polishing" of the honing crosshatch on cylinder #1. My engine had 230k when the headgasket went on. Normal blowby, no excessive heat or EGT. Never even seen 1200* before.



Also, the marking is on the front and rear of the cylinder wall only, directly across from eachother. I found this odd because these aren't the "Thrust" surfaces.



The only two things that cross my mind is cylinder EGT because of the poor breathing at #1, and/or the carbon on my valves from the failing valve seals which I replaced.





On my engine, If it had just now started scuffing, The enigne will still outlast my expectations, and my use for it.



Check your lower intercooler boots for leaking. They would be a good place for your engine to pick up the sort of fine particulate to cause this.

 

[Gary - K7GLD]

Thing is, with the installation of a new ported and O-ringed head, it at least appears other power mods are planned, perhaps dual turbos or some other form of increase cylinder pressure? The added cylinder pressures, if that is the case, can cause problems with ring sealing and blowby that so far have not been an issue.



So why do half a job, when you already have a major portion of the disassembly done?



If it was me, I'd do a light overhaul, new rings and bearings, and a light cylinder honing to smooth out scuffs and scratches - then I'd sleep better at night...



But that's just me.

 

[JLEONARD]

But that's just me

Not just you... I would be inclined to agree.

Jay

 

[PRattenbury]

Yeah, I figured since the engine was pulled down as far as it was anyway, and there is damage, I'd better go ahead and get it cleaned up. Plenty of mods are planned going back together, so the right thing to do is make sure the bottom end is good to go. If the cylinders looked okay, it'd be most of the way back together by now. I appreciate everyone's help in deciding.