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HELP, #6 cylinder has been wallerd out, wash down?

7058 Views 15 Replies 7 Participants Last post by  street-legal?
I just got the head off for a low compression and blow by, To my surprise it was #6, piston seems ok but the cylinder looks like its been bored out a little by the pistion, Like the rings cut the wall down. Its really smooth and no scraps.

what causes this?? clyinder wash down?
no fuel, to much fuel??? what..
I dont get it. :thud: valves seem fine, no obvise other damage.

All the others has hone marks with no visable wear at all.
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Bump.... For Help
The number 6 cylinder runs hottest of all because of how far it is from the radiator, but I don't see how that would come into play unless you have a bunch of mods. Possibly a bad injector in that cylinder would wash it down.

Ever get any "extra oil" in the crankcase? This can be a sign of a bad injector. Lot of times the fuel will end up in the oil and appear to be making oil...
cylinder wash is usually indicated by shiny cylinder walls that have their cross hatch pattern.
hay thanks guys for replying....

yes it took the cross hone off. it neatly cut the wall about .010.
The theres NO score marks or anthing like that. i havent drove it enough to see if it was making oil.. It sure it was... This is my blowby problem to i bet.

I guess ill swap that injecter when i hone and put the new piston and rings in it..
Hope fully it will work.
Are you going to have just one oversized piston?
no just one std. piston...
i cant afford to pull the block and doa full on rebuild.
Im just want to give her a cross hatch and slap her back together.
Again... This is the plan.
With a hole that's already .010 larger?

Methinks you'll be tearing the engine down again after it's all said and done....
if you have one bad cylinder, hone it out, and install a different sized piston you'll have a larger problem on your hands over time.

if you hone one, you need to hone them all to the same size, use the same sized pistons and matching rings.
Im gonna try to give it a cross hatch and slap the new one in.
if it dont work oh well i tryed hugh?

how hard is it to swap a 12v in these.
What will u hav eto do with the tranny shifting
Why not just do it right and bore/hone the entire engine correctly the first time?
Can't you install a sleeve in these motors?
Can't you install a sleeve in these motors?

not realy. . .you would ahve to remove alot of material in order to.

correct if wrong, but I do believe Cummins did make a sleeved ISB, just didnt catch on I guess.
Yes, I would ' do it rite" if i had the funds...
I just dont have anymore than a grand to spend here.
I bought a piston kit for # 6 and thats it.

i Took new reading of the wear and its not as bad as what i though.
I really thank this will work.
I thank that the top comp ring broke, started a miss fire and washed its self down from that.
The piston is fine.... It wasnt slaping or anything. just a slight miss @ idle.
When u idled it up to maybe 1000rpm the miss was gone.
I assume its been drove like this for a long time. although it only has 110,000 miles.

Ive been thanking about a 12V swap...
But would there be issues with the transmission control?
or would it work with the 12v motor?
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what good would your truck be with a 12 valve
put an isx or an n14 in it if you really need to change the entire engine out. either way swapping motors is gonna cost more money than properly rebuilding the one that is in it.

but just so you dont do it again, you definitely did overheat the number 6 cylinder.
if you do have mods, put gauges in the truck.

drop the entire body onto the 12valve frame and drivetrain thats the only way i would do it
what good would your truck be with a 12 valve

drop the entire body onto the 12valve frame and drivetrain thats the only way i would do it

I just bought the truck about 1 mo ago.
This is the suprise i got with it.

I had no idea over heating would cause this. Thanks a bunch for your help guys.
Maybe one day i can master this stuff and help u when your old and in a wheel chair! :lol3:
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