does my cylinder wall need repair?

[hecate]

my head gasket blew up. cylinder 2 was soaked in water when I removed the heads. I also noticed piston impressions from the vertical movement onto the cylinder wall on #2. the impression is very smooth and I cannot feel the ridge with my fingernails but it still bothers me.

there was no oil consumption prior to the head failing.

do you think I can get away with putting the heads back on and not experiencing any issues for an extended period of time? I cannot remove the block as I am working in my backyard with no hoist.

can loss of lubrication on cylinder walls due to water/oil mixture cause this damage? again it is quite smooth yet worrisome as I am no expert by any means.

any input or suggestions are very much appreciated as I have paused the repairs until I gather more insight.

picture of Cylinder 2, where head gasket failed:

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[Johnny O]

When in doubt hone it out by hand. If you can feel the bore hone catching, it’s likely time for some time on the mill.

 

[hecate]

When in doubt hone it out by hand. If you can feel the bore hone catching, it’s likely time for some time on the mill.

can I get away with using a wool pad to hone it out or do I need to pull the piston out and buy those jingle drill honing adapters? I can't feel the impressions on the cylinder walls with my fingers and its relatively smooth.

also, what can cause an impression such as the one im showing in the picture. it appears like the piston has a little sway that's causing it. would it be bad bearings?

 

[LibertyTC]

How many miles on this engine? Those bores are well worn.
Could be rings. Oil & coolant do not mix well together and that cylinder wall is damaged.
Send that photo to an engine shop and ask them what they think..
If that was my engine, I may want to consider a complete rebuild.
Jasper Engines are well built with updated parts & something that you may want to explore.

 

[hecate]

How many miles on this engine? Those bores are well worn.
Could be rings. Oil & coolant do not mix well together and that cylinder wall is damaged.
Send that photo to an engine shop and ask them what they think..
If that was my engine, I may want to consider a complete rebuild.
Jasper Engines are well built with updated parts & something that you may want to explore.

thanks for the brutal honesty lol
I had just hit 120K miles before the head gasket failed. im gonna take the heads into a machine shop to have them worked on, but sorta paused everything when I saw the cylinder wall and ridges at the top of the wall.

I can feel the ridges where the rings do not reach with my fingernails but not that U shaped piston impression. its rather fine.

realistically speaking, since I don't believe I had an oil consumption issue nor did I hear piston slap, and because I am short on cash... would resurfacing the heads and replacing the head gaskets suffice for an extended period of time?

i just don't know how bad is too bad when it comes to cylinder walls. the jeep was misfiring most on this cylinder and also on 4 and 6.

 

[LibertyTC]

By chance did you do a compression test before disassembly?
I do understand short on cash, but then again interest rates are low.
It's never a good plan to do the top end and hope the bottom end is any good.
Im a firm believer in doing things correctly, the first time.
The OEM bores came with a cross hatch pattern.
Can you turn the engine to see what the other bores look like, are they smooth?

 

[hecate]

By chance did you do a compression test before disassembly?
I do understand short on cash, but then again interest rates are low.
It's never a good plan to do the top end and hope the bottom end is any good.
Im a firm believer in doing things correctly, the first time.
The OEM bores came with a cross hatch pattern.
Can you turn the engine to see what the other bores look like, are they smooth?

I had actually taken it to two mechanics for the misfiring issue 2k miles before the head blew. the first mechanic said my engine was very healthy and suspected carbon buildup as the issue, he performed a compression test and said they were fine. he did a leak down test and said there is a slight loss at cylinder 2. seafoamed it and charged me around 300.

the other mechanic said he must take the heads off to see what's going on and inspect the valves/seats. quoted me $3700 for the job.

that's when I decided to take the heads off myself. I noticed the gasket was damaged between water jacket and cyl 2. and also a slight passageway between cylinder 2 and 4.

cylinder 2 is the only one with this odd piston shape impression on the wall. cylinder 6 has a ridge, but I've read that's not too big of an issue unless I'm removing the piston. the driver bank cylinders have more caked carbon but cylinder walls look good. passenger bank is where I'm concerned, and that's the bank that was misfiring.

I do not see cross hatch patterns on any of the cylinder walls.. but maybe I'll need to clean them down more and take better pictures

I'm willing to rebuild the block if absolutely necessary and as a last resort. but as of now I'm just gathering input and trying to understand how bad this will affect performance

thank you for any additional advice

 

[turblediesel]

The ridge deposits don't look bad but that funny looking parabola is strange. Something's making that piston rock. Maybe a broken piston skirt or a sticking wrist pin. It's not ever going to seal properly.

 

[hecate]

The ridge deposits don't look bad but that funny looking parabola is strange. Something's making that piston rock. Maybe a broken piston skirt or a sticking wrist pin. It's not ever going to seal properly.

UPDATE:
i have taken the heads to the machine shop (he's been in business 40+ years), he will do a valve job and resurface/ pressure test the heads.

he says that parabola shape is not unusual and its where the water had been sitting due to the head leak. he seemed more concerned about my rod bearings and says there is a 50/50 chance ill be okay...

so now i have a few of questions...

1) right before i took he heads off, i gave the jeep one last cold start to hear for any lower engine knocking, and it sounded as smooth as butter. does that mean i should not worry too much about bearings?

2) when i drop the oil pan, can i replace the bearings without having to remove the entire block, if need be?

ive seen some youtube videos where people have changed bearings without removing the block from the vehicle.


any and all suggestions are greatly appreciated.

 

[turblediesel]

Good to know it's just a waterstained wall.

I'd leave the bearings alone. Use good oil.

 

[John P.]

IMHO If I was short on cash and absolutely needed the Jeep to run I would purchase a known good used engine and swap it. Used can be had for $800 or less then borrow or rent a cherry picker. It's real easy to get into big bucks playing the "While you're there game".

 

[GottaCRDKJ]

Just fix the head gasket and run it. Be sure to use new head bolts and follow the torque specs.
Be sure to clean the intake manifold and use new glow plugs.

 

[hecate]

I've asked a few mechanics and they all said if they were doing the repair, they'd just do the top of the engine and not worry about the bottom half.

I'll be replacing the oil pump, chains, guides, tensioners, pickup tube, pan gasket, timing sprockets, water pump, radiator, exhaust and heat bolts, egr valve, pcv valve, leaking fuel line. injectors, spark plus... pretty much everything except the balance shaft and lower engine components. $700 in parts

the machine shop will polish camshafts and do a complete valve job. he says my valve guide seals are busted. $990

im also pumping the heater core with soapy water to clean out the gunk.

hopefully all works out and then I'll have time to address the puddles of water drenching the driver side floor boards :/

ill update again once I have the heads back and put everything back together.

thank you all for your suggestions I would be lost without them.

 

[hecate]

does anyone know what the tolerance specs are for the block? I may have overdone it with the green roloc disc and want to check with a feeler gauge and straight edge? I've searched everywhere but but can't get a solid answer.

also.. yeah my hand kept slipping and there may be a scuff or two on the pistons but I didn't try cleaning them with the roloc..

 

[LibertyTC]

The Engine specs should be somewhere in the 2006 factory service manual: http://www.colorado4wheel.com/manuals/Jeep/KJ/2006-KJ-SM.pdf

 

[hecate]

The Engine specs should be somewhere in the 2006 factory service manual: http://www.colorado4wheel.com/manuals/Jeep/KJ/2006-KJ-SM.pdf

thank you. for anyone else wondering, the maximum allowed warpage is 0.1mm (0.004 in.)

 

[JeepJeepster]

Please dont say you used a roloc DISC and you used the bristle roloc... A roloc disc will ruin everything in a very quick hurry....

 

[Ksat]

$900 from the shop seems exorbitant given what you mentioned they're doing, Aside from leveling the deck, which probably isn't even necessary in your case, you can easily do the other things yourself,