In-Vehicle Cylinder Honing?

I need your help in making a decision on how to proceed with repair of my 4.7 stroker motor.

Background:
0. 2000 XJ 4.7L/AW4
1. I had a shop install a 4.7 ATK street stroker last fall
2. Engine ran OK, but always had a somewhat rough idle
3. Routinely (daily or at least weekly) throws a P0301 code (cyl 1 misfire)
4. Long story short, I did a dry compression test this week and found:
5. Did a wet compression test on cylinder #1 and it popped right back up to 170-175psi
6. After using a visual scope to look inside the cylinder, it appears there was some minor impact damage to the top of the piston, and some (apparently) minor scoring of the cylinder wall.

My Plan:
I am inclined to pop the head off and see if the damage to the wall is minor enough that it can be honed and re-ringed.

Question:
Anyone have experience doing this sort of honing/re-ringing work in the vehicle? Any advice or thoughts or pros/cons you can offer?

Thanks for any input!

~ Steve

I've done many in situ honing jobs - inspect the cylinder & associated parts carefully - both to source the damage, to make sure it's not going to recur, and to make sure that a hone (knocking off a couple of thousandths or so) is all you need.

If you measure it out, and find you'd need to remove a total of 0.003"-0.005", you should SERIOUSLY consider punching it +0.010" and replacing slugs & rings to match.

If you have to remove more than 0.005" in total, I would probably consider a punch & slug to be mandatory.

But, if it's light scoring and you only need to knock off 0.001-0.002" to get it done, you'll be good. Just put something over the crank journal (something impermeable!) to keep the grindings off of it, and flush it well (especially keep any crud out of the oil holes!)

It's easy enough, just keep an eye on what you're doing...

Pretty much what 5-90 said.

Read up on it. Get a cylinder hone and a inside caliper and try and keep the bore even. A reminder that you're not going to remove a ton of material, just enough to remove the scratches. When you are done, make sure to put a decent cross hatch in the bore.

If the scratches are catch finger nail deep and the pistons are scratched, you're better off to yank the block and have a machine shop clean up the bores, and replace the pistons with OS.

This would be a good time to clean up and gasket match the heads.

-Ron

Thanks guys...I kinda figured it was doable, just didn't want to get started and learn there was something I'd overlooked that made it unmanageable.

No for a follow-on question:

My block is a 4.7L, meaning it is already +0.060. I assume that means that I'm done with this block if the scratches are more than about 0.002 deep. What do you guys think?

My two bits, use a three stone hone. Not the bunch of grit balls hone as it is much easier to control.

As 5-90 has pointed out, it is remarkable easy to over hone at which point no choice is left about the repair.

Conventional wisdom says that 0.060" is the largest over bore without having to punch out and sleeve the block to get bigger.

Not sure how Titan achieved the 5.0L displacement. You could ask ScienceguyXJ as he runs one.

I might be suspicious of all 6 cylinders considering one has lost some compression.And while 130 psi not desirable considering the others are much higher ,it shouldn't be low enough to cause a misfire in my opinion. You have money into a stroker engine so the best bet is to protect your engine by pulling it and disassembling.... Just saying....

Isnt this engine still under warranty?