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Kroil piston soak odd results

fmahannah

1963 Dodge Polara Max Wedge Tribute
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As a last resort to try to free stuck oil rings before pulling my motor, I tested filling each cylinder (with heads off) with various recommended chemicals and home brews just to see if any seemed to lift out deposits when pistons were rocked back and forth.

Had best results with MMO then Kroil, with the kroil actually working best.

When I tested with Kroil though I noticed something that scared me a little. Leaving a cylinder full overnight, the next day I sucked the kroil out and saw what at first appeared to be rust in the lower half of the cylinder bore where the kroil had sat. It was a lighter brown color and not carbon. When I rubbed my finger on it it felt slightly rough and I was worried that cylinder wall was etched or rusted. However rubbing with finger loosened it and scrubbing with a little more kroil removed it. I am not sure if this was just gunk that had been lifted from rings and settled around the lower wall, or if perhaps the kroil actually lifted and removed some sort of coating that was on the cylinder walls?

Is there a coating that can be on top of the honing marks or down in them that might be dissolved by the kroil and lifted to the surface? Is this what people normally deglaze with a ball home before changing rings?

If this is a deposit or glazing on the cylinder walls then since I can't be sure kroil removed it all I will probably pull the motor anyways so I can properly bust the glaze and replace the rings, but I figured while I had the top end off I would see if anything could actually free up the oil rings.
 
As a last resort to try to free stuck oil rings before pulling my motor, I tested filling each cylinder (with heads off) with various recommended chemicals and home brews just to see if any seemed to lift out deposits when pistons were rocked back and forth.

Had best results with MMO then Kroil, with the kroil actually working best.

When I tested with Kroil though I noticed something that scared me a little. Leaving a cylinder full overnight, the next day I sucked the kroil out and saw what at first appeared to be rust in the lower half of the cylinder bore where the kroil had sat. It was a lighter brown color and not carbon. When I rubbed my finger on it it felt slightly rough and I was worried that cylinder wall was etched or rusted. However rubbing with finger loosened it and scrubbing with a little more kroil removed it. I am not sure if this was just gunk that had been lifted from rings and settled around the lower wall, or if perhaps the kroil actually lifted and removed some sort of coating that was on the cylinder walls?

Is there a coating that can be on top of the honing marks or down in them that might be dissolved by the kroil and lifted to the surface? Is this what people normally deglaze with a ball home before changing rings?

If this is a deposit or glazing on the cylinder walls then since I can't be sure kroil removed it all I will probably pull the motor anyways so I can properly bust the glaze and replace the rings, but I figured while I had the top end off I would see if anything could actually free up the oil rings.
If that motor has enough rust to freeze the rings to the walls you can just about bet it will need to be bored. How many miles are on it?
 
As a last resort to try to free stuck oil rings before pulling my motor, I tested filling each cylinder (with heads off) with various recommended chemicals and home brews just to see if any seemed to lift out deposits when pistons were rocked back and forth.

Had best results with MMO then Kroil, with the kroil actually working best.

When I tested with Kroil though I noticed something that scared me a little. Leaving a cylinder full overnight, the next day I sucked the kroil out and saw what at first appeared to be rust in the lower half of the cylinder bore where the kroil had sat. It was a lighter brown color and not carbon. When I rubbed my finger on it it felt slightly rough and I was worried that cylinder wall was etched or rusted. However rubbing with finger loosened it and scrubbing with a little more kroil removed it. I am not sure if this was just gunk that had been lifted from rings and settled around the lower wall, or if perhaps the kroil actually lifted and removed some sort of coating that was on the cylinder walls?

Is there a coating that can be on top of the honing marks or down in them that might be dissolved by the kroil and lifted to the surface? Is this what people normally deglaze with a ball home before changing rings?

If this is a deposit or glazing on the cylinder walls then since I can't be sure kroil removed it all I will probably pull the motor anyways so I can properly bust the glaze and replace the rings, but I figured while I had the top end off I would see if anything could actually free up the oil rings.
Why do you think they are stuck?
 
It is definitely not rust. The kroil is pulling something out of the cylinder walls. Here is a pic of residue and another of what color it is when wiped off. There is no rust in bores at all.

IMG_6169.JPG


IMG_6170.JPG
 
Might be loosening the carbon on the side of the piston.
How do you know the rings were ever seated? Or they had the proper grit hone for the ring type?

was it broken in correctly seat the rings?

just take it apart and start over of its burning oil.

always remove the block plugs so you don’t wash the cylinders with antifreeze when you take off the heads.

B0D8A6D7-453C-4E25-B604-A1DB16B6DFC3.jpeg
 
Last edited:
Burning oil. Engine has only 2600 miles on it but was rebuilt in 2005. Heads redone, new seals, etc so that leaves rings
Maybe, but I would doubt stuck oil ring as the problem.
 
If it was only run on synthetic oil then it's quite possible the rings would never seat.
What oil was in it?
 
Might be loosening the carbon on the side of the piston.
How do you know the rings were ever seated? Or they had the proper grit hone for the ring type?

was it broken in correctly seat the rings?

just take it apart and start over of its burning oil.

always remove the block plugs so you don’t wash the cylinders with antifreeze when you take off the heads.

View attachment 1329401
Ok I agree it is likely antifreeze coating reacting with the kroil. Not all cylinders are doing it so that makes sense. Yes I know not draining the block was a brain fart on my part LOL.

Yes it was broken in correctly by the shop that built the engine. Had been run very rich for some time before I bought the car. Smoke started after I corrected the carb issues.

Thanks
 
If it had been running rich for a while after the rebuild, the extra gas could have ruined the rings or cylinders
 
If it had been running rich for a while after the rebuild, the extra gas could have ruined the rings or cylinders
Yet the Kroil sits on top of the piston.

Just seems like there could be something else going on and more to the story.
 
Yet the Kroil sits on top of the piston.

Just seems like there could be something else going on and more to the story.
All wet and dry compression tests passed quite nicely, if it is rings it is not compression rings. Valve quides were in spec according to machine shop, so had them machine for positive seals on exhaust, already had them on intakes. They also did a valve job and took off .008
It is also not PCV system. When I pulled heads the last time there was oil in #8 exhaust port on back side of closed valve.
 
Wow, there is alot going on here. The Kroil might be corrosive and that is oxidation that you are wiping off the cylinders.
How much oil is this engine burning?
It sounds like everything has been rebuilt recently, so it is most likely the rings not sealing correctly.
What kind of rings are they? Some of the higher end stuff is more sensitive to proper break in and cylinder prep etc...
Maybe one or two of the cylinders is not sealing as good as the ones that you tested. I would do a leak down test to pinpoint which cylinder or cylinders is leaking. Just my opinion.
 
Leakdown test also passed. Forgot to mention that. I tested all cylinders for compression and leakdown. The puzzler here is that when I got the car it was not smoking out the exhaust (other than running rich), but once I got two good carter carbs on it I get blue tinted smoke as soon as engine warms up and it is constant.
 
It is definitely not rust. The kroil is pulling something out of the cylinder walls. Here is a pic of residue and another of what color it is when wiped off. There is no rust in bores at all.

View attachment 1329388

View attachment 1329389
It is definitely not rust. The kroil is pulling something out of the cylinder walls. Here is a pic of residue and another of what color it is when wiped off. There is no rust in bores at all.

View attachment 1329388

View attachment 1329389
Why is nobody thinking that the krill itself is depositing a residue on the cylinder wall, given the red color of kroil? Rust would not be shiny like that.
 
Leakdown test also passed. Forgot to mention that. I tested all cylinders for compression and leakdown. The puzzler here is that when I got the car it was not smoking out the exhaust (other than running rich), but once I got two good carter carbs on it I get blue tinted smoke as soon as engine warms up and it is constant.
Did you change or remove the intake maniflod during the process?
 
Did you change or remove the intake maniflod during the process?
Not until after the exxhaust smoke started. Some said intake gasket leak, others seals so I replaced both and it made no difference
 
Chances are it needs honed & new rings, running rich will wash the cylinder wall of the oil & cause the rings to wear very fast
 
so had them machine for positive seals on exhaust, already had them on intakes.
What type of positive seals? My first set were teflon and they were ****. Loads of blue smoke on start ups and smoke when full throttle, and I thought it was bad rings. Changed to viton seals, all problems gone.
 
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