Ring test

PTmowerMech

PTmowerMech

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Just watching a few video's this morning and stumbled on this one, where the guy puts some Dykem Blue Steel layout die on the cylinder walls, rotates the crank, and much of the die stays on the cylinder walls afterwards.

It seems reasonable. But I'm thinking it's possible that the die that comes off while the rings are at the bottom of the cylinder, acts as sort of a lubricant to the other die on it's way it. Sort of compressing the rings a little as it travels up and down. Enough to not actually scrap most of the die off the cylinder.

Your thoughts?

https://youtu.be/5DZEkJdkMbc
 
Russ2251

Russ2251

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Silly...and does not prove anything at all.
I'd bet a years salary that a new engine would show up the same way.
 
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bertsmobile1

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People worry about apes vanishing off the face of the planet without cause as You-Tube proves that many have learned to walk upright and most post on you tube.
You use brand new rings squared off in the bore to check for roundness by holding them up to the light then repeating in several locations.
This is only done when you do not have access to proper measuring instruments. It was the std way for mechanics to do it 50 years ago when things like micrometers were only found in the research department.

And finally the air pressure behind the ring is what creates the seal, not the springness of the rings.
 
PTmowerMech

PTmowerMech

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Trying to check the ring gap, while the piston and rings are assembled and in the cylinder, seems to be impossible. Even with a flashlight. I've looked on a couple, but never could find the gap. Am I missing something.
 
cpurvis

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I always checked ring end gap while the rings were OFF the piston.

Put the rings in the bore, one at a time, then use the ring-less piston to push the ring down to where you want to check it. Pull the piston out of the bore and use a feeler gage to check ring end gap.
 
7394

7394

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cpurvis said:
I always checked ring end gap while the rings were OFF the piston.

Put the rings in the bore, one at a time, then use the ring-less piston to push the ring down to where you want to check it. Pull the piston out of the bore and use a feeler gage to check ring end gap.
Click to expand...

X 2 :thumbsup: That's the tried & true way. Using the ring-LESS piston assures the ring in the cylinder gets placed squarely at the point where you want to check ring end gap.

The u-tuber genius should have performed a 'leak-down' test prior to any dis-assembly.
 
PTmowerMech

PTmowerMech

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cpurvis said:
I always checked ring end gap while the rings were OFF the piston.

Put the rings in the bore, one at a time, then use the ring-less piston to push the ring down to where you want to check it. Pull the piston out of the bore and use a feeler gage to check ring end gap.
Click to expand...


I was watching a video of that very thing. I should've posted it. It was short, sweet and to the point. What I was hoping for, was someone who knew how to at least eyeball a ring gap with only the head off. I realize you can't get a feeler gauge in there, but if there was a way you could at least see the top ring, that would help determine if you need to go any further.

And like I said, I've looked, but couldn't see well enough.
 
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ILENGINE

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Most of the time if you can move the piston to the side far enough to see the ring gap, you have bigger issues than just checking ring gap without pulling the piston. There shouldn't be enough room between the side of the piston and the cylinder wall to move the piston far enough to see the top ring.
 
PTmowerMech

PTmowerMech

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ILENGINE said:
Most of the time if you can move the piston to the side far enough to see the ring gap, you have bigger issues than just checking ring gap without pulling the piston. There shouldn't be enough room between the side of the piston and the cylinder wall to move the piston far enough to see the top ring.
Click to expand...

Well thanks for that. I suppose if I get any deeper into this stuff, I'm gonna have to get a ring compressor. BTW, about removing the piston, obviously on a used rod, the bearing surface is going to be worn, so I'm guessing the torgue (on reinstall) would be different, correct?
 
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