Export thread

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

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

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.

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.

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.

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.

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.

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.

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?

PTmowerMech said:

...bearing surface is going to be worn, so I'm guessing the torgue (on reinstall) would be different, correct?

Click to expand...

No, not at all.
There is no correlation between torque and wear.

Russ2251 said:

No, not at all.
There is no correlation between torque and wear.

Click to expand...

I see what you're saying. Once two metal surfaces make contact, torquing me more, isn't going to tighten the bearing surface. Correct?

PTmowerMech said:

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?

Click to expand...

Definately not.
Overtightening the con rod bolts will distort the hole and make it oval which will pinch the crank in only 1 or 2 places wear rapidly and break in a very short time.
There is no way to compensate for wear on a direct running con rod so you toss them out & replace them if they are out of spec, the last one I bought down here was around $ 30 Aus

I'm surprised no-one has asked for PT to post his machine's info, with that, I'm sure someone could have sent him an O/H Manual which USUALLY contains all the information he seeks but may also require a separate engine Spec's sheet.

Boobala said:

I'm surprised no-one has asked for PT to post his machine's info, with that, I'm sure someone could have sent him an O/H Manual which USUALLY contains all the information he seeks but may also require a separate engine Spec's sheet.

Click to expand...

I don't have one that's actually mine. LOL.. I buy'm cheap, fix'm, use'm a little (to test them out) and sell them. If I need anything mowed, I use what I just fixed. Sort of a test drive to try and see if everything is in working order before I post it for sale.

I do have some regular customers that bring their equipment for me to work on. But it's not anything major. Anything I don't feel comfortable with fixing, I send to the shop in town. He's a guru at this stuff. In fact, Instead of buying all my parts online cheaper, I try to buy most of it from him, just for the tips and tricks he passes along to me now and then.