The Ford Barn

oldford · 10-01-2011, 09:41 AM

I would like to remove a piston and inspect the rings. If rings are OK, can I put the piston back in, even if the rings turn a bit, and the rings will still be seated.

HP Hunter · 10-01-2011, 10:14 AM

Quote:

Originally Posted by oldford

I would like to remove a piston and inspect the rings. If rings are OK, can I put the piston back in, even if the rings turn a bit, and the rings will still be seated.

You will be fine.

Harry

Henry/Kokomo · 10-01-2011, 11:15 AM

You can remove all the pistons provided you put them back in their original cylinders. If all is well, the rings move while in use. Good luck.

Coupe35 · 10-01-2011, 12:08 PM

That's one thing I've always wonder. Do the rings, while the engine is running, rotate or move. If so, why do they tell you to put them on a piston a certain way when originally installing them.

oldford2 · 10-01-2011, 02:25 PM

I hope one of the expert engine machining guys (Ol' Ron or Walt D) chimes in here and explains the action that takes place for the rings to "seat". Do the rings/walls wear a bit? Do they move in the pistons? Always a mystery to me. I know if they don't "seat" properly you can get blow by. Thanks
John

Clem Clement · 10-01-2011, 02:55 PM

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Are you supposed to be sure the gaps don't line up? Also ring squeezers are available to compress the rings. In the junk I drive that is not a problem. I'm lucky if the piston comes up the same hole it went down in.
clem

JWL · 10-01-2011, 03:23 PM

Yes, both the rings and walls wear slighty to accomplish "seating" Yes the rings rotate on the piston. Positioning the end gaps at specified locations is good for only the first few minutes of engine operation.

ford1 · 10-01-2011, 03:27 PM

the rings dont walk around the pistons, in fact some pistons have dowls inbeded in then where the ring gap is so they cant walk, the rings wear to the cylinders because they are easier and cheaper to repair, compared to boring the block, i use hasting steel vent rings because they seem to work good in a tappered cylinder, they can expand and contract a lot in a worn cylinder with out breaking

Ronnie · 10-01-2011, 03:50 PM

Quote:

Originally Posted by ford1

the rings dont walk around the pistons, in fact some pistons have dowls inbeded in then where the ring gap is so they cant walk, the rings wear to the cylinders because they are easier and cheaper to repair, compared to boring the block, i use hasting steel vent rings because they seem to work good in a tappered cylinder, they can expand and contract a lot in a worn cylinder with out breaking

The rings do rotate in the bores while the engine is running,much has been tested to prove this.Rings that are pinned to stop rotation are referred to as pin mill rings this is very common in 2 cycle engines that have ported cyl walls.This pin is used to prevent ring rotation to keep the ring points from rotating and snagging in the bore at the port in the cly.Your post says they are pinned to prevent rotation and you also say they don't walk.Then why pin them? Snowmobiles are a common application.

R

ford1 · 10-01-2011, 04:25 PM

a lot of the english engines use the pins, basically to make sure the rings are installed with the right ring gap locations, fail safe for hand built engines and for non trained help,

oldford2 · 10-01-2011, 06:11 PM

O K
So I guess this thread is settled

Rings move

Rings don't move
Gaps line up
Gaps don't line up

And Clem still has a problem with pistons going down in one cylinder and coming up in another.
Now, how do rings "seat"?

ken ct · 10-01-2011, 06:17 PM

Quote:

Originally Posted by Clem Clement

Are you supposed to be sure the gaps don't line up? Also ring squeezers are available to compress the rings. In the junk I drive that is not a problem. I'm lucky if the piston comes up the same hole it went down in.
clem

That last statement was hilarrious Clem. still laughing on that one. ken ct.

Ronnie · 10-01-2011, 06:33 PM

Quote:

Originally Posted by oldford2

O K
So I guess this thread is settled

Rings move

Rings don't move
Gaps line up
Gaps don't line up

And Clem still has a problem with pistons going down in one cylinder and coming up in another.
Now, how do rings "seat"?

http://www.hastingsmfg.com/ServiceTi...ng_seating.htm

Walt Dupont--Me. · 10-01-2011, 06:37 PM

Cyl are honed to have a cross hatch, the new rings scrub on that cross hatch and lap them self to make a good fit in the cyl. Most of the rings on later engines have a Moly face on the top ring, that is pretty soft stuff, you have to hone the cyl with a fine stone or you'll wear that moly off before the ring get seated. Cast iron rings will seat on about anything. Chrome rings are hard to seat, you have to drive the s-it out of it to make them seat but after they do seat they last longer. Alot of guys make a big deal about lineing up the ring gap. If you just put one ring 180 degrees from the other they will be fine. I have taken more than one engine apart with the rings all lined up, I'm sure thay the were'nt put together that way. I know the 2 cycle rings are pined for a reason. Walt

36tbird · 10-01-2011, 07:10 PM

I think the rings rotate clockwise in the northern hemisphere but CCW down under. Any of our "mates" on here confirm that?

rotorwrench · 10-01-2011, 07:13 PM

Most 4 stroke engines have no pins to hold the rings, at least none that I have ever overhauled. We here in the USA don't always choose words that describe what happen visually but we are what we are. The folks in the Uk use a term called "bedding in" and it refers to the whole engine more than just one specific item. We use break in but nobody wants any thing to break in there. It all boils down to how parts that move against each other wear in a manner that provides the best possible fit for those parts.

If I was taking the time to remove a piston, I wouldn't reinstall worn rings. Now if they are near new, why waste a part that hasn't even bedded in completely yet. It's not a lot more effort to ream the ridge & hone out a bore then install some new rings but thats just my own preference. A lot depends on how much wear has taken place in the bore since the last overhaul. If the wear is minimal then a break of the glaze and some new rings will insure a decent compression. There is some method to the madness if your only doing one slug versus all eight. Ya'll can do however it pleases you if your experience is good with it.

Kerby

48-710 · 10-02-2011, 05:56 AM

36tbird,
Greetings from down under. I'm not 100% sure which way the rings rotate around the piston (LOL) but I do know that the end gaps line up after some use. In our shop we have noticed this more after an engine has banged it's self to death by detonation. That's if the land between the top and second ring is still in one piece. Subaru, WRX engines for sure, have pins in the oil rings to stop rotation because of the hole in the bore for the piston pin to be removed from the engine.

lee34 · 10-02-2011, 06:56 AM

Some engines have pins to keep rings from rotating on pistons to prevent ring end gap from being located on the bottom when not running on horizontal bore engines This was to help prevent oil that was in cylinder from getting into combustion chamber. my 2 cents lee34

Tom Morookian · 10-02-2011, 07:49 AM

My 2 cents worth,

If the ridge around the top is not reamed out you may not even get the piston out.

Whatever you do make sure the pistons 1) go back in the same hole and 2) don't rotate them 180 degrees.

10-01-2011, 09:41 AM	#1
oldford Senior Member Join Date: Jul 2010 Posts: 102	Will rings stay seated if piston removed I would like to remove a piston and inspect the rings. If rings are OK, can I put the piston back in, even if the rings turn a bit, and the rings will still be seated.

10-01-2011, 11:15 AM	#3
Henry/Kokomo Senior Member Join Date: May 2010 Location: Kokomo, Indiana Posts: 1,731	Re: Will rings stay seated if piston removed You can remove all the pistons provided you put them back in their original cylinders. If all is well, the rings move while in use. Good luck.

10-01-2011, 12:08 PM	#4
Coupe35 Senior Member Join Date: May 2010 Posts: 226	Re: Will rings stay seated if piston removed That's one thing I've always wonder. Do the rings, while the engine is running, rotate or move. If so, why do they tell you to put them on a piston a certain way when originally installing them.

10-01-2011, 02:25 PM	#5
oldford2 Senior Member Join Date: May 2010 Location: pittsfield, MA Posts: 2,086	Re: Will rings stay seated if piston removed I hope one of the expert engine machining guys (Ol' Ron or Walt D) chimes in here and explains the action that takes place for the rings to "seat". Do the rings/walls wear a bit? Do they move in the pistons? Always a mystery to me. I know if they don't "seat" properly you can get blow by. Thanks John

10-01-2011, 02:55 PM	#6
Clem Clement Senior Member Join Date: May 2010 Location: Fairfax, VA Posts: 3,393	Re: Will rings stay seated if piston removed Sponsored Links (Register now to hide all advertisements) Are you supposed to be sure the gaps don't line up? Also ring squeezers are available to compress the rings. In the junk I drive that is not a problem. I'm lucky if the piston comes up the same hole it went down in. clem Last edited by Clem Clement; 10-01-2011 at 03:05 PM.

10-01-2011, 03:23 PM	#7
JWL Member Emeritus Join Date: May 2010 Location: Fitzgerald, Georgia Posts: 2,204	Re: Will rings stay seated if piston removed Yes, both the rings and walls wear slighty to accomplish "seating" Yes the rings rotate on the piston. Positioning the end gaps at specified locations is good for only the first few minutes of engine operation.

10-01-2011, 03:27 PM	#8
ford1 Senior Member Join Date: May 2010 Location: oroville ca. Posts: 1,554	Re: Will rings stay seated if piston removed the rings dont walk around the pistons, in fact some pistons have dowls inbeded in then where the ring gap is so they cant walk, the rings wear to the cylinders because they are easier and cheaper to repair, compared to boring the block, i use hasting steel vent rings because they seem to work good in a tappered cylinder, they can expand and contract a lot in a worn cylinder with out breaking

10-01-2011, 04:25 PM	#10
ford1 Senior Member Join Date: May 2010 Location: oroville ca. Posts: 1,554	Re: Will rings stay seated if piston removed a lot of the english engines use the pins, basically to make sure the rings are installed with the right ring gap locations, fail safe for hand built engines and for non trained help,

10-01-2011, 06:11 PM	#11
oldford2 Senior Member Join Date: May 2010 Location: pittsfield, MA Posts: 2,086	Re: Will rings stay seated if piston removed O K So I guess this thread is settled Rings move Rings don't move Gaps line up Gaps don't line up And Clem still has a problem with pistons going down in one cylinder and coming up in another. Now, how do rings "seat"?

10-01-2011, 06:37 PM	#14
Walt Dupont--Me. Senior Member Join Date: May 2010 Location: Gardiner Me. Posts: 4,200	Re: Will rings stay seated if piston removed Cyl are honed to have a cross hatch, the new rings scrub on that cross hatch and lap them self to make a good fit in the cyl. Most of the rings on later engines have a Moly face on the top ring, that is pretty soft stuff, you have to hone the cyl with a fine stone or you'll wear that moly off before the ring get seated. Cast iron rings will seat on about anything. Chrome rings are hard to seat, you have to drive the s-it out of it to make them seat but after they do seat they last longer. Alot of guys make a big deal about lineing up the ring gap. If you just put one ring 180 degrees from the other they will be fine. I have taken more than one engine apart with the rings all lined up, I'm sure thay the were'nt put together that way. I know the 2 cycle rings are pined for a reason. Walt

10-01-2011, 07:10 PM	#15
36tbird Senior Member Join Date: May 2010 Location: nw SanAntonio, TX Posts: 939	Re: Will rings stay seated if piston removed I think the rings rotate clockwise in the northern hemisphere but CCW down under. Any of our "mates" on here confirm that?

10-01-2011, 07:13 PM	#16
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,465	Re: Will rings stay seated if piston removed Most 4 stroke engines have no pins to hold the rings, at least none that I have ever overhauled. We here in the USA don't always choose words that describe what happen visually but we are what we are. The folks in the Uk use a term called "bedding in" and it refers to the whole engine more than just one specific item. We use break in but nobody wants any thing to break in there. It all boils down to how parts that move against each other wear in a manner that provides the best possible fit for those parts. If I was taking the time to remove a piston, I wouldn't reinstall worn rings. Now if they are near new, why waste a part that hasn't even bedded in completely yet. It's not a lot more effort to ream the ridge & hone out a bore then install some new rings but thats just my own preference. A lot depends on how much wear has taken place in the bore since the last overhaul. If the wear is minimal then a break of the glaze and some new rings will insure a decent compression. There is some method to the madness if your only doing one slug versus all eight. Ya'll can do however it pleases you if your experience is good with it. Kerby

10-02-2011, 05:56 AM	#17
48-710 Senior Member Join Date: May 2010 Location: Mildura ,Australia Posts: 163	Re: Will rings stay seated if piston removed 36tbird, Greetings from down under. I'm not 100% sure which way the rings rotate around the piston (LOL) but I do know that the end gaps line up after some use. In our shop we have noticed this more after an engine has banged it's self to death by detonation. That's if the land between the top and second ring is still in one piece. Subaru, WRX engines for sure, have pins in the oil rings to stop rotation because of the hole in the bore for the piston pin to be removed from the engine.

10-02-2011, 06:56 AM	#18
lee34 Senior Member Join Date: Jul 2010 Location: Kentucky Posts: 127	Re: Will rings stay seated if piston removed Some engines have pins to keep rings from rotating on pistons to prevent ring end gap from being located on the bottom when not running on horizontal bore engines This was to help prevent oil that was in cylinder from getting into combustion chamber. my 2 cents lee34

10-02-2011, 07:49 AM	#19
Tom Morookian Senior Member Join Date: May 2010 Location: N. Ft. Myers, Fl. Posts: 502	Re: Will rings stay seated if piston removed My 2 cents worth, If the ridge around the top is not reamed out you may not even get the piston out. Whatever you do make sure the pistons 1) go back in the same hole and 2) don't rotate them 180 degrees.