polishing piston rings?

[hoodeng]

As has been pointed out, a lot has changed since David recommended finishing the ring working edges. As his books remain write time relevant but print time stationary, and can not amend themselves as time goes by,,, does he need to apologize or admit wrong due to progress? No. It was relevant at that time.

I can remember rings offered in the past that needed a particular run in procedure to give good service, one was the chrome faced rings, they had to be hammered from start up to seat properly, if the initial driving was pussied they would polish the bore and have leak down issues. Others were straight soft cast iron, very easy to bed in, after extended use would loose tension and seal, they still gave acceptable service. Modern engines very rarely need hone and re ringing and if they do it is usually due to incorrect usage or treatment. A Napier second ring has an acute hook that does not damage the bore but gives a new level to oil control, the older reverse torsional twist also give great service, interesting is that a reverse torsional twist when installed upside down is a pumper, clearly indicating its effect.

Would i use new old stock? no thanks, i would go with the latest iteration of any part [and machine process] in an engine where possible. With what i do it is not unusual for a customer with a historic engine to have a hoard of old black and orange box's just waiting to see the light of day, these box's have been opened and handled more times than they have had christmas dinners. Finger prints etched in time, and they still want to use this stuff even when the damage to the parts has been identified.

Cheers.

[Fusion Works]

Wonder if any benefit could be had from REM finishing rings? Probably just damage the rings during the process though.

[englertracing]

David posted about welding a conn rod.....
he wanted to flip a piston to get the pin boss above deck with a window through the piston crown, this setup would make it to easily install rings and use an electric motor to turn the getup.. all to polish/prebreakin the rings

[mag2555]

The oil rail rings are the hardest of all the rings since there steel. and as such the most likely to put combustion leaking scratches into the cylinder walls.

None the less I spend the needed time get these Nicely rounded over also reguardless of how thin they are, so don’t talk to me about how hard it is to do work on thin top and second compression rings!

[Belgian1979]

As has been pointed out, a lot has changed since David recommended finishing the ring working edges. As his books remain write time relevant but print time stationary, and can not amend themselves as time goes by,,, does he need to apologize or admit wrong due to progress? No. It was relevant at that time.

I can remember rings offered in the past that needed a particular run in procedure to give good service, one was the chrome faced rings, they had to be hammered from start up to seat properly, if the initial driving was pussied they would polish the bore and have leak down issues. Others were straight soft cast iron, very easy to bed in, after extended use would loose tension and seal, they still gave acceptable service. Modern engines very rarely need hone and re ringing and if they do it is usually due to incorrect usage or treatment. A Napier second ring has an acute hook that does not damage the bore but gives a new level to oil control, the older reverse torsional twist also give great service, interesting is that a reverse torsional twist when installed upside down is a pumper, clearly indicating its effect.

Would i use new old stock? no thanks, i would go with the latest iteration of any part [and machine process] in an engine where possible. With what i do it is not unusual for a customer with a historic engine to have a hoard of old black and orange box's just waiting to see the light of day, these box's have been opened and handled more times than they have had christmas dinners. Finger prints etched in time, and they still want to use this stuff even when the damage to the parts has been identified.

Cheers.

https://www.thriftbooks.com/w/how-to-bu ... q=14306639

Still for sale BTW.

Sadly the guy himself never seems to explain what he writes on forums like these.

[engineguyBill]

It would be interesting if you would call the ring manufacturer and see what they suggest.

The ring manufacturers will respond, that filing and/or polishing the piston rings is not necessary and will not enhance the functionality of the rings at all. My recommendation is to inspect the rings completely with a magnifying glass and if any questionable areas are encountered, then inspect further with your microscope. Ring surfaces with any pits or surface imperfections should be returned to the ring manufacturer.

[hoodeng]

'Perfect Circle' accreditation Bill? benchmark company with benchmark training. Had to be good for Mahle to want them.

Thing is these days a number of guys don't check ring gaps or even wash a set of rings much less micro examine them,,, out of the packet, look for dots and on they go, some don't even look for the design to match fitment dots, much less understand what the design differences even are. I suppose for a number it does not matter.

Mag, oil ring rails should be barrel faced already, correct me Bill, but i think the original design of three piece oil rings by Mahle was called 'SU50' ?
Detroit two stroke series engines had chrome plated steel rings, these rings could be hammered out straight, then twisted into a pigtail, a ring bent on one end and the other end sharpened into a scriber, now, that's a tough ring.

I can tell a story of an engine having BonAmi poured down the plug holes and cranked in most unusual ways. But it's a bit long.

Cheers.

[BLSTIC]

I can tell a story of an engine having BonAmi poured down the plug holes and cranked in most unusual ways. But it's a bit long.

Cheers.

Is that the one where underworked Cleveland engines had "deglazing powder" poured through a running engine?

Do tell if it's similar to that, that sentence is all I know of the story

[hoodeng]

BLSTIC, funny you should mention Cleveland.... Back in the seventies i worked for the railways, we had a sizeable fleet of Case W7 and W9 loaders that suffered from glazed bores on occasions, the cause of the glazing was operators cranking the engine up first thing in the morning and turning off at the end of the day, these things would idle for hours on end,,the reason? operators thought the bosses were looking at the hour meters to see if they had been on the job.
Anyway, Case sold cans of BonAmi with their label over the top as de-glazing powder, the procedure was to get the engine to temp, max rpm, load the engine as much as possible by crowding all hydraulics, then sprinkle the powder down the inlet, the engine with a little time would clear up in the exhaust. On subsequent overhauls these engines did not display much other than matte bores.
Here we go.
Guy comes into pub all upset and wanting to kill the guy that told the story of Case de-glazing powder,,,story goes, he had a smokey Cleveland and was selling it, remembers story,[partly] pours BonAmi down plug holes re installs plugs etc and goes to fire it, motor locks straight away, two battery's then three battery's, another starter, no turn. long bar on balancer nut with lever chain block attached to telegraph pole, car leans more than turns,,next step, tow start, gets mate to tow Falcon with old Benz, up to speed and drops clutch in Falcon,,locks up straight away and puts guy driving Benz into windscreen,,,both now visit pub and tell story, i'm sitting there with a number of other regulars, a couple of guys that know the story are looking at me but keep their mouths shut....After a while of peace it is suggested that the heads should come off and check out what is going on, heads off and bricks of BonAmi discovered in cylinders. It was quite a while before we discussed the full story.

Be careful when giving advice, you have no control over how it will be applied.

Cheers.

[67satellite]

My father, who went into the automotive repair business shortly after W.W.2,said Bon-Ami could be used if the rings in a rebuilt engine failed to seat. He said it would be mixed with kerosene and trickled down the intake. Never mentioned pouring it into the plug holes.

[MadBill]

With Bon Ami's motto being: "Never scratched yet" how could you go wrong?

[engineguyBill]

'Perfect Circle' accreditation Bill? benchmark company with benchmark training. Had to be good for Mahle to want them.

Thing is these days a number of guys don't check ring gaps or even wash a set of rings much less micro examine them,,, out of the packet, look for dots and on they go, some don't even look for the design to match fitment dots, much less understand what the design differences even are. I suppose for a number it does not matter.

Mag, oil ring rails should be barrel faced already, correct me Bill, but i think the original design of three piece oil rings by Mahle was called 'SU50' ?
Detroit two stroke series engines had chrome plated steel rings, these rings could be hammered out straight, then twisted into a pigtail, a ring bent on one end and the other end sharpened into a scriber, now, that's a tough ring.

I can tell a story of an engine having BonAmi poured down the plug holes and cranked in most unusual ways. But it's a bit long.

Cheers.

American Hammered/Sealed Power at one time designated their three piece oil control rings as SS50. Over time the Sealed Power manufacturing plants were sold to SPX Corporation, then to Perfect Circle in 1996, then the ring product was sold to MAHLE in 2007.
The three piece oil ring was first used in mid 1950's Cadillac engines. This style of ring was called the flex vent style and has a gold anodized expander for years, then Perfect Circle designed a "Chem-polished expander, which is bright silver and appears to be chrome plated. Prior to the three piece oil ring introduced in the 50's, most oil rings were one piece cast iron with a coil spring expander behind the ring. Steel one piece oil rings are making somewhat of a comeback in the high performance industry, as the steel one piece ring is much lighter than the cast iron counterpart, and very close in weight to a current three-piece oil ring. Various ring faces can be designed with many options as to the scraper angles, widths, etc.