Seating piston rings
Thread Starter
Safety Car
Joined: Mar 2000
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From: Central Pennsylvania
Seating piston rings
I’m in the process of rebuilding a 327 that’s getting punched out .030. Arguably the most critical operation after rebuild is seating the rings. How have you guys achieved good piston seat on your rebuilds? Run a full load of motor oil for the process? If so any additives? Or do you just give the cylinder walls a coating of oil etc during rebuild and do your initial start up with a dry oil pan. I even remember some old timers swearing they started the motor bone dry and just gave the throttle a few quick shots then shutting down to get a seat. Tips, tricks, suggestions?
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Army
Thread Starter
Safety Car
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From: Central Pennsylvania
Haven’t chosen them yet. Nothing exotic. Basic old technology standard cast probably. Maybe nitride at the most. Kinda wanna stick with familiarity and proven, time tested technology.
Burning Brakes
Joined: Jun 2005
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From: Hinesville, GA & Oswego, NY
I certainly do not recommend starting an engine bone dry for any reason. Today's rings don't give much problem seating, the machine shop will hone your cylinders with the proper pattern to allow the rings to seat quickly.
Fill the oil pan and filter with oil, fill the block and radiator with coolant, fire it up normally, if you are breaking in a new cam and flat tappet lifters keep the RPM at cam manufacturers recommendation, by the time you have run long enough to break in the cam and lifters the rings will already be seated.
Bill
Fill the oil pan and filter with oil, fill the block and radiator with coolant, fire it up normally, if you are breaking in a new cam and flat tappet lifters keep the RPM at cam manufacturers recommendation, by the time you have run long enough to break in the cam and lifters the rings will already be seated.
Bill
Last edited by Bill Pilon; Jan 10, 2019 at 09:24 AM.
Safety Car
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From: Olive branch Ms
I'm very picky about what brands of parts I will use in an engine. For rings there is only one choice Sealed Power moly rings. For your application if you have standard ring widths and depths is E251K.030. They are cheap cheap cheap. Do not try to save $10 by using cast rings. If your cylinders are properly prepared the rings will be seated before you let go of the key and you can worry about something else. You can get the under $40 with free shipping. The only draw back to them is they are now made in Mexico. But your other choices are still worse. You should be asking your machine shop rather than a forum but if they give you a different answer in this case you should still get the Sealed Power.
Dude I just reread the part about starting it dry. NEVER EVER EVER ask these guys another question about anything let alone an engine. You do not start an engine dry or you won't be worrying about rings. All of your bearings will be toast and your fresh cylinders and Pistons will be scuffed to trash!
Dude I just reread the part about starting it dry. NEVER EVER EVER ask these guys another question about anything let alone an engine. You do not start an engine dry or you won't be worrying about rings. All of your bearings will be toast and your fresh cylinders and Pistons will be scuffed to trash!
Last edited by Robert61; Jan 10, 2019 at 09:27 AM.
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Safety Car
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From: Central Pennsylvania
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Standard tension ring sets with a moly faced top ring have been OE since the seventies. In the fifties/sixties typical chrome faced top ring sets needed a "break-in" period, but moly rings seat very quickly, and don't really need a thoughtful break-in. Chrome-faced top rings are much harder and abrasion resistant than moly, but modern cellulose air filters are so efficient at removing tiny particles that chrome faced rings are no longer necessary.
The basic break-in procedure is to vary speed and load for the first few hundred miles up to about 3500 to 4000 and avoid high sustained load. As I said it's not really necessary with moly rings, but will certainly do no harm.
Cast iron rings are fine on a race engine that will be rebuilt frequently. They seat almost instantly, but don't have the longevity of moly.
Duke
The basic break-in procedure is to vary speed and load for the first few hundred miles up to about 3500 to 4000 and avoid high sustained load. As I said it's not really necessary with moly rings, but will certainly do no harm.
Cast iron rings are fine on a race engine that will be rebuilt frequently. They seat almost instantly, but don't have the longevity of moly.
Duke
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From: When all is said and done... there is a hell of a lot more said than done. Riverside,Texas
St. Jude Donor '05 thru '26
Proper cylinder honing is most important, along with good cylinder cleaning and a coat of light oil. Run the engine above 1500 rpm and vary the revs.
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Safety Car
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From: Central Pennsylvania
Safety Car
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Yes I've used tons of them, they are fine. Here's a list I try to refuse to vary from. In some cases you have no choice but to use other brands because they are not available. But for the 327 everything is available.
gaskets. Fel Pro
bearings. Michigan 77
cam bearings. Durabond other brands are ok they are just my first choice
rings Sealed Power
lifters if you are running a hydraulic. GM they cost a little more but you are insured they've undergone quality control testing anything else and these days you have no idea where they come from
oil pump. Melling 55 this is sure to get another row started but I remove the stock spring and stretch it 1/4" or replace with a pink spring also use the oil pump drive with a steel guide instead of the nylon stock one. They are available at most parts stores under Melling. It is also a good practice to set the oil pump screen 3/8"-1/2" from the bottom of the pan and tack weld it.
if you are replacing rocker arms and pushrods. Elgin. They make a lot of internal engine parts and all are of good quality.
Last edited by Robert61; Jan 10, 2019 at 10:05 AM.
Thread Starter
Safety Car
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From: Central Pennsylvania
Originally Posted by Robert61
It is also a good practice to set the oil pump screen 3/8"-1/2" from the bottom of the pan and tack weld it.
Race Director
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From: Long Island
I broke my 71's engine in on a dyno. It's the original motor rebuilt. The engine builder - took my engine set it up on the dyno. Put a squirt of oil in each cylinder, spun the oil pump ( I used break in oil + Zedd. ) with a drill until we had pressure, turned the engine over by hand once. Put in the distributor, and started it. After it reached operating temp let it run at 1800 rpm for 15 minutes. It's a roller motor.
Let it cool , restarted it, let it run 5 min and then did the pulls to tune it.
Motor runs excellent…
Last edited by BLUE1972; Jan 10, 2019 at 01:12 PM.
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I agree - Cleaning after honing takes some time, not just a quick wipe. After honing put some oil on a rag (or paper towels) and wipe on each cylinder, keep doing this repeated times until the rag is perfectly clean after wiping.
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I would say the most critical part si cam break in.
I used in the past, a can of good old GM EOS on the lobes and lifters and poured the rest in the pan with the fresh oil, primed the oil system with primer tool, installed the dizzy and fired it up and ran at 2000 RPM for 20 minutes.
On rings, i just shot a small squirt of light oil into the cylinder bore through the spark plug holes prior to manually rotating the engine to set the valve lash.
Doug
I used in the past, a can of good old GM EOS on the lobes and lifters and poured the rest in the pan with the fresh oil, primed the oil system with primer tool, installed the dizzy and fired it up and ran at 2000 RPM for 20 minutes.
On rings, i just shot a small squirt of light oil into the cylinder bore through the spark plug holes prior to manually rotating the engine to set the valve lash.
Doug
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I would say the most critical part is cam break in.
I used in the past, a can of good old GM EOS on the lobes and lifters and poured the rest in the pan with the fresh oil, primed the oil system with primer tool, installed the dizzy and fired it up and ran at 2000 RPM for 20 minutes.
I used in the past, a can of good old GM EOS on the lobes and lifters and poured the rest in the pan with the fresh oil, primed the oil system with primer tool, installed the dizzy and fired it up and ran at 2000 RPM for 20 minutes.
Instructor
Joined: Jul 2013
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From: Gig Harbor, WA
If you use the Sealed Power moly rings, and you turn the engine over during by hand during assembly, they will be broken in before it's started for the first time. I'd be more concerned about the cam and lifters.
Steve
Steve
Last edited by seb67; Jan 10, 2019 at 10:16 PM.