Piston rings glazed

...Piston Rings are Lubricated by 'Splash' from the Crankshaft.
10 Hours at Idle!?

That is Not the Way to 'Seat' New Rings. In My Opinion. I was Always advised, when First Firing a Newly Built Engine, DO NOT Let it IDLE!! Run it in, with Differing RPM for 30 Minutes, and then take it out on the Highway and do the same for 100 Miles. DO NOT 'Lug' the Engine! Then come back and change the Oil.

I use TRW Forged and Coated Pistons with SpeedPro Chrome-Moly Rings. The TRW Installation Instructions state the Clearance at a Max. of .002"

Hi Peter -

I am with Marlin, I always had heard (and used) at least 20 min at various RPMs (over 2000 RPM) to break in the motor.

Let us know as you do more investigation.

hope you don't mind me jumping in and trying to learn some.

But is it the rings that glaze or is it the cylinder walls?

Rather than blaming the piston rings for being poor quality, I would like to suggest that you figure out what was wrong with the manner in which the engine was assembled or broken-in, so that the problem is not duplicated a second time.

Yes thats right George! In fact , we did a lot of engines in the past and always use mahle rings. When the oil preassure is ok, it was always ok , when audi or bmw or toyota engines were running longer times on idle. Sometimes , I let them run a few secounds at high rpm , but most of the time they run idle . Thats what I did in the past and I had never a problem like this.
Normaly, when I repair a engine, I buy the parts from Rothmund and the sales agend give me the "good stuff". Never had piston rings, wich do no compression , when they are new , or running for a few hours!? For only 20 bucks more they sell moly rings, so why they sell "cast" -rings ?

All the work 4 nothing - ok this time I use moly rings , and will drive with the car for brakein. Maybe a carburated engine is diffrent to modern engine.
What rings would you suggest ? Does somebody drive cast rings ? Thanks

Marlin Hi
agree on the model reving the engine up and down ..not to high but NOT to low ..low is more danger as to my knowledge on rebuilding old Porsche engines resulted in "an oval" on the mains. Hence no good.
I used to rev the engine up WHILE DRIVING and down all the time. Which is what Chuck is saying as well
GUESS THAT IS WHAT YOU MEAN BY "LUG = constand rpm" the engine?
TX
Matthias

quote:

Originally posted by GT4Peter:
Yes thats right George! In fact , we did a lot of engines in the past and always use mahle rings. When the oil preassure is ok, it was always ok , when audi or bmw or toyota engines were running longer times on idle. Sometimes , I let them run a few secounds at high rpm , but most of the time they run idle . Thats what I did in the past and I had never a problem like this.
Normaly, when I repair a engine, I buy the parts from Rothmund and the sales agend give me the "good stuff". Never had piston rings, wich do no compression , when they are new , or running for a few hours!? For only 20 bucks more they sell moly rings, so why they sell "cast" -rings ?

All the work 4 nothing - ok this time I use moly rings , and will drive with the car for brakein. Maybe a carburated engine is diffrent to modern engine.
What rings would you suggest ? Does somebody drive cast rings ? Thanks

Some recommend a combination. Molly on top, cast iron on #2.

I generally use molly on both. I'm not seeing where there should be any kind of issue unless the cross hatch on the honing is wrong?

I don't disagree with the break in recommendations but the reality is that they are seated within 5 minutes of start up and to do that you need to keep the engine running which means probably something around 1800 to 2000 rpm.

It's like something you would see with a cold start and fast idle until warmed up. That's enough right there and once you can get it to idle down without stalling the rings are done seating themselves.

I agree with Doug. Coincidently, there's an extensive thread on engine break-in on my Engine Builders Forum right now (www.speedtalk.com). A half-dozen pro builders disagree on details but nearly ALL agree that the best way to break in a new engine is on a dyno; after warm-up, by the third pull under load to maybe 5000 rpm the power stabilizes and rings & valves are seated as well as they will ever be. Good quality moly-faced rings break in almost immediately per the above. Old-school cast iron rings are cheap, for easily satisfied poor boys with time but no money and need to be prepped as we did 50+ years ago.

Others say to break in a street engine by immediately driving it as you expect to use it in the future. All agree- do NOT let it idle AT ALL and do not use synthetic oil during break-in. Change oil & filter after 50 or so miles & inspect for debris. Engine break-in is essentially rapid, controlled wear of the new parts, and modern synthetics & additives are especially designed to prevent this!

by dis-assembling the engine you lost the opportunity to properly diagnose the problem, pretty difficult to perform a cylinder leakage test with the heads off

get the valves vacuum tested for sealing,

and what was the lifter lash / preload set at?

Hi Matthias -

"Lugging" the engine - "To lug" means to drive the engine in too high of a gear.

With the 351C, you have so much torque that you can drive around slowly, at low RPM in high gear. This is lugging the engine.


We are recommending not to do this during the break-in period.

Tx Chuck!
well the language of the experts is not necessarily clear to non natives, and I guess even for normal US folks..

Your definition provided fits my pattern!
..break-in will happen within next 2 month..as car is nearly restored...but we still have Winter..

Matthias

quote:

Originally posted by Mat_G:
Tx Chuck!
well the language of the experts is not necessarily clear to non natives, and I guess even for normal US folks..

Your definition provided fits my pattern!
..break-in will happen within next 2 month..as car is nearly restored...but we still have Winter..

Matthias

Normal? I don't know if I like that term? Do you honestly think that anyone in the US (or anywhere else) that can put up with a Pantera is NORMAL? You are kidding, right?

I think I might be insulted?

Matthias !

I don’t know if I should by insulted by you calling me an “expert”!!!






Smiley Face!


Chuck

What can I say..as a Pantera new comer?!! There is so much expertise and experience within the nice US team that what ever ME at least can say you folks are Experienced with the facts and goodies of our NICE Monsters (due to Term Panter vs cat - I do not want to go into direction of questioning beeing NORMAL to deal with it ). It might sound ironic to call long gained experience on the Monster by the team as EXPERTS, no non of that .. is just a term I used to appreciate your inside and willing to expose it!

Well yes sometimes "so called" Experts go far out on an explanation which appears a bit too scientific (if I leave it on that level for now), well I take it with a positive smile..got a very long carrier in high end technology.. well sometimes I did feel like an Expert and might even been called an Expert but next day no more.
To me it is only the honesty to deal with the topic and offer "EXPERTISE"..so for me at least an "EXPERT" for the day..

Tx anyways..will continune to poke you on YOUR "Expertise!!!"

Matthias

Well I suppose if Mick Jagger can stand being "Knighted" and given a title of "Sir" I can stand being insulted by being called normal.

A "monster"? Hum? Maybe? I have to think about it?

It occurred to me as I was reading the forums today that rings that won’t seal properly are possibly as sign of a crankshaft that is unbalanced or incorrectly balanced.

I thought I'd throw that into the mix.

quote:

Originally posted by George P:
It occurred to me as I was reading the forums today that rings that won’t seal properly are possibly as sign of a crankshaft that is unbalanced or incorrectly balanced.

I thought I'd throw that into the mix.

It is also crankcase vacuum/pressure related. The rings will seal much faster with a negative crankcase pressure of about 10 inches.

It's easier to measure that with a vacuum gauge so simpler to state that in inches but 1 inch of vacuum is approximately 1 psi of negative pressure.

If for some reason the engine has a positive pressure like could happen with a supercharger then the tension that the rings naturally provide will be counteracted by that pressure.

A blow through supercharger system will pressurize the crankcase also.

So make sure that you have a functioning pcv system at least until the engine is determined to be "seated".

quote:

Originally posted by PanteraDoug:

... 1 inch of vacuum is approximately 1 psi of negative pressure ...

Not even close. 1"Hg = 0.49 psig

quote:

Originally posted by George P:

quote:

Originally posted by PanteraDoug:

... 1 inch of vacuum is approximately 1 psi of negative pressure ...

Not even close. 1"Hg = 0.49 psig

What's a psig?

If you say so. I know that with the supercharger 1 atmosphere is the weight of the atmosphere at sea level. That's taken as a standard 14psi.

Ooo, now you made me forget how many inches of vacuum that is?

If you look at the supercharger gauges, some are marked in atmospheres and psi.

3 atmospheres is around 35-37 psi in reality. That I saw running in a SB Chebbie and I couldn't get the conversion numbers right? We couldn't figure out what it would take to blow out the head gaskets...but I digress.

As I said, I look at it in inches of vacuum since that's how my gauges are marked on the vacuum side but once they go to boost they are marked in psi.

I'll get out a caliper and measure the increments of both and make a conversion factor and tatoo it on my far head...wait, I won't be able to see that? Scratch that idea.

12 inches is about all the seals like the crankshaft can take without getting sucked in so the thought is for a safety factor 10 inches is a good number to aim for?

Venting the crankcase through the headers only yields around 4 inches of vacuum and that is at high rpm basically.

Every engine needs crankcase vacuum to seal the rings or maybe more correctly make them work right.

So I'm off "just a little" on my conversions? So shoot me? Just don't tell Marlin. He'll be sending me dirty emails.

...YOU were 'WRONG'??? PSIG = Pounds Per Square Inch (reading taken at the ) Gauge.

Atmospheric Pressure at Sea Level is 14.7 PSIG, how many of You have realized, That number also represents the Perfectly Tuned Stoichiometric RATIO of Air to Fuel 14.7:1.

I do concur with Doug about the PVC Valve.
I put My PVC system back on permanently. I did not like seeing the 'Blow-By' Spuing Out of the Breathers, in the rearview mirror. But, I designed and use 'Vapor Separators', at both valve covers to prevent the 'Intake' of Oil. So The Oil Level does Not Recede Down the Dipstick. Vacuum in the Crankcase, as Doug reminded Us, Helps to Seal the Rings and Restricts Excess Oil from Burning.

...And NO, I do Not send dirty emails! I just send the Boys out to Do You Body Damage!!

Body damage? you would hurt a Pantera? Savage!

In the old days of multi-carbed flat heads, the magic fix for glazed rings usually from over carburetion could be corrected by removing the air cleaner turn your idle up to 2500 then with a couple of teaspoons of "Bartenders Friend" (a very mild abrasive powder used to clean pans sinks etc.) blow it into your carb. I was told this but never did it. I did find that the reason was a blown power valve, that was washing down the cylinders. I installed a new power valve ( about $6.00 )and the rings sealed. Their are no magic fixes.

quote:

Originally posted by PanteraDoug:

... Every engine needs crankcase vacuum to seal the rings or maybe more correctly make them work right ...

too much vacuum applied to a crankcase will prevent the oil pump from pumping oil.

quote:

Originally posted by PanteraDoug:

... So shoot me ...

Don't tempt me

quote:

Originally posted by George P:

quote:

Originally posted by PanteraDoug:

... Every engine needs crankcase vacuum to seal the rings or maybe more correctly make them work right ...

too much vacuum applied to a crankcase will prevent the oil pump from pumping oil.

quote:

Originally posted by PanteraDoug:

... So shoot me ...

Don't tempt me

Yes, but the number is thought to be less than 12 inches. 8-10 is what to aim at.

That is what a functioning pcv system should provide.

Should I duck?

quote:

Originally posted by George P:..
too much vacuum applied to a crankcase will prevent the oil pump from pumping oil....

I KNOW I should stay out, BUT I can't help myself.

would the reason for that be the vacuum begins to pull the entrained air out of the oil causing it to foam up.

I was wondering about the use of an abrasize in the combustion mix to seat rings. How about a solvent to wash off the wall glaze

quote:

Don't tempt me

I busted up laughing when I read that one!

I am still chortling about it!

Rocky

quote:

Originally posted by Rocky:

quote:

Don't tempt me

I am still chortling about it!

Rocky

Your a/f ratio could be off?

getting back to the question, you broke the engine in the wrong way, this maybe why your rings did not seal, but, since you are doing all this for the first time follow the instructions referenced by Jack ( boss wrench ). Your rings will seal in time providing your air fuel ratio is correct. Running to rich ( to much fuel ) washes down the cylinders eliminating the oil that seals the rings to the cylinder wall, this is called glazing and is normally again caused by a blown power valve, incorrect over jetting or in a word your carburetor.

Hate to throw something in the mix and it appears you have built a bunch of engines but i wanted to just add one thing. Rings have a bevel an it matters if it is facing to the top or bottom of the piston. I'm sure you checked that.

That's why the rings are marked "top" on the top.
Clever hey?

the rails of the 3 piece oil control ring act as springs, if you hold the circular rail at your finger tips and squeeze inward the ends at the gap will always spring the same way ....

which way do you orient the deflection?

all the same pointing upward

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all the same pointing downward

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opposed pointing toward each other

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opposed pointing away from each other

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