Piston Rings__Another Lesson Learned The Hard Way

[toobroketoretire]

After buying my pistons and rings from Summit Racing as a "set" and ending up with an oil burner I'll never buy a "set" ever again. From now on I'll only buy American made piston rings like Hastings or Perfect Circle (now owned by Mahle). When I tore my engine down I found all 8 of the pistons had "soft" carbon on their tops that my gasket scraper peeled off like softened paint. The oil rings were about 90% broken in so that indicated their expanders were too weak. My rebuilt engine only has 131 miles on it so far but the oil level hasn't changed enough to notice. I'll know more as the miles increase but I know it'll go a lot further than the 350-400 miles per quart it was getting.

I have been reading about a LOT of oil burning engines lately in other forums and I suspect those engines also got rebuilt with foreign made piston rings. When it comes to our engines I highly recommend using ONLY American made parts.

 

[LLC5]

After buying my pistons and rings from Summit Racing as a "set" and ending up with an oil burner I'll never buy a "set" ever again. From now on I'll only buy American made piston rings like Hastings or Perfect Circle (now owned by Mahle). When I tore my engine down I found all 8 of the pistons had "soft" carbon on their tops that my gasket scraper peeled off like softened paint. The oil rings were about 90% broken in so that indicated their expanders were too weak. My rebuilt engine only has 131 miles on it so far but the oil level hasn't changed enough to notice. I'll know more as the miles increase but I know it'll go a lot further than the 350-400 miles per quart it was getting.

I have been reading about a LOT of oil burning engines lately in other forums and I suspect those engines also got rebuilt with foreign made piston rings. When it comes to our engines I highly recommend using ONLY American made parts.

You do know that Mahle is a German owned company, correct?

Again, in reference to quality it doesn't matter where a product is made, it only matters to what standard it is made to. You can buy American made junk all day long as easy as anywhere else in the world.

 

[LLC5]

After buying my pistons and rings from Summit Racing as a "set" and ending up with an oil burner I'll never buy a "set" ever again. From now on I'll only buy American made piston rings like Hastings or Perfect Circle (now owned by Mahle). When I tore my engine down I found all 8 of the pistons had "soft" carbon on their tops that my gasket scraper peeled off like softened paint. The oil rings were about 90% broken in so that indicated their expanders were too weak. My rebuilt engine only has 131 miles on it so far but the oil level hasn't changed enough to notice. I'll know more as the miles increase but I know it'll go a lot further than the 350-400 miles per quart it was getting.

I have been reading about a LOT of oil burning engines lately in other forums and I suspect those engines also got rebuilt with foreign made piston rings. When it comes to our engines I highly recommend using ONLY American made parts.

And another thing...

Your perpetual bashing of name brand and country of origin products is pointless. You have already proven in your posts and pictures that your oil use issue is not product related, but is talent related. Your junkyard/used car dealer mentality in engine assembly, and the use of hot spotted cylinder walls with JB welded cylinder heads are just a small part of your oil use issue. You have proven through print and pictures over and over again that it clearly not a product issue, so get over it.

 

[kpic]

And another thing...

Your perpetual bashing of name brand and country of origin products is pointless. You have already proven in your posts and pictures that your oil use issue is not product related, but is talent related. Your junkyard/used car dealer mentality in engine assembly, and the use of hot spotted cylinder walls with JB welded cylinder heads are just a small part of your oil use issue. You have proven through print and pictures over and over again that it clearly not a product issue, so get over it.

It could have been too much Bon Ami...

 

[LLC5]

It could have been too much Bon Ami...

Yes, it could have been, cannot rule that out.

And again not a Bon Ami issue, but as always with this OP, an issue with how it was used.

 

[kpic]

Yes, it could have been, cannot rule that out.

And again not a Bon Ami issue, but as always with this OP, an issue with how it was used.

As Wheeler Dealers would say you were "Spot on." The Bon Ami comment was intended for a laugh. As usual, TBTR is a never ending story on what not to do.

 

[dougelam]

And another thing...

Your perpetual bashing of name brand and country of origin products is pointless. You have already proven in your posts and pictures that your oil use issue is not product related, but is talent related. Your junkyard/used car dealer mentality in engine assembly, and the use of hot spotted cylinder walls with JB welded cylinder heads are just a small part of your oil use issue. You have proven through print and pictures over and over again that it clearly not a product issue, so get over it.

Yes, either the cylinders were not preped properly or the wrong parts were installed!

Since it was all 8 my money is on the parts were incorrect/not fitted properly

I don't see where Summit failed

Sent from my SM-N920P using Tapatalk

 

[kpic]

I'd ask how he set the end gaps. However, to be blunt, I don't really want to know.

 

[bill81vette]

I'd ask how he set the end gaps. However, to be blunt, I don't really want to know.

He can probably 'eye' the end gaps

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[Antz81]

Yes, either the cylinders were not preped properly or the wrong parts were installed!

Since it was all 8 my money is on the parts were incorrect/not fitted properly

I don't see where Summit failed

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Since he fitted his engine with the wrong mounts(and then complained they didn't fit properly) I would put my money on him having used the wrong parts.

 

[LLC5]

Since he fitted his engine with the wrong mounts(and then complained they didn't fit properly) I would put my money on him having used the wrong parts.

Or installed used parts to match his scored cylinder walls.

 

[toobroketoretire]

Another 20 Miles

I put another 20 miles on it this afternoon so it now has 155 miles on the new rings and bearings. The oil level on my dip stick has dropped about 1/8" so a little bit of oil has been consumed. My old piston rings would have dropped the level 1/2 quart so things appear to be a lot better. I'd like to put more miles on it but at this present time I just don't need to go anywhere and I can't justify driving it for no reason. It's showing a full 70 psi even at full operating temperature so the high volume pump made a difference of about 20 psi.

My generator engine quit on me this afternoon (I live solely on generator/inverter power because of my remote location). It popped and sputtered for a few seconds then coasted to a stop and it sounded like an ignition failure. Maybe the ignition coil has come loose and that's why it popped and sputtered. I'll look into it tomorrow morning. If it's not my '71 screwing up it's my generator set.

 

[kpic]

My old piston rings would have dropped the level 1/2 quart so things appear to be a lot better.

Do it twice to get it right...

A half quart in 20 miles; I truly understand LLC5's comment:

You have already proven in your posts and pictures that your oil use issue is not product related, but is talent related. Your junkyard/used car dealer mentality in engine assembly, and the use of hot spotted cylinder walls with JB welded cylinder heads are just a small part of your oil use issue. You have proven through print and pictures over and over again that it clearly not a product issue, so get over it.

TBTR, you are truly a legend in your own mind...

 

[dougelam]

(I live solely on generator/inverter power because of my remote location).

That explains the lack of modern knowledge!

The information highway doesn't go that far yet

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[kpic]

That explains the lack of modern knowledge!

Doug,
Please allow me to correct that; it is the total lack of any knowledge.

TBTR: I'll be blunt from our Master Techs, advanced hobbyists and even me, who spent 45 years in design engineering; you are an insult our professions.

 

[LLC5]

It's showing a full 70 psi even at full operating temperature so the high volume pump made a difference of about 20 psi.

As usual you don't get it. Oil pressure at 70 psi hot is too much, and can damage what you already haven't in your engine.

Where did you get any information anywhere that led you to believe that oil pressure at 70 psi hot is a good thing?

You have messed up yet again.

 

[Antz81]

As usual you don't get it. Oil pressure at 70 psi hot is too much, and can damage what you already haven't in your engine.

Where did you get any information anywhere that led you to believe that oil pressure at 70 psi hot is a good thing?

You have messed up yet again.

I was reading about this a little while ago. What was said about high oil pressure was straight to the point. High oil pressure can be as bad if not worse than low oil pressure. This was followed up with an explanation as to why.

 

[toobroketoretire]

Oil Rings

If you look closely at new oil rings you'll notice they have a 1/2 round face and as that face wears it becomes completely flat at around 50,000 miles. Before they wear completely flat they have a tendency to "hydroplane" over the oil and that oil ends up getting burned. But flat or not the rings require a certain amount of tension to keep them firmly against the cylinder wall and if there isn't enough tension they'll allow oil to pass by them. There is a lot of engineering involved in designing the expanders and for the minimal $35 it costs for American made rings it's just not worth using Chinese made rings and worrying if they'll do the job.

 

[LLC5]

If you look closely at new oil rings you'll notice they have a 1/2 round face and as that face wears it becomes completely flat at around 50,000 miles. Before they wear completely flat they have a tendency to "hydroplane" over the oil and that oil ends up getting burned. But flat or not the rings require a certain amount of tension to keep them firmly against the cylinder wall and if there isn't enough tension they'll allow oil to pass by them. There is a lot of engineering involved in designing the expanders and for the minimal $35 it costs for American made rings it's just not worth using Chinese made rings and worrying if they'll do the job.

Exactly what engineering class did you learn this at?

 

[Hib Halverson]

So, uh...let me get this straight:

Without doing a careful oil consumption test, on the basis of finding "soft carbon" deposits on piston tops, you have decided the rings Summit Racing Equipment includes with their piston sets are faulty?

Ok. Some questions

1) Are these "soft carbon" deposits from an engine which is running rich at idle and/or part throttle or are they oily carbon deposits from an engine which is using oil?

2) Was the piston set advertised as having low-tension oil rings?

3) What's the level of taper of the bores?

4) How were the cylinder walls prepared?

5) What's the piston-to-bore clearance?

6) Any chance the second ring (the oil scraper) is installed upside down?