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Discussion Starter · #1 ·
Hey guys,

As some of you know I have had issues with my engine that required a rebuild. The engine had about 5 hours run time on it before the bearing problem. I have the parts all back and I am trying to decide whether or not to buy a new set of rings. My first machinist that screwed the thing up says that they should be okay and will reseat. While he did screw up, he does do alot of work with race engines that get frequent rebuilds so he does have some idea about this. The other machinist that fixed everything and retouched the hone on the cylinders thought it to be a bad idea to run the used rings. So I have two opinions so far.

It I was not running CA zero gaps, I would not hesitate to buy another set. With the price of these rings, I would like to reuse them if it is not a problem. It seems to me like they should wear in fine, but I want to get some of your opinions on this. Any previous experience would be appreciated.

Chris
 

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Your probably ok using them again as long as Each piston and ring set go back in the same cylinder they came out of. Iv'e done it before on my own engines and it's worked fine. If your building an engine for someone else it becomes cost & pr problem. If you build it and just one ring doesn't seat youv'e got an upset customer and you'll be doing it over $$$. I have a feeling that coated rings would be a whole different game. :thumbup:
 

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If it was honed again I would throw in some rings, they aren't designed to be broken in twice.

Cheap insurance.;)
 

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what if they still have the disease that infected your old motor... i mean...

THEY COULD INFECT THE NEW ONE?!

Gecha some new ones man, you said yourself molly rings seat in the first couple minutes. Using a ring that's seated against one bore in a different bore is like running your motor, taking the bearings out and swapping them into different journals. Just doesn't seem like a good idear.

K
 

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With only 5 hours operating time on the rings, I would not hesitate to reuse them. If you had put the mic on them before installation and were to re mic now, there would not be any detectable wear. With the rehoning of the cylinders, I would expect the rings to seat in just as nicely as if they were 0 time rings.

Trees
 

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The Smell of Nitro in the morn
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Ditto with Chuck & Killer, save the rings for a different motor to beat. Look at the rings under a magnifying glass and you will see the scratches. Its not worth using the old set with a new motor.
I would really wash the oil holes in the rods to make sure all the junk is out of them, and oil the crap out of them for the wrist pins.
 

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Hey turbo, nice to see your getting things back together. As some people just posted it may be fine but for all the problems you just had and all the pain and suffering you just had, Im suprised your even asking this.

Im with Killer just buy a new set and eliminate all doubt.

Ben
 

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I've seen it done before and most of the time it works if the cylinders are not honed and the rings go back in the same cyl that they came out of. If the block has been honed I'd have to think that the ring life would be affected.
 

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"May the Schwartz be with you"
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Is your engine worth a guess? Probably not. Rehone the cylinders and install new rings. This is too cheap of an item to take a chance.

If you want to assume they will be ok, just remember that the word assume broken down is...makes an *** out of U and ME.


I see the first part was censored, but I think you all know what I mean.
 

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Discussion Starter · #11 ·
Well, I have known guys that tore down race engines, touched up the hone and put them back together with the same rings. But, I dont know that they seat properly doing that. I do know that the rings seat very quickly, but I just dont know if they would reseat on a new bore. As for being a cheap item, price a set of CA zero gap rings.

I am waiting for a couple of the machinist to chime in. I was leaning toward replacing them before I posted, but I dont want to replace something that does not need to be replaced when we are talking $200.

Chris
 

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Well, I am giving you a thought based on the fact that I am a licensed engineer and a machinist. The rings have a tendency to do a bit of shuffleing in the bore prior to finding a home (this is called seating).

What is supposed to happen is that the grooves put into the cylinder walls are supposed to wear into the rings leaving a high area for the rings to ride on and a low area for containment of oil for lubrication purposes.

In this process of wear the rings will rotate to some extent (this is where you hear about the gaps lining up). You are best to start with fresh rings and a fresh cylinder crosshatch to negate any detrimental consequences due to the issue that you have had.

I am pretty sure that $200 is less than the cost of the engine to date.
 

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I had the Total Seal Zero Gap rings in my 406, they were about $135 from Scoggin-Dickey. For some reason #6 didn't seat/seal. I called Total Seal and ordered one set of rings for $31!

Like you, I got differing opinions on whether the old rings would reseat. I just did it for peace of mind.
 

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Will I ever get it done?
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You didn't say what you are doing with the engine. I knew a low-buck racer who had a bantam altered with a 350 in it. He bracket raced it, so optimum performance was relative. At one point he put the engine back together with used compression rings from one motor, second rings from another, and oil rings from a third. Ran great. Won money with it.

But if you are putting together a race motor for a specific class or a 100,000 mile street motor, new rings are relatively cheap compared to the risk of loss.
 

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Turbo,


I would have to think you could just re-install the rings.

I'll expound just a little bit on ring function. Piston rings have come a long way from the old days, and alot of the things that worked in the 60s don't pertain to today's engines.

OEM's and racing engine builders all know that a rings sealing ability depends upon cylinder roundness and smoothness with today's modern ring technology. The old Hastings black iron rings are for backyard rebuilds, your specialty rings are not.

If you are paying attention to what is being done with honing techniques today, you'll notice that machine shops are trying to duplicate an already "broken in " cylinder bore, which is a very smooth finish.

If your original bore finish was done in this manner, I will have to say that in all probability, the rings have no perceivable wear on them with 5 hours run time.


However, I do seem to remember that your machinist failed to torque-plate hone your block initially. Has this been corrected?

Perhaps you should torque a head onto the block without the reciprocating assembly and check for out of round from the bottom side. This will tell the story. If it's within a thou of being round with the head on it, I'd call it good.

If you've had it re-honed with a plate, and it's round and has the proper finish, I wouldln't hesitate to re-use the rings as long as they aren't scuffed.

5 Hrs of run time is nothing.
 

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Come Home Safe Soldier
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You put a lot of time in your setup Turbo.I did not read all the posts but am willing to bet that most said the same thing.I would install new rings,that was a pretty nasty mess that you had last time.I would be afraid to use the same rings.Good luck bud,hope shes screamin soon.
 

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NAIRB, I agree with you except I get the perception that he doesn't have a lot of $$$ to throw around and this leads me to believe that he wants the engine to last. In this case and due to the incorrect machining procedures done and due the the fact he had a bunch of junk floating around in his engine, I would definately recommend starting over with new.

He most likely could get away with the old rings, but I question whether or not he could identify a problem with them (if any) to any degree of accuracy.

This is just my opinion.
 

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Discussion Starter · #20 ·
NIARB,

Yes, there was a torque plate issue. I had the hone touched up but not plate honed. The machinist said he would have to remove .002 or .003 to get it back in round with plates so we decided to leave it as is. You are describing what I found after looking at the net on the ring breakin. The wear is in the cylinder walls and not the rings.

Chris
 
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