Determining second ring and oil ring condition

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Belgian1979
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Determining second ring and oil ring condition

Post by Belgian1979 » Wed Sep 27, 2017 1:41 pm

Is there a way to determine their condition on an assembled motor ?

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Re: Determining second ring and oil ring condition

Post by pamotorman » Wed Sep 27, 2017 3:34 pm

Belgian1979 wrote:Is there a way to determine their condition on an assembled motor ?
since the second ring is a oil scraper and the oil ring is there to control oil usage how much oil the engine uses. when GM had oil usage problems with the LS corvette engines the warranty fix was a new type second and oil ring with the top compression ring re used .

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Re: Determining second ring and oil ring condition

Post by Belgian1979 » Wed Sep 27, 2017 4:14 pm

Ok, but how do you know they are bad ?

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Re: Determining second ring and oil ring condition

Post by pamotorman » Wed Sep 27, 2017 5:22 pm

Belgian1979 wrote:Ok, but how do you know they are bad ?
by how much oil the engine uses compared to other engines of the same build.

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Re: Determining second ring and oil ring condition

Post by engineguyBill » Wed Sep 27, 2017 5:25 pm

There is no positive way to tell that a specific ring is bad without removing the piston/rings for examination.
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Re: Determining second ring and oil ring condition

Post by pamotorman » Wed Sep 27, 2017 6:53 pm

one of the tricks back in the 5 HP briggs go kart days was to leave out the second ring and reduce the tension on the oil ring and mix some nitroethane in the crankcase oil. oil sucked into the combustion chamber helped with the HP. :D

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Re: Determining second ring and oil ring condition

Post by Newold1 » Wed Sep 27, 2017 8:02 pm

EngineguyBill's answer X 2.
Remember that the preparation and condition of the bores themselves will have more to do with how well the second ring and oil ring are doing their job.
If you've got an oil consumption problem from the second and oil ring sub par performance you are going to have to at least remove a head and inspect, measure and determine what went wrong with the bore and ring package as a group and then correct the mistakes or problems in all the bores with most likely new bore finishes and ring replacements.

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Re: Determining second ring and oil ring condition

Post by MadBill » Wed Sep 27, 2017 8:35 pm

A borescope down the plug hole would be a worthwhile first step to check wall condition.
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Re: Determining second ring and oil ring condition

Post by Belgian1979 » Thu Sep 28, 2017 3:50 am

MadBill wrote:A borescope down the plug hole would be a worthwhile first step to check wall condition.
I already did that and it seems ok, but difficult to see all sides. I can still see the honing marks.

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Re: Determining second ring and oil ring condition

Post by Belgian1979 » Thu Sep 28, 2017 3:53 am

Newold1 wrote:EngineguyBill's answer X 2.
Remember that the preparation and condition of the bores themselves will have more to do with how well the second ring and oil ring are doing their job.
If you've got an oil consumption problem from the second and oil ring sub par performance you are going to have to at least remove a head and inspect, measure and determine what went wrong with the bore and ring package as a group and then correct the mistakes or problems in all the bores with most likely new bore finishes and ring replacements.
Block was bored and honed with deckplates. Piston clearance was well within limits. The ring gaps were set in the bore gauge and filed to suit. The marking on the second ring was pointing to the top as required. Not sure what more I could have done. Only thing left could be the honing process itself or the fact that the oil control ring rides on a support rail since the pin intersects with the oil ring.

On a side note the engine produces very high decel vacuum as I stated earlier in some of my threads. Would this in some way be indicative of second and oil ring condition ?
PS : compression test was ok. I have been through the valve guides and I'm going to have them done as some wiggle meaning there is too much clearance. I changed the valve seals while I was in there. At the moment spark plugs are less oiled up, but I'm still loosing oil. Have to add that I also reconnected the PCV.
The problem I also have is that there is an accusump and I'm not sure if what it holds is always constant....

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Re: Determining second ring and oil ring condition

Post by mag2555 » Thu Sep 28, 2017 6:19 am

Belgian 1979 you have been posting about solving a oil usage issue for like a year now so for Gods sake pull the motor down and freshen it up, as it's all getting a little bit old for me!
I use to be a procrastinator too and then got fed up with no winning races, so don't be that guy!

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Re: Determining second ring and oil ring condition

Post by n2xlr8n » Thu Sep 28, 2017 6:37 am

As I mentioned in your other post: Vacuum pump.

Before I pulled it down, I'd see if a cheap corvette pump helped your oil control situation.
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Re: Determining second ring and oil ring condition

Post by joe 90 » Thu Sep 28, 2017 8:13 am

You probably bore washed it through having a real shitty tune.

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Re: Determining second ring and oil ring condition

Post by Truckedup » Thu Sep 28, 2017 8:59 am

This may or may not be relevant to the OP's problem....Many classic/vintage bike engines use gray top and second rings. The second ring has a tapered face to scrape oil ..Sometimes these are installed upside down due to installer mistakes or lack of top of the ring marking...
Naked frame LSR bikes, dressed in animal hides clinging to machines propelled by fire...

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Re: Determining second ring and oil ring condition

Post by steve316 » Thu Sep 28, 2017 9:14 am

Order a napier second ring & install. time well spent.

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