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Subject: Piston ring questions

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BW    Posted 10-13-2020 at 17:53:05 [URL] [DELETE]        [Reply] [Email]  
  • Piston ring questions
  • Have an engine off a 50 8n torn down, looks pretty decent (sleeves,Pistons crank ect). Will confirm some specs when I get a proper caliper but I sent a piston with a buddy so he could measure things up for now and he measured it as follows:
    It has the 4 rings, standard bore size, two compression rings measure 0.093 but the oil rings were measured at 0.153. Anywhere that I have looked on line has the 4 ring pistons measuring 0.187 on the oil rings. Some 3 ring kits have a 0.156 oil ring but none of the 4 ring kits do.
    I will need to reconfirm the #ís but was wondering if anyone new if this was a normal setup?
    Thanks in advance

    Bruce(OR)    Posted 10-16-2020 at 06:56:30 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Piston ring questions
  • Original engine was a 4 ring job. New rebuild kits eliminated 4th ring.
    4th ring was additional oil wiper to prevent oil into cylinder.

    BW    Posted 10-16-2020 at 07:06:56 [URL] [DELETE]        [Reply] [Email]  
  • Re: Piston ring questions
  • Thanks Bruce...are you saying it would be ok to run the original pistons without the 4th ring in place?
    Wasnt really wanting to replace the pistons as they are in excellent shape but having trouble finding a complete set for them

    Bruce(OR)    Posted 10-16-2020 at 08:48:17 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Piston ring questions
  • Reminds me of a fella who took his '64 Caddy into a shop for an engine job.
    Used the same old pistons with new rings and bearings. A few days after he got his car back, the engine went poof.
    That 4th set of rings I believe are currently made of unobtainium found in then country of obsoleteum. Not running those rings could result in piston wobble and more problems.
    In for a dime, in for a dollar.

    BW    Posted 10-17-2020 at 09:59:30 [URL] [DELETE]        [Reply] [Email]  
  • Re: Piston ring questions
  • Bruce
    What I was really wondering was if anyone had seen the 4 ring pistons with the smaller size oil rings, cannot find mention of it anywhere.
    Didnt want to reuse the rings but pistons were good. No matter now anyway, pulled the thin wall sleeves last night so it will now be getting a complete, new sleeves, pistons, bearings, the works!

    TheOldHokie    Posted 10-17-2020 at 18:59:01 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Piston ring questions
  • That would be the best choice possible.


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