What is the Rear Main Seal of choice today? - NCRS Discussion Boards

What is the Rear Main Seal of choice today?

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Dennis H.
    Expired
    • September 30, 2005
    • 226

    What is the Rear Main Seal of choice today?

    Out looking for information on a rear main seal and my default brand has always been Fel-Pro. I see the term fluoroelastomer thrown around and FEL-PRO part number 2912 but that seems to be a discontinued item now.

    What is a good FEL-PRO part number for a quality seal?

    Thanks
    Dennis
  • Mark E.
    Extremely Frequent Poster
    • April 1, 1993
    • 4537

    #2
    Re: What is the Rear Main Seal of choice today?

    Look for a 2020 thread by Harry Sadlock titled rear main seal. The recommendation is Fel-Pro 2912 for small blocks. I used the equivalent big block variety with good result.

    How it's installed is even more critical. Follow the shop manual carefully. I recommend anaerobic sealant (not RTV) for the area specified for sealant at the main cap/ block interface.
    Mark Edmondson
    Dallas, Texas
    Texas Chapter

    1970 Coupe, Donnybrooke Green, Light Saddle LS5 M20 A31 C60 G81 N37 N40 UA6 U79
    1993 Coupe, 40th Anniversary, 6-speed, PEG 1, FX3, CD, Bronze Top

    Comment

    • Dennis D.
      Extremely Frequent Poster
      • March 1, 2000
      • 1071

      #3
      Re: What is the Rear Main Seal of choice today?

      2912 is disco.GM 10121044 is the exact same seal.
      Getting ready to do my 70 LT-1

      Comment

      • Dennis H.
        Expired
        • September 30, 2005
        • 226

        #4
        Re: What is the Rear Main Seal of choice today?

        Thanks found the GM
        10121044 seal.

        Also read
        Harry Sadlock thread titled rear main seal and there is some conflicting information in it;

        https://www.forums.ncrs.org/showthre...rear+main+seal

        In post #8 Edward Dupere said he agreed with Mark to use usePermatex anaerobic sealant #51813 but later in the same paragraph said don'tput any sealant on the ends of the new seal, they are already pretreated withan adhesive and will bond together when the lower bearing cap is installed.

        ????????????????????

        Comment

        • Mark E.
          Extremely Frequent Poster
          • April 1, 1993
          • 4537

          #5
          Re: What is the Rear Main Seal of choice today?

          Not really conflicting. Use the sealant on the surfaces shown but keep it away from the seal ends (or any part of the seal).
          Mark Edmondson
          Dallas, Texas
          Texas Chapter

          1970 Coupe, Donnybrooke Green, Light Saddle LS5 M20 A31 C60 G81 N37 N40 UA6 U79
          1993 Coupe, 40th Anniversary, 6-speed, PEG 1, FX3, CD, Bronze Top

          Comment

          • Thomas N.
            Very Frequent User
            • July 31, 2002
            • 397

            #6
            Re: What is the Rear Main Seal of choice today?

            I like the GST rear main seals. It is one piece. You cut it, slide it over the crank, and the one cut is on the top, and is a continuous seal at the cap to block interface. Higher quality materials also. Made in the UK, but have US distributors.
            NCRS New England Chapter Chairman 2022, 2024
            N E Regional Chairman 2024
            1967 Corvette Convertible Under Restoration
            1996 Corvette Coupe NCRS Chapter Top Flight 99.5, NCRS National Top Flight 100.0

            Comment

            • Dennis H.
              Expired
              • September 30, 2005
              • 226

              #7
              Re: What is the Rear Main Seal of choice today?

              Have not heard of a GST one piece rear seal for a Gen 1 block but found a link.

              Comment

              • William F.
                Extremely Frequent Poster
                • June 9, 2009
                • 1363

                #8
                Re: What is the Rear Main Seal of choice today?

                Aren't 'surfaces shown" the place where seal comes with its own sealant??

                Comment

                • Mark E.
                  Extremely Frequent Poster
                  • April 1, 1993
                  • 4537

                  #9
                  Re: What is the Rear Main Seal of choice today?

                  Originally posted by William Ford (50517)
                  Aren't 'surfaces shown" the place where seal comes with its own sealant??

                  I think I understand the confusion. Place the sealant on the shaded area but away from the lip that makes contact with the crank (that's what I meant by "seal end". This is for a "dry seal"; I've never used a seal with sealant pre-applied. Maybe someone can comment on that.
                  Mark Edmondson
                  Dallas, Texas
                  Texas Chapter

                  1970 Coupe, Donnybrooke Green, Light Saddle LS5 M20 A31 C60 G81 N37 N40 UA6 U79
                  1993 Coupe, 40th Anniversary, 6-speed, PEG 1, FX3, CD, Bronze Top

                  Comment

                  • Frank H.
                    Expired
                    • November 17, 2017
                    • 44

                    #10
                    Re: What is the Rear Main Seal of choice today?

                    i really like the idea, have you or do you know anyone who's tried it?
                    Originally posted by Thomas Nowak (10784)
                    I like the GST rear main seals. It is one piece. You cut it, slide it over the crank, and the one cut is on the top, and is a continuous seal at the cap to block interface. Higher quality materials also. Made in the UK, but have US distributors.

                    Comment

                    • Thomas N.
                      Very Frequent User
                      • July 31, 2002
                      • 397

                      #11
                      Re: What is the Rear Main Seal of choice today?

                      I've used these. I've got a bbc sitting in my chassis now with that seal. With a two piece seal you have two potential leak points. With this seal you have one leak point, and the potential leak point is up high.
                      NCRS New England Chapter Chairman 2022, 2024
                      N E Regional Chairman 2024
                      1967 Corvette Convertible Under Restoration
                      1996 Corvette Coupe NCRS Chapter Top Flight 99.5, NCRS National Top Flight 100.0

                      Comment

                      • Mark E.
                        Extremely Frequent Poster
                        • April 1, 1993
                        • 4537

                        #12
                        Re: What is the Rear Main Seal of choice today?

                        Originally posted by Dennis Hendrix (44677)
                        Have not heard of a GST one piece rear seal for a Gen 1 block but found a link.

                        https://hotrodenginetech.com/one-pie...-block-chevys/

                        Sounds interesting but I can't visualize how it's installed. It's a complete ring that's cut once. Then is it inserted into the crank side with the cut facing the top of the block? Then how is the cap installed?
                        Mark Edmondson
                        Dallas, Texas
                        Texas Chapter

                        1970 Coupe, Donnybrooke Green, Light Saddle LS5 M20 A31 C60 G81 N37 N40 UA6 U79
                        1993 Coupe, 40th Anniversary, 6-speed, PEG 1, FX3, CD, Bronze Top

                        Comment

                        • Thomas N.
                          Very Frequent User
                          • July 31, 2002
                          • 397

                          #13
                          Re: What is the Rear Main Seal of choice today?

                          Pretty simple.
                          1) Cut the seal at the area called out in the instructions.
                          2) Place the seal over the respective journal of the crank, with the inside facing the inside of the engine.
                          3) If you are building a new motor and your engine is upside down, have the cut facing upward.
                          4) Install the crank and the seal combination in the engine with the seal going into the groove that is is designed to go in (same as the upper half of a normal seal). The reason that the seal is facing upwards, when you are installing the seal into the groove, and you a wielding the crank and seal together, there is no edges to catch.
                          5) Roll the seal 180 degrees so the slot is facing downward (If your engine is upside down). When you flip the engine, the slot will be facing up at 12:00 looking at the rear of the engine.
                          6) Install the main caps (again the seal fits in the groove of the main seal) and torque away.
                          NCRS New England Chapter Chairman 2022, 2024
                          N E Regional Chairman 2024
                          1967 Corvette Convertible Under Restoration
                          1996 Corvette Coupe NCRS Chapter Top Flight 99.5, NCRS National Top Flight 100.0

                          Comment

                          • Frank H.
                            Expired
                            • November 17, 2017
                            • 44

                            #14
                            Re: What is the Rear Main Seal of choice today?

                            Originally posted by Thomas Nowak (10784)
                            I've used these. I've got a bbc sitting in my chassis now with that seal. With a two piece seal you have two potential leak points. With this seal you have one leak point, and the potential leak point is up high.
                            thomas, that's great info. can these be installed with the crank in the block and the block in the car? in other words, just like doing a 2 piece seal in the car? also, i noticed in the link that " pricing is batch quantity related", wonder if it's possible to buy singles?

                            Comment

                            • Mark E.
                              Extremely Frequent Poster
                              • April 1, 1993
                              • 4537

                              #15
                              Re: What is the Rear Main Seal of choice today?

                              Originally posted by Thomas Nowak (10784)
                              Pretty simple.
                              1) Cut the seal at the area called out in the instructions.
                              2) Place the seal over the respective journal of the crank, with the inside facing the inside of the engine.
                              3) If you are building a new motor and your engine is upside down, have the cut facing upward.
                              4) Install the crank and the seal combination in the engine with the seal going into the groove that is is designed to go in (same as the upper half of a normal seal). The reason that the seal is facing upwards, when you are installing the seal into the groove, and you a wielding the crank and seal together, there is no edges to catch.
                              5) Roll the seal 180 degrees so the slot is facing downward (If your engine is upside down). When you flip the engine, the slot will be facing up at 12:00 looking at the rear of the engine.
                              6) Install the main caps (again the seal fits in the groove of the main seal) and torque away.
                              So the crank has to be removed? What about a normal seal R&R with the engine in the car?
                              Mark Edmondson
                              Dallas, Texas
                              Texas Chapter

                              1970 Coupe, Donnybrooke Green, Light Saddle LS5 M20 A31 C60 G81 N37 N40 UA6 U79
                              1993 Coupe, 40th Anniversary, 6-speed, PEG 1, FX3, CD, Bronze Top

                              Comment

                              Working...
                              Searching...Please wait.
                              An unexpected error was returned: 'Your submission could not be processed because you have logged in since the previous page was loaded.

                              Please push the back button and reload the previous window.'
                              An unexpected error was returned: 'Your submission could not be processed because the token has expired.

                              Please push the back button and reload the previous window.'
                              An internal error has occurred and the module cannot be displayed.
                              There are no results that meet this criteria.
                              Search Result for "|||"