Announcement

Collapse
No announcement yet.

28mm Drain "Plug" on H-series Motors

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    28mm Drain "Plug" on H-series Motors

    Wow, it has been a while since I have posted on here! I am getting the car freshened up for the June 28th Laguna Seca track day, and I found something I wanted to share with all of you, and ask a question:

    So, for those who are interested in using this K-tuned oil pressure sensor adapter between the block and the oil pressure switch in its stock location, don't.



    Here is why: the stock drain "plug", as I guess it is called, which is the 28mm massive bolt with a 1/8" BSPT center thread for the oil pressure switch, pictured below:


    Does not have a flush surface at all, but rather a relief in the center and a raised perimeter. Since the K-tuned unit is expecting a flush surface to mate with, as in the stock K-series oil sending unit location, you can tighten it all you want, you will just end up spinning off three layers of BSPT threads in this 28mm bolt, as the jam nut is too wide to fit into the relief. It frustrates me that H guys on YT say the unit fits perfectly.

    This is exactly what happened to me, and it was, of course, leaking quite a bit. So, I have a damaged 28mm drain "plug" and I need to source a new one. My question is this: you go on Majestic and see this chart:

    Pick #32, which is still for sale, but it is called "Bolt, Drain Plug". Cross referencing an OBD-1 and OBD-2 H series, it is the same part number:
    90001-PM3-003
    Can anyone verify that this is the same part in the second picture above? The reason I quote "plug" is because it doesn't seem like much of a plug to me, but maybe I am misunderstanding something.
    *** Think of others before thinking of yourself. ***
    ********** Spread love, not hate. ***********
    ****Lift others up with kind and helpful words****

    F20A_CB7, I miss you, but I will see you one day.
    "Nothing a little prayer can't fix."


    MRT
    Selling on Ebay!

    15.10 @ 90.42mph
    The quest for 9s ceased, now the goal is a circuit track monster!
    Current fastest Laguna Seca Lap: 1:52.889

    #2
    32 is the oversized coolant plug. In your diagram, it looks like #2 would be the bushing/adapter, as it has the oil sensor (#31) and the small wire connector screw for it (#33) are lined up with it. Although when I follow through to the Majestic site via your link, I am getting a different diagram where #2 is no longer pictured, so I can't find the part number for you...



    - 1993 Accord LX - White sedan (sold)
    - 1993 Accord EX - White sedan (wrecked)
    - 1991 Accord EX - White sedan (sold)
    - 1990 Accord EX - Grey sedan (sold)
    - 1993 Accord EX - White sedan (sold)
    - 1992 Accord EX - White coupe (sold)
    - 1993 Accord EX - Grey coupe (stolen)
    - 1993 Accord SE - Gold coupe (sold)
    Current cars:
    - 2005 Subaru Legacy GT Wagon - Daily driver
    - 2004 Chevrolet Express AWD - Camper conversion

    Comment


      #3
      Yep, you are right, it is #2, hold on and let me get that link and part number.
      *** Think of others before thinking of yourself. ***
      ********** Spread love, not hate. ***********
      ****Lift others up with kind and helpful words****

      F20A_CB7, I miss you, but I will see you one day.
      "Nothing a little prayer can't fix."


      MRT
      Selling on Ebay!

      15.10 @ 90.42mph
      The quest for 9s ceased, now the goal is a circuit track monster!
      Current fastest Laguna Seca Lap: 1:52.889

      Comment


        #4
        Here is the link to the cylinder block - oil pan page for a '98 Prelude SH (same year as my JDM H23A).

        https://www.hondaautomotiveparts.com...-block-oil-pan

        No hyperlinks for 51, 2, 30, or 31

        Makes me think they may be in another menu for the car, trying to look now.

        *** Think of others before thinking of yourself. ***
        ********** Spread love, not hate. ***********
        ****Lift others up with kind and helpful words****

        F20A_CB7, I miss you, but I will see you one day.
        "Nothing a little prayer can't fix."


        MRT
        Selling on Ebay!

        15.10 @ 90.42mph
        The quest for 9s ceased, now the goal is a circuit track monster!
        Current fastest Laguna Seca Lap: 1:52.889

        Comment


          #5
          Originally posted by af_1132 View Post
          Makes me think they may be in another menu for the car, trying to look now.
          If by another menu you mean a junkyard, yep I bet that's where you'll find it! Or I bet there must be somebody with a dead block out there who would be willing to pull that for you. Good luck!


          - 1993 Accord LX - White sedan (sold)
          - 1993 Accord EX - White sedan (wrecked)
          - 1991 Accord EX - White sedan (sold)
          - 1990 Accord EX - Grey sedan (sold)
          - 1993 Accord EX - White sedan (sold)
          - 1992 Accord EX - White coupe (sold)
          - 1993 Accord EX - Grey coupe (stolen)
          - 1993 Accord SE - Gold coupe (sold)
          Current cars:
          - 2005 Subaru Legacy GT Wagon - Daily driver
          - 2004 Chevrolet Express AWD - Camper conversion

          Comment


            #6
            Wish I had this part for ya, but i don't... not seeing it on ebay etc either
            Last edited by Raf99; 06-24-2021, 08:37 AM.

            Comment


              #7
              It's okay guys, I appreciate the help. I just wish it didn't have a stupid lip on it. It just doesn't seem necessary to me. I was successful in using a dremel last night to smooth out the damaged threads and have plenty left to send the K-tuned adapter, sans jam nut, all the way to the bottom. I'll just use gasket maker to seal, which is what you find in there when you remove the stock pressure switch.
              *** Think of others before thinking of yourself. ***
              ********** Spread love, not hate. ***********
              ****Lift others up with kind and helpful words****

              F20A_CB7, I miss you, but I will see you one day.
              "Nothing a little prayer can't fix."


              MRT
              Selling on Ebay!

              15.10 @ 90.42mph
              The quest for 9s ceased, now the goal is a circuit track monster!
              Current fastest Laguna Seca Lap: 1:52.889

              Comment

              Working...
              X