Skip to content
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
Skins
  • Light
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (Slate)
  • No Skin
Collapse
Brand Logo

DT125R FORUM

  1. Home
  2. Technical Zone
  3. Engine
  4. Power valve o rings?

Power valve o rings?

Scheduled Pinned Locked Moved Engine
23 Posts 3 Posters 1.6k Views
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • CalumC Offline
    CalumC Offline
    Calum
    wrote on last edited by
    #6

    No 19 are the seals. They sit in the bushes.

    Always Originate, Never Pirate!

    1 Reply Last reply
    0
    • S Offline
      S Offline
      SpookDog
      wrote on last edited by
      #7

      The kickstart side is straightforward, simple groove that fits perfectly. It’s the gearchange side that has no groove or place for a seal. The previous owner had the orange one just flopping around and a black smaller o ring squashed flat between the bush and the cover. Neither of those two are affecting a seal. I’ll check and see if there’s a paper gasket for that side. That would be enough of a seal...
      It’s frustrating when the last owner didn’t know what they were doing, it makes reassembly a bear!...

      1 Reply Last reply
      0
      • CalumC Offline
        CalumC Offline
        Calum
        wrote on last edited by
        #8

        The pictures are a give away.

        The bush there has a groove cut out of it, the O-Ring sits inside the groove, the bush secures to powervalve in place.

        Always Originate, Never Pirate!

        1 Reply Last reply
        0
        • S Offline
          S Offline
          SpookDog
          wrote on last edited by
          #9

          Sorry bud? Pics? I get a link with ‘all text’ access denied.
          Neither my bush or the cover have oring grooves on them, on that side. I wish I could post pics to show you what I mean but I just have a phone.

          1 Reply Last reply
          0
          • CalumC Offline
            CalumC Offline
            Calum
            wrote on last edited by
            #10

            @SpookDog Oh Yeah 🤣 How annoying.

            Sorry, it looks like they are blocking that resource.

            It's a parts diagram showing you where the O-Rings go.

            https://www.fowlersparts.co.uk/main/img/assemblies/large/e2bbdd33f448b949dadded717beb407f.png?6

            I'll get it hosted elsewhere and link it in.

            Always Originate, Never Pirate!

            1 Reply Last reply
            0
            • S Offline
              S Offline
              SpookDog
              wrote on last edited by
              #11

              Fowler’s don’t like hotlinking apparently!😊
              I found the diagram, unfortunately it is different from what I have fitted. I found I can affect a seal if I slip the oring over the end cap. Without it the whole cap/bush is very loose. It slops around loads! Whereas the other side is a good fit.
              I wasn’t even sure if it was original to the barrel. Who knows what butchery was done before. The PV has 3bn on it I think, yet the barrel is 3mb. I don’t know if there’s a difference. I’m still fumbling around in the dark. The only other 2strokes I’ve worked on were air cooled, ts er’s, and more shedloads of Vespa & Lambretta’s than I can recall. I don’t recall them having an oring between them 🙂
              Cheers bud!

              1 Reply Last reply
              0
              • CalumC Offline
                CalumC Offline
                Calum
                wrote on last edited by
                #12

                The bushes wear out.

                There were different types of powervalves, not sure how they differed on the bush side of things though.

                Always Originate, Never Pirate!

                1 Reply Last reply
                0
                • S Offline
                  S Offline
                  SpookDog
                  wrote on last edited by
                  #13

                  One more question! Do you know what the black oring is for? I’ve got a full gasket set with black oring, but the only black oring I found was squashed into the PV and is obviously not right.
                  It’s about 3/4 inch.

                  1 Reply Last reply
                  0
                  • S Offline
                    S Offline
                    SpookDog
                    wrote on last edited by
                    #14

                    Sorry, was busy thumb typing on a tiny screen!🤪
                    It’s not just the bush, the end cap it fits into also seems small. Plus it’s fixed, doesn’t move...
                    I’m guessing that the 3mb was a later servo operated valve? Totally different end cap on that side?...

                    CalumC 1 Reply Last reply
                    0
                    • S SpookDog

                      Sorry, was busy thumb typing on a tiny screen!🤪
                      It’s not just the bush, the end cap it fits into also seems small. Plus it’s fixed, doesn’t move...
                      I’m guessing that the 3mb was a later servo operated valve? Totally different end cap on that side?...

                      CalumC Offline
                      CalumC Offline
                      Calum
                      wrote on last edited by
                      #15

                      @SpookDog the markings on the powervalve are misleading. I can't remember what is on the 3mb barrel. I do know that the two barrels take different valves, but I don't think the codes are representative.

                      Always Originate, Never Pirate!

                      1 Reply Last reply
                      0
                      • NottsbikerN Offline
                        NottsbikerN Offline
                        Nottsbiker
                        wrote on last edited by
                        #16

                        Dont do what I did when I was being stupid and try and fit the o-rings onto the power valve itself lol

                        They go into the end caps and there is also an orange seal for the pulley end as well

                        I also got a black o-ring in my Athena gasket kit from PJME and have no idea where it goes

                        Wish it was the thermostat one as I need one but its the wrong size

                        1 Reply Last reply
                        0
                        • CalumC Offline
                          CalumC Offline
                          Calum
                          wrote on last edited by
                          #17

                          Thermostat is paper gasket IIRC. Kellogs Cereal will do.

                          Always Originate, Never Pirate!

                          NottsbikerN 1 Reply Last reply
                          0
                          • S Offline
                            S Offline
                            SpookDog
                            wrote on last edited by
                            #18

                            Same as in my gasket set, it’s to small. You need a 33mm one for the thermostat. Get one from eBay. If you don’t have an account someone here will probably order it for you. It’ll be pennies ...

                            1 Reply Last reply
                            0
                            • S Offline
                              S Offline
                              SpookDog
                              wrote on last edited by
                              #19

                              Sorry it’s 27mm Inner Diametre X 2.5 or 3mm Cross Section.

                              Calum, cheers for the info bud, it puts my mind to rest. I always worry more when learning a new engine...

                              1 Reply Last reply
                              0
                              • CalumC Calum

                                Thermostat is paper gasket IIRC. Kellogs Cereal will do.

                                NottsbikerN Offline
                                NottsbikerN Offline
                                Nottsbiker
                                wrote on last edited by
                                #20

                                @Calum there is an o-ring under the thermostat itself with the gasket above that

                                1 Reply Last reply
                                0
                                • S Offline
                                  S Offline
                                  SpookDog
                                  wrote on last edited by
                                  #21

                                  The small oring in the gasket set is for the metal coolant pipe. It goes on the end that mates to the pump. Mysteries solved!...

                                  1 Reply Last reply
                                  1
                                  • CalumC Offline
                                    CalumC Offline
                                    Calum
                                    wrote on last edited by
                                    #22

                                    Hhmm, yeah it's been such a long time since I've worked on that engine

                                    Always Originate, Never Pirate!

                                    1 Reply Last reply
                                    0
                                    • S Offline
                                      S Offline
                                      SpookDog
                                      wrote on last edited by
                                      #23

                                      Hey! You weren’t wrong, there is a paper gasket. I was wrong about the oring though. It’s to big for the coolant pipe🙄

                                      1 Reply Last reply
                                      0
                                      Reply
                                      • Reply as topic
                                      Log in to reply
                                      • Oldest to Newest
                                      • Newest to Oldest
                                      • Most Votes


                                      • Login

                                      • Don't have an account? Register

                                      • Login or register to search.
                                      • First post
                                        Last post
                                      0
                                      • Recent
                                      • Tags
                                      • Popular
                                      • Users
                                      • Groups