Announcement

Collapse
No announcement yet.

No vacuum

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

    No vacuum

    Hi there guys and gals. Need some help. I recently cleaned and resealed my bs34 carbs. They're on an 81 gs400x . It's a Canadian / Euro bike. I don't seem to be getting any vacuum from the vacuum port. If I manually suck on the hose I get fuel from the petcock if not I get nothing. Any ideas?

    #2
    is this a vacuum petcock?
    Check your hoses
    and yes the hoses can age and collapse internally.
    1983 GS 550 LD
    2009 BMW K1300s

    Comment


      #3
      oh and no vacuum? man that sucks!
      1983 GS 550 LD
      2009 BMW K1300s

      Comment


        #4
        Got it on the right nipple?? Brass nipple at the rear of carb 2 ?? Place your hand over the face of carb 2 and crank the engine...does it make suction on your hand??? If not theres a problem with the cylinder..otherwise you should feel the in take suction on your hand.

        Was the bike running before this clean up??? The more details you provide the better the answers youll get.
        MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
        1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

        NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


        I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

        Comment


          #5
          if sucking on the hose gives gas, and stop sucking cuts gas off, i'd say
          it's a vacuum petcock and it seems to work.
          Hose seems fine, too.

          Seems to be an issue with the carbs, maybe the vacuum hose on the wrong carb ?

          If set to pri, does the bike run ?
          If yes check if one of the other hoses sucks air.
          Can't be more specific, i do not know which carb the vacuum hose should
          be connected to on a gsx400 but there are people here with way more
          knowledge of that bike than me...


          edit : Chuck posted just before me .. did not see it until after i posted
          Last edited by Rijko; 04-29-2017, 07:45 PM.
          Rijk

          Top 10 Newbie Mistakes thread

          CV Carb rebuild tutorial
          VM Carb rebuild tutorial
          Bikecliff's website
          The Stator Papers

          "The thing about freedom - it's never free"

          Comment


            #6
            Thanks everyone. Very new to bikes. Had it hooked up to the wrong nipple. Now thats working onto the next issue. It starts on choke runs for a 30 secs and dies. If I try to give it any throttle it dies right away. It wasn't running when I bought it. I pulled the carbs and petcock and used my ultrasonic to clean them afterm I pulled them apart. Put all new orings in and put them back together. Sorry for the lack of info last time.

            Comment


              #7
              airbox on>?
              1983 GS 550 LD
              2009 BMW K1300s

              Comment


                #8
                No airbox came with pods

                Comment


                  #9
                  Sorry and they weren't on

                  Comment


                    #10
                    review this rebuild tutorial and see what / if you missed anything.



                    Store this for future use and for service manuals etc etc.


                    MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
                    1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

                    NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


                    I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

                    Comment


                      #11
                      assuming it was jetted and running fine pre storage
                      then the pods however non restritive they are should be on
                      otherwise your lean
                      1983 GS 550 LD
                      2009 BMW K1300s

                      Comment


                        #12
                        Originally posted by Cipher View Post
                        assuming it was jetted
                        yep, i'd take off the carbs and check jet sizes to be sure.
                        They should be bigger than standard.
                        Rijk

                        Top 10 Newbie Mistakes thread

                        CV Carb rebuild tutorial
                        VM Carb rebuild tutorial
                        Bikecliff's website
                        The Stator Papers

                        "The thing about freedom - it's never free"

                        Comment


                          #13
                          It should at least start and idle without the pods..but trying to run it up will make it die. Put the pods on a see what it does then. If it will idle and still die then cut up some old socks and slip a sleeve over each pod to richen it up. If this solves the problem youll need to rejet up on the main jets. I would go up two sizes above whats in the now for my starting point..if the added restriction makes it better that is.

                          another way to see if its too lean ( with the pods on ) is to apply about 1/4 choke and then try running it up. The choke will richen the mix a bit. If it doesnt solve the problem, or makes it worse, then your too rich already and will be going down in jet sizes.

                          Also at the top of the carb forum is a STICKY about CV carb tuning proceedures...see that read also.
                          MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
                          1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

                          NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


                          I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

                          Comment


                            #14
                            They were hard to read. But it should run even if not jetted right? Have ordered some bigger ones overstock numbers so I can tune it once it's running.

                            Comment


                              #15
                              CV carbs will IDLE without an airbox or pods...not rev up though. The CVs need some restriction form the airbox or pods to work right. Thats why i just typed all the quicky ways to do a crude symptom diagnostics in my previous post.
                              MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
                              1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

                              NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


                              I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

                              Comment

                              Working...
                              X