Announcement

Collapse
No announcement yet.

carb issues maybe?

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

    carb issues maybe?

    i just bought a 80 gs850G monday and havnt ridden it yet...but have let it idle in the garage.

    first off, the first time i went to check the bike out, it would barely run. it backfired very badly and wouldnt rev up smooth at all until about 4K rpm.

    second time i checked the bike out, they said they took it up and down the street a little bit and it was idling decently and would rev up OK, not perfectly but a ton better than before, from idle.

    so now i have it at home and still havnt ridden it on the street but when its idling it will sometimes miss out if ur giving it past 1/2 throttle from idle.

    i havent really done much work to it yet. but i did notice after it had been runnin for a while... that the cyl head fins farthest to the right side of the bank (im assuming #4?) were touchable...pretty warm but touchable.
    but...the cyl farthest to the left (#1?) was burning hot.

    im assuming its gettin a lean mix through that carb.
    my friends are tellin me just to run it and 'knock the cobwebs outa it' to clean it out...but if its gettin too hot in there from being too lean, it can cause damage like detonation and stuff like that.

    what do u guys think? does it sound like im due for a carb rebuild?


    ps, my exhaust pipe on the left side has more fluctuation in it than my right side...kinda tellin me its a prob with one of the left 2 cyls'

    thanks
    brad

    #2
    If the fins are cool enough to touch after it's been running for 5 minutes or so, odds are that cylinder isn't firing. It's normal for these engines to get very hot.

    Wait till that 95 degree day after running 90 m.p.h. into headwinds for three hours...

    Comment


      #3
      I had a problem (similar to yours) recently that directed me to cleaning the carbs... twice. After all of that I checked my coils and plug wires in my garage with the tank off, the vacuum line plugged and the lights out and what do you know, one of my plug wires was arcing to the frame and then when I tried moving the offending wire away from the frame further it literally crumbled and fell out. By the way these were aftermarket coils and wires that were installed 19 years ago. New coils and wires... problem solved. My point is that sometimes ignition problems sometimes resemble dirty carbs. Check your wires carefully before yanking the carbs just for assurance.

      Comment


        #4
        thanks for the info guys
        i'll have a look at the ignition system before i go pullin carbs off now!

        a cool trick i once learned to check for an arcing wire, is to spray it with glass cleaner while running....if its gona arc it will for sure then cuz all the mist and u can hear the spark then, and the motor die off when its doing it...so it looks like thats what im gona be doin tomorrow night

        thanks again for the info, its much appreciated!

        cya
        brad

        Comment


          #5
          well i replaced both coils w/ wires...and put some new plugs in there, and its still acting the same.

          i emptied the tank and have fresh fuel in it now...maybe just running it a while will get some stuff outa the carbs that might be there.

          any more ideas short of a carb rebuild?


          thanks guys
          cya
          brad

          Comment


            #6
            Cleaning them's a good start. Blast out the jets with an air compressor. If that doesn't work I've found that paper clips works pretty swell for getting soild junk out of fuel jets. Just take care not to scratch them. Make sure you check the air jets too. You want to clean them right the first time to avoid pulling them off and taking them apart again.

            Comment


              #7
              i was doin some readin on the old q&a's and saw a lot of talk about pipes and air filters requiring rejetting.

              the exhaust pips on my bike dont look the stock length. i've seen soem pics of gs850's and the pipes come out pretty long, but on my bike they stop right about the center of the rear wheel. they are pretty loud too.

              could the fact that they are aftermarket pipes (if they are im assuming) cause it to be running too lean and making it run rougher?

              im still gettin some backfiring out of the pipes if i totally open the choke. i have to use the choke to rev up past 3500 ish rpms...which is tellin me its runnin pretty lean.

              any advice or coments?
              as always, thanks!

              cya
              brad

              Comment


                #8
                I had a similar problem this weekend. We put new carb kits in a 1980 850 and it started fine and idled, but I couldn't get it to rev over 4000 rpm. The plugs looked fine. So we pulled the carbs again, and the intake boots #1 and #2 fell apart. Getting some new ones soon. Orings looked like they were barely sealing, there was some residue on the engine side of all the boots. All I can think of was there was a major air leak I coulnd't see.

                Find out in a few weeks... 8)

                Comment


                  #9
                  I have been in the middle of getting my carbs all sorted out on my 850 over the last year. (It's been an off & on labor--mostly off as I also changed jobs and locations then.)

                  Let me second what some of the other posts have indicated by adding that I have replaced the intake boots and o-rings, as well as the boots on the other side between the air intake and carbs. This after going through the carbs a number of times to clean and adjusts the floats. Also, I've replaced all the o-rings in the carbs.

                  I've learned that when testing the carbs and any adjustments made, you need to attach the air box as without it you will get an improper mixture and firing.

                  Also, if at all possible, I recommend that you avoid messing with the pilot/mixture screws. Usually they are seized and can strip. I practically ruined one carb trying to remove one pilot screw, requiring me to buy a used carb log. In the replacement carb log, I found that only one pilot screw would move at all, so I've left them alone.

                  I guess I'm just saying that there are a number of issues and elements to keep in mind, and if it takes longer that you want, take heart--you're not alone.

                  Good luck, and hopefully things will iron out quicker for you.

                  Comment


                    #10
                    thanks for the heads up on those screws, if i get that far i'll be careful

                    i'll have to check my intake boots too...see if theya re torn or anything.

                    later
                    brad

                    Comment


                      #11
                      Some things to look for, or that you might see:

                      On the intake boots, mine were beginning to separate from the metal flange, so I replaced them. If you do too, be aware that the screws holding them in may be inclined to strip out their phillips' heads. I had to hacksaw slots into mine. Then I replaced them with a standard 10 mm hex head. Others opt for allen heads.

                      On the other boots (the suzuki dealership called them "rubber hoses") between the carbs and the airbox, I had two that were hardened on the botton half, while the other two were beginning to harden on the bottom. In any case, a good seal was impossible.

                      I know it amounts to some more expenses (maybe as much as $120--I think the intake boots were $20 each and the hoses $10 each), but it may make the difference you need.

                      On the pilot screws, the only reason you will want/need to get them out is in order to get to the small o-ring below them. And the only reason to have to get that o-ring out, that I can think of, is if you want to completely dip and soak the carbs. I'd like to think that a few cans of carb cleaner, new o-rings elswhere, and a good cleaning everywhere else should be fine, thereby negating having to get those pilot screws out. You should not/may not have to take the carbs apart. But you may need to take them off the engine.

                      Just some thoughts, which are open to any corrections too. Good luck, and as Uncle Red says, "I'm pullin' for you. We're all in this together."

                      Comment


                        #12
                        thanks again for teh advice! and go figure, u were right about my carb rubber boots. the 4 that go from the air box to the carbs were all dry and pulled away from the carbs squearely. 1 was just flat out off the carb all together.
                        i sprayed some carb cleaner with it runnin around the boots from the carb to the intake and it didnt affect it any, so im not gona go there yet. but when i tried around the air box side of it, it chuggled and died quickly.

                        hopefully thats my only problem and the carbs inside are ready to rock and roll. i'm gona order some of those boots and i'll let u guys know what happens after that.


                        once again, THANKS A LOT FOR UR HELP!!!

                        cya
                        brad

                        Comment


                          #13
                          Hi Hustler,
                          First of all congrats on the new-to-you bike.
                          You might want to look inside your aibox. The side covers are supposed to have a foam seal around the edge. I found that mine had turned into a sticky gook - the foam cushion seal being completely disintigrated. There is also a seal around the top circumference of the air filter element - that was goo too. I followed the advice of others on this site to replace it with foam cut from a mouse pad. I used super glue to attach it -- worked great.
                          I have gone through two of the carbs dipping and was surprised that they were pretty clean inside with no blocked orifices found and air screws came out easily.
                          Having a really tough time with the intake boots on the inside cylinders though, using PB blaster and an impact driver and two of the boot bolts haven't budged. :x I am afraid to hit it too hard for fear of cracking the cylinder head! I found that the old o rings on the boots I took off were flat as pancakes and hard as rock. I suspect the intake o rings were the main culpris in my stalling and idling problems.

                          Comment


                            #14
                            i'll have to have a look at that too. thanks for the insight. and i hope ur bolts let up soon on ur head. maybe u should try another type of rust penetrator??


                            cya
                            brad

                            Comment


                              #15
                              Originally posted by hustler
                              i'll have to have a look at that too. thanks for the insight. and i hope ur bolts let up soon on ur head. maybe u should try another type of rust penetrator??


                              cya
                              brad
                              Thanks for the moral support. I did get the boots off last night but stripped the head on one of the phillips head bolts. Ipact driver was the most useful tool I ever bought. Will see if I can get some metric allen heads to replace them. Next on the list -- valve clearances, then check the charging system.

                              Comment

                              Working...
                              X