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  • #16
    Cotten, it’s always good to ask as a reminder, thanks!

    I’ve always thought the weak link was the gasket between the manifold and carburetor, it’s a pretty chubby gasket but the screws don’t bite very deep into the brass carburetor!

    BTW, the non-Liberty float was rubbing on the bowl, probably from swelling, so I merely tweaked it sideways. The level was good (...and still good today).
    Last edited by pisten-bully; 07-12-2020, 08:04 PM.
    Pisten Bully is Harry Roberts in Vermont.

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    • #17
      Originally posted by pisten-bully View Post
      Cotten, it’s always good to ask as a reminder, thanks!

      I’ve always thought the weak link was the gasket between the manifold and carburetor, it’s a pretty chubby gasket but the screws don’t bite very deep into the brass carburetor!

      BTW, the non-Liberty float was rubbing on the bowl, probably from swelling, so I merely tweaked it sideways. The level was good (...and still good today).
      Personally, Harry,..

      I think 'chubby' can be a problem: The more squish, the more the flanges can distort. (So I commissioned skinny ones...)
      Since this interface cannot be bubble-tested, we must arbitrarily grind the manifold's flange to flat for inspection,
      and lathe-cut the carb flange to flat.

      99.9% need it.
      Then a torque to 10, no more than 13 ft-lbs should do it; But if problems persist, a test at idle with an un-lit propane torch can display an issue, although it cannot discern between the flanges and the throttle bushings.

      Do you think the float will stop swelling?
      'Spose it could. Its about the gas and not the float.

      ...Cotten
      PS: Note in the attachment how the region of the flange adjacent to the casting-stiffening gallery holds it from being 'pulled' by the fastener stress.
      Attached Files
      Last edited by T. Cotten; 07-13-2020, 12:22 PM.
      AMCA #776
      Dumpster Diver's Motto: Seek,... and Ye Shall Find!

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      • #18
        New condensers are cheaply made (yes even NAPA I've cut them open) and aren't made to withstand the vibration on our bikes. I'd try changing it for sure especially since you've been over everything else and know your bike well.
        I know I'm not the only one who went about troubleshooting everything else bypassing a bad condenser because it was "new".
        Jason Zerbini
        #21594
        Near Pittsburgh PA (Farm Country)
        Allegheny Mountain Chapter http://amcaamc.com/

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        • #19
          Thanks Jason, you and Dave have the same idea! I only hesitated on replacing the condenser because I think a bad condenser will give you burnt points, and my points are fine. But I've got one and if it ever stops raining here I'll give it a shot!
          Pisten Bully is Harry Roberts in Vermont.

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          • #20
            Harry,

            I was on a cross country trip from NJ to CA. I decided to tune up my bike in CA, only made it 100 miles before the new condenser took a Sh^%$t. Installed the old one and rode all the way back to NJ. Jason is right, new ones are junk. I installed Clyde Crouch's electronic ignition after that trip in 1996 and have never had another ignition problem.

            Dave

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            • #21
              I had forgotten about this discussion here: https://forum.antiquemotorcycle.org/...ight=Condenser where Jason installed a capacitor in lieu of a condenser, so I’m going to try the same!
              Pisten Bully is Harry Roberts in Vermont.

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              • #22
                My chief overfills the reserve tank with oil. There must be a small seep at the top idk. What I am saying is that oil will cause it to misfire without fouling the plugs.

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                • #23
                  Originally posted by Arley View Post
                  My chief overfills the reserve tank with oil. There must be a small seep at the top idk. What I am saying is that oil will cause it to misfire without fouling the plugs.
                  Thanks Arley, I'll look at that, too!

                  But this afternoon I determined my multimeter was giving me the same intermittent problems when checking resistance, so I went to our warehouse and picked up my newer and better one and I may have found something! The through post in the distributor that feeds the points on the inside, and receives 12V from the coil and has the condenser attached to it on the outside goes through the distributor body with two insulating washers, one inside and one outside. The outside one was half gone... so maybe, just maybe the post was intermittently grounding out on the distributor base. We'll see!

                  Pisten Bully is Harry Roberts in Vermont.

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                  • #24
                    Originally posted by pisten-bully View Post
                    Thanks Arley, I'll look at that, too!

                    But this afternoon I determined my multimeter was giving me the same intermittent problems when checking resistance, so I went to our warehouse and picked up my newer and better one and I may have found something! The through post in the distributor that feeds the points on the inside, and receives 12V from the coil and has the condenser attached to it on the outside goes through the distributor body with two insulating washers, one inside and one outside. The outside one was half gone... so maybe, just maybe the post was intermittently grounding out on the distributor base. We'll see!

                    May be it, probably is. Was the the bolt loose? I ask because when they short out it is either on or off.

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                    • #25
                      I think Kiwi sells an improved insulator for this.

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                      • #26
                        Originally posted by Arley View Post
                        My chief overfills the reserve tank with oil. There must be a small seep at the top idk. What I am saying is that oil will cause it to misfire without fouling the plugs.
                        If you have oil in the gas ,you have gas in the oil and you need tank repair or you will be rebuilding motor.
                        Tom

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                        • #27
                          Originally posted by tfburke3 View Post
                          If you have oil in the gas ,you have gas in the oil and you need tank repair or you will be rebuilding motor.
                          Tom
                          I am keeping an eye on it thanks

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                          • #28
                            ....so that post making intermittent contact with the distributor body may have been my problem. Back together now and had a 15 good mile road test. Gonna shoot for a 50 mile ride here shortly (I still don't trust it ).

                            Made a new insulator strip from a plastic milk jug for the points spring, put some heat shrink on the post where it passes through the distributor body, and used nylon washers inside and out.

                            BTW, when my reserve tank was leaking into my oil tank I stopped putting gas in the reserve until I could deal with it. Paying attention to the mileage and stopping every 75+/- miles for gas.
                            Pisten Bully is Harry Roberts in Vermont.

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                            • #29
                              ...sigh...23 miles is all I got this time. New coil is due in tomorrow.

                              If I put this coil in the oven, heat it up and test resistance between the two terminals, if the coil is good it should read the same, hot or cool...right? (...gotta find the actual problem before I trust it again.)

                              BTW, I did have a new condenser on it.
                              Last edited by pisten-bully; 07-19-2020, 01:49 PM.
                              Pisten Bully is Harry Roberts in Vermont.

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                              • #30
                                Have you thought about a jumper from the battery pos. to the coil to eliminate any switch or harness issues like Tom W mentioned?
                                At least it looks like you can cross dist. off the list.
                                Tom

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