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Subject: Fuel Shut off valve leak -53 Jubilee

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Roadrunner    Posted 11-28-2017 at 15:41:49 [URL] [DELETE]        [Reply] [Email]  
  • Fuel Shut off valve leak -53 Jubilee
  • Hey Guys, I always appreciate reading through this forum... great stuff!

    My Jubilee fuel shut off valve has been leaking pretty steady as of late, its really starting to make my garage stink, and Im running out of card board and ply to absorb the run off. Im a mechanical novice, but willing to attempt pretty much anything. Is there a fix for the leaky valve, does it need to be replaced, what exactly needs to be replaced and what skill level is required to make the repair?
    Thanks again,

    Tim Daley(MI)    Posted 11-29-2017 at 06:50:41 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Fuel Shut off valve leak -53 Jubilee
  • Meep, Meep!
    Leaking Sediment Bulb Assemblies usually are due to the internal seal on the valve stem being worn. The seal is the major ‘wear’ part on the assembly, all others being strictly mechanical. The only other possible leaking issue would be if the fuel line threads are boogered up/cross threaded. They are a special thread size, 7/16-24”, and once the fuel line outlet port or the valve stem inlet port on the bulb assembly gets cross-threaded, it will never seal right and thus leak. Causes of cross-threading can be from overtightening, forcing the line fitting in when starting it and causing the action, or attempting to ‘re-thread’ the port with the wrong size tap or the line fitting with the wrong size thread die. Always start the line fitting and valve stem by hand to ensure they are correctly aligned. Thread them in as far as possible by hand before tightening with a wrench. There is no need to replace the entire sediment bulb unless either of these threads is cross-threaded. Once cross-threaded there is no way to correct them even if you have the right size tap or die. The Valve Stem Assembly, p/n APN9191, can be purchased new for about $6 at the right place. It comes with a new knurled ON/OFF knob as well. This knob is fastened onto the valve stem with an 8-32 screw. Most all new ones will often fail in the field from vibration causing the knob to work itself off the stem and is lost forever. To correct this from occurring, I always apply a dab of thread sealant on it when replacing the valve stem on a sediment bulb. There is never going to be a need to ever remove it until the next time you need a new valve stem and the new stem kit contains a new knob and screw. Some folks think using Teflon Tape is the solution, but I avoid using Teflon Tape on these old N fuel systems. I’ve worked on many carburetors with pieces of Teflon Tape obstructing the sediment bulb and/or the carb fuel filter brass inlet elbow screen. Besides, the tape is only a temporary band-aid fix anyway. It would be OK in a pinch when you absolutely need to get the field plowed or hay mowed, but don’t rely on it for a permanent fix. Leaking fuel systems are a safety hazard. Do It Right The First Time, Dr. Demmings’ 1st law, has been my mantra since studying his manufacturing practices.


    2N-9155-B SEDIMENT BULB ASSEMBLY; 39-54:



    Tim Daley(MI)

    Greg W    Posted 11-28-2017 at 18:20:07 [URL] [DELETE]        [Reply] [Email]  
  • Re: Fuel Shut off valve leak -53 Jubilee
  • I do not have the link available, you may have to Google.
    I just rebuilt my valve, removed the stop pin, used 9/64" drill and 10-32 tap
    to allow a 10-32 screw to replace the stop pin.
    New Orings (needed about every 18 months I read)and put it back together.
    The 10-32 screw allows you to take the brass stop knob off to replace Orings without
    removing the tank a second time.

    Dave H    Posted 11-28-2017 at 18:11:56 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Fuel Shut off valve leak -53 Jubilee
  • When that happens to me, I try to find out what is leaking/where.

    Maybe just as gasket, who knows until you identify the source.

    grizz    Posted 11-28-2017 at 16:36:38 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Fuel Shut off valve leak -53 Jubilee
  • have you tried to tighten the nut where the valve shaft goes through also if it has a sediment bowl could have a bad gasket if it is leaking that much dry it off and wait and feel around till you find it

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