03 night train, won't idle, coughs and backfires.

Discussion in 'Engine, Fuel and Exhaust' started by jigglestick, Aug 2, 2014.

  1. jigglestick

    jigglestick Member

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    Wondering if I could get some advice on my wife's 03 Night Train (carb) before I dig too deep.

    The bike is pretty much stock. Bought it used and, as far as I can tell, it has no tuners, etc added. The bike ran fan all last year. We put it away in the fall and it has been in heated storage ever since. This is actually the first time it has been started since late fall. When we put the bike away, we treated the gas and removed the battery.

    Yesterday, I installed a new battery and fired it up. Ran sorta rough and it required, at least, half choke to stay running. I took it down the road and it accelerated fine, but at cruising speed, it would cough behind the air cleaner and occasionally backfire. Every time I slowed for a stop sign, and pulled in the clutch, it would die. Letting out the clutch while in the next lower gear, it would fire right back up. Had to work the throttle to keep it running. Again, half choke would keep it running.

    I brought it home, filled the tank with fresh gas. Dumped some Seafoam in the tank. Ran it at high RPM for a bit. Still no change. I have heard that by running high RPM and slapping your hand against the carb intake, that it might dislodge any plugging. I removed the air cleaner and tried that a few times. I sprayed carb cleaner looking for a change in RPM, indicating an intake leak. Seemed ok.

    We leave for Sturgis in two days. Any suggestions would be greatly appreciated.
    [​IMG]
     
  2. Jack Klarich

    Jack Klarich Expert Member

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    Last edited by a moderator: Aug 2, 2014
  3. jigglestick

    jigglestick Member

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    Thanks Jack. Gonna give that a shot. It's just that you hear so much about sensors and modules going bad, you know?
     
  4. Jack Klarich

    Jack Klarich Expert Member

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    Half choke tells me you are lean running out of fuel:s
     
  5. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    I am guessing that even though you treated the gas when you put it up last fall, you still had some gumming in the fuel system. I would disassemble the carb, clean everything carefully, spray through the jets with carb cleaner, inspect the main diaphragm for holes or cracks, and the condition of the accelerator pump diaphragm (should be OK since you say you have good acceleration), then reassemble. Check the function of the VOES if your carb has one. Replace all the vacuum lines especially the one to the vacuum actuated tank valve if so equipped.

    Hope this solves it.

    Cheers,

    TQ
     
  6. Jack Klarich

    Jack Klarich Expert Member

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    [​IMG]
    Here is your carb

    [​IMG]
    Check # 17
     
    Last edited by a moderator: Aug 3, 2014
  7. jigglestick

    jigglestick Member

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    Yup. Kinda suspected some sort of clog or gumming myself. Thought that would be my only option here. To remove carb and disassemble. Thanks guys. Just wish that wasn't just a tad over my experience. Fingers crossed.

    Jack. The exploded view of the carb is great, but identifying each numbered part would be really nice. Anyway that you can post the key for that drawing? Specifically, I'm looking for the idle air mixture screw. I would like to take it out and clean out the ports, etc. It seems logical since I have to give it half choke to keep it running, that it isn't getting fuel on the idle circuit.
    [​IMG]
     
    Last edited by a moderator: Aug 3, 2014
  8. dolt

    dolt Senior Member Contributor

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    The VOES was replaced with a MAP sensor on the twin cams. I would certainly pull the carb, disassemble, clean, set float level. If the A/F adjustment screw is still behind the plug, remove the plug so you can play with the A/F adjustment. If that doesn't correct things, pull the CPS and check for gunk.
     
  9. jigglestick

    jigglestick Member

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    Thanks guys. I know it seems easy to you guys. But at my level? Forget it. Looks like we either take the car to Sturgis or call the trip off. I will take it in some other day.
     
  10. Jack Klarich

    Jack Klarich Expert Member

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    F.
    NO. PART NO. CARBURETOR ASSEMBLY
    DESCRIPTION NIGHT
    TRAIN RETAIL
    PRICE EACH Ronnies'
    PRICE EACH
    1 3275 SCREW 4 2.09 1.88
    2 10014 CLAMP 2 1.05 0.95
    3 26995-86B SEAL, INTAKE MANIFOLD 2 2.48 2.23
    4 27002-89 SEAL RING 1 8.62 7.76
    5 27009-86A FLANGE, MOUNTING -FRONT 1 6.00 5.40
    6 27010-86A FLANGE, MOUNTING - REAR 1 6.00 5.40
    7 27613-99 MANIFOLD 1 89.95 80.96
    8 27100-88 NEEDLE JET 1 8.36 7.52
    9 27101-88 NEEDLE JET HOLDER 1 8.36 7.52
    10 27243-95 MAIN JET 1 7.06 6.35
    11 27122-89 ROD 1
    12 27124-89 E-CLIP 1 0.78 0.70
    13 27125-89 WASHER 1 1.05 0.95
    14 27126-89 LEVER 1 8.62 7.76
    15 27127-89 WASHER 1 1.05 0.95
    16 27128-89 PIN 2 0.52 0.47
    17 27130-90 IDLE SCREW 1 1.05 0.95
    18 27136-90A SPRING 1 2.09 1.88
    19 27137-81 WASHER 1 1.05 0.95
    20 27146-89 SCREW W/ WASHER 3 1.57 1.41
    21 27147-89 COLLAR 1 0.60 0.54
    22 27148-89 WASHER 1 1.05 0.95
    23 27156-89 ROD 1 2.87 2.58
    24 27260-00 PUMP HOUSING 1 34.50 31.05
    25 27162-89 SPRING 1 3.55 3.20
    26 27170-89 SLOW JET 1 8.36 7.52
    27 27231-98 COLLAR 1
    28 27261-96 TOP, CARBURETOR 1 10.98 9.88
    29 27262-96 SCREW, TOP 3 1.05 0.95
    30 27263-96 COLLAR, CARB TOP 1 1.57 1.41
    31 27421-99C CARBURETOR 1 444.32 399.89
    31 27414-99C CARBURETOR (CAL. ONLY) 1 444.32 399.89
    32 27311-76 BOOT, ACCELERATOR PUMP 1 3.66 3.29
    33 27315-88A SPRING 1 1.57 1.41
    34 27317-88 SCREW 1 1.05 0.95
    35 27339-90 BRACKET, THROTTLE CABLES 1
    36 27360-76 O-RING 1 1.30 1.17
    37 27361-76A DIAPHRAM, ACCELERATOR PUMP 1 15.68 14.11
    38 27362-76 SPRING, DIAPHRAGM 1 1.30 1.17
    39 27371-76A FITTING 1 11.76 10.58
    40 27405-00 CHAMBER ASSEMBLY, CARBURETOR FLOAT 1 112.91 101.62
    41 27575-88A PIN 1 2.09 1.88
    42 27576-92 FLOAT 1 13.07 11.76
    43 27577-92 O-RING, FLOAT CHAMBER 1 4.31 3.88
    44 27579-88A SCREW 4 2.09 1.88
    45 27580-88 CABLE GUIDE 1 3.92 3.53
    46 27581-88 STARTER CAP 1 4.70 4.23
    47 27582-88 CABLE SEALING CAP 1 3.40 3.06
    48 27583-88 STARTER VALVE 1 6.90 6.21
    49 27585-88 VACUUM PISTON 1 48.09 43.28
    50 27586-88 SPRING SEAT 1 5.75 5.18
    51 27587-88 SCREW 1 1.05 0.95
    52 27886-78A VALVE, WITH CLIP 1 20.54 18.49
    53 28025-03 JET NEEDLE - N9E 1 8.36 7.52
    54 62555-95 INSULATOR, 5/8" I.D. (NYLON) (8 FT. LG.) (SEE NOTE) 1 10.04 9.04
    55 63501-68A HOSE, 1/4" I.D. X 5/8" O.D. (RUBBER) (25' LENGTH) (SEE NOTE) 1 99.98 89.98
    Here is the legend for the carb parts