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Hot Start Pulse Relay Test

  1. If engine coolant is below 85°F (30°C), disconnect plug on cold start valve and connect test lamp across terminals. Remove coil high tension wire to prevent starting. Operate starter.
  2. On models without hot start pulse relay, test lamp will light for several seconds, then go out. On models with relay, lamp will continue to flash off and on.
  3. If lamp does not light, test thermo-time switch for continuity below opening temperature. If good, check wiring to starter terminal.
  4. Remove cold start valve from manifold but leave fuel line connected. Place valve in a container. See Fig 1 . Connect a jumper wire from one terminal to ground, and from other terminal of cold start valve to a switch. The other side of switch should be connected to a source of battery voltage.
    CAUTION: Do not connect wire directly to battery. Extreme fire danger is probable due to atomized fuel. Sparks may result if wire is touched to battery.
  5. Operate fuel pump. Turn switch to "ON" position. Cold start injector should spray. Turn switch "OFF", but leave fuel pump running. Injector should not spray. Wipe off nozzle and check for leakage. With pump running, no drops should form within one minute.
    Fig 1: Testing Cold Start Injector Valve After turning switch "OFF" (discontinuing electrical supply to valve), injector should cease spraying fuel.
    G34533
  6. Replace cold start valve if faulty. Install original valve if good, making sure that "O" ring is properly positioned.