Cummins ISX11.9 CM2250 – Service Manual 006-012   Fuel Drain Line Restriction

The fuel drain line restriction is measured at the fuel drain manifold.

Remove the banjo bolt from the fuel injector drain connection at the fuel drain manifold.

Install the banjo test fitting, Part Number 4918413, in place of the banjo bolt. Install Compuchek™ fitting, Part Number 3042618 or equivalent, into the banjo test fitting.

Attach a 0 to 762 mm-Hg [0 to 30 in-Hg] pressure/vacuum gauge to the banjo test fitting at the fuel injector drain connection at the fuel drain manifold.

Operate the engine at cranking speed, low idle, or high idle and measure the fuel pressure.

Observe the reading on the gauge.

Drain Line Restriction

If the fuel drain line restriction is too high:

• Check the OEM fuel lines to the tank for proper size, leaks, bends, or clogs.
• Check the fuel tank vents for plugging.