Cummins ISX11.9 CM2250 – Service Manual 003-018   Crankcase Breather Tube

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

• Disconnect the batteries. Refer to the OEM service manaul.

Disconnect the crankcase breather vent tube (1), inlet tube (2), and drain line (3) from the crankcase breather.

Disconnect the crankcase breather inlet tube (2) from the rocker lever cover.

Remove the two p-clips securing the crankcase breather vent tube to the cylinder head and front gear housing.

Remove the crankcase breather vent tube.

Remove the p-clip securing the drain line to the intake manifold.

Disconnect the bottom of the drain line with the coupling from the block.

Remove the crankcase breather drain line.

WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

Check the tube and lines internally for obstructions or sludge buildup.

Clean the tube and lines with hot, soapy water and a soft brush.

Use compressed air to dry the tube and lines after rinsing in clean water.

Use air pressure to blow through the vent tube. Replace the vent tube if it remains clogged.

Inspect the breather drain line check valve for correct operation. A small amount of air can be blown through the line (less than 34 kPa [5 psi]) to check the check valve operation.

An obstructed drain tube or line will result in excessive crankcase pressure.

Install the crankcase breather drain line.

Connect the bottom of the drain line with the coupling to the block.

Install the p-clip securing the drain line to the intake manifold.

Connect the drain line to the crankcase breather.

Install the crankcase breather vent tube to the crankcase breather assembly.

One p-clip attaches the vent tube to the side of the front gear cover and one p-clip attaches the vent tube to the cylinder head. 

Install the p-clip that secures the crankcase breather vent tube to the cylinder head.

Install the p-clip that secures the crankcase breather vent tube to the front gear housing.

Connect the crankcase breather inlet tube (2) to the rocker lever cover.

Install the hose clamp.

Connect the crankcase breather vent tube (1), inlet tube (2), and drain line (3) to the crankcase breather.

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

• Connect the batteries. Refer to the OEM service manual.
• Operate the engine and check for leaks.