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Diesel Ad Rollngo Caddy
Engine difficult to start with smoke




Starting procedure is incorrect

Verify proper starting procedures. Refer to the starting procedure in the owners Operation and Maintenance Manual

Cranking speed too slow (minimum cranking speed 150 rpms

Verify the driven units are not engaged. Check the battery starting motor and look for loose or corroded wiring connections. Bar the engine to check for internal rotational resistance.

Starting aid needed for cold weather or not working properly.

Check and repair or replace the cold starting aid, if necessary. Refer to the OEM trouble-shooting and repair manual for recommendations

Intake air inadequate or overheated

Inspect/replace the air cleaner element and look for restrictions. * If the vehicle is equipped with a valve to switch the intake source from under the hood to outside, position the valve for the season. * Check the charge air cooler for internal restriction. Replace the restricted cooler. * Check and clean the debris from the front of the change air cooler.

Air in the fuel system

Bleed the fuel system and check for suction leaks

Fuel Supply Inadequate

Check the flow through the filter to locate the source of restriction

Fuel quality poor or diesel fuel grade No. 1 used above 32 deg F

Verify by operating the engine form a temporary tank of No. 2 diesel fuel.

Fuel drain back

Verify the fuel return line is plumbed to the bottom of the fuel tank if applicable

Malfunctioning fuel return overflow valve

Check/replace the return overflow valve

Fuel inlet restriction

Maximum inlet restriction to the fuel transfer pump must not exceed 100 mm Hg (4 in. Hg)

Fuel injection pump timing is incorrect

Check and adjust the injection pump timing to engine manufacturer specs

Valves incorrectly adjusted (valves are not sealing)

Check and adjust the valves

Injectors worn or malfunctioning

Check the injectors and replace any malfunctioning injectors


Perform the compression check to identify the malfunction.

Fuel injection pump malfunctioning/delivery valves malfunctioning

Remove the fuel injection pump and repair as necessary