Hino - TECH TIPS

The following lists all common Technical Tips for Hino Engines and DPF/SCR Systems.

For Pre-2010 engines, discard all maintenance items relating to the SCR System (I.E. SCR and DEF items).

For best diagnostic results use Hino DX2 software with NEXIQ2 adapter.

TIPS!

Engine Oil Level - Look not just for Low Level, but HIGH LEVEL. Fuel Dilution from failing Fuel Injectors, Cylinder Washout, Etc., can cause High Oil Levels (in addition to Coolant Entry).
Fuel and Oil Consumption - Check with Operator to determine if there has been recent increases in Fuel or Oil Consumption, or other changes in engine performance, such as low power, or frequent DPF REGENs required. With use of Hino DX2 or Scan Tool, the High Pressure Fuel Rail Pressure (Command) vs (Actual) can be tested under loaded engine conditions to determine if Fuel Injectors, Fuel Pump, or other HPCR Fueling Components are failing.

Diesel Fuel and DEF Fluid - Smell the Fluids to ensure an incorrect fluid, or deteriorated fluid exists in the tank. Contamination in fluids is a major problem in diesel applications (i.e. filling DEF tank w/diesel).
OIL in Engine Intake - Look closely for any Oil Leaks on the engine. Oil Entry into the CAC and Intake is a very common problem due to lack of Crankcase Breather Element replacements. This causes Soot/Oil to mix in the EGR System and cause major engine problems.

SOOT in Intake - The DPF System (Burner Style) have a Combustion Air Valve (CAV VALVE) that commonly sticks open, allowing soot to enter the intake and CAC. CAV replacements are common.

DPF CORE & DOC CORE Inspection - Loss of DPF Core Retention can happen on Hino DPF Systems. When removing the DPF/DOC Cores for cleaning, carefully inspect to ensure there is no loss in Core Retention.

DOC CORE Matt Material - Inspect the face of the DPF CORE and SCR CORE for signs of Face Plugging. In addition to general Soot Face Plugging, often the Matt Material that separates the DOC Core from the Steel Body begins to loosen, and ends up face plugging the DPF/SCR Cores downstream. Additional damage to the DPF, DOC, and SCR Cores may ensure.

DPF REGEN Full Test - Running a DPF Parked REGEN can provide significant info on the DPF (and engine) Performance. Look at Exhaust Temps over duration of REGEN and compare to proper running REGEN. As with most DPF Systems, the exhaust temperature downstream of the DPF should exceed 1,000F within ~15min of starting the REGEN.

DPF BURNER SYSTEM - Hino model years 2007-2014 generally utilize a "Burner Style DPF System". There are (2) Spark Plugs, and (1) Fuel Nozzle. These Spark Plugs need to be replaced frequently, and the Fuel Nozzle requires cleaning.

DPF CATALYZED SYSTEM - Hino model years 2015-Present utilize a Catalyzed DPF (non-Burner). There is a DPF Fuel Injector in the exhaust, just downstream of the Turbocharger. The solenoid valve in this Fuel Injector can fail. If the DPF PARKED REGEN fails to run, often the Fuel Injector requires replacement.