301-66136-0 Nissan O-RING, 1.9 - 8.8

Measurement Of Pressure In Inlet Manifold
Table 1
Tools Needed    
Part Number    Part Description    Qty    
1U-5470     Engine Pressure Group     1    
8J-7844     Adapter Fitting     1    
3K-0360     O-Ring Seal     1    
4M-5317     Terminal Bushing     1    Measure the pressure in the inlet cover. Compare the pressure in the inlet cover to the information in the Technical Marketing Information (TMI). This will indicate the efficiency of the engine.This test is used when there is a decrease of horsepower from the engine, yet there is no actual sign of a problem with the engine.The correct pressure for the inlet manifold is also given in the Technical Marketing Information (TMI), "Fuel Setting and Related Information". These standards are established under the following conditions:
96 kPa (28.8 inches of Hg) dry barometric pressure
25°C (77°F) outside air temperature
35 API rated fuelAny change from these conditions can change the pressure in the inlet manifold. The outside air may have a higher temperature and a lower barometric pressure than the values that are given above. This will cause a lower inlet manifold pressure measurement than the pressure in the TMI. Outside air that has both a lower temperature and a higher barometric pressure will cause a higher inlet manifold pressure measurement.A difference in fuel density will change horsepower (stall speed) and boost. If the fuel is rated above 35 API, the pressure in the inlet manifold can be less than the pressure that appears in the TMI. If the fuel is rated below 35 API, the pressure in the inlet manifold can be more than the pressure that appears in the TMI. BE SURE THAT THE AIR INLET OR THE EXHAUST DOES NOT HAVE A RESTRICTION WHEN YOU ARE MAKING A CHECK OF THE PRESSURE.Note: The electronic service tool may be used to check the pressure in the inlet manifold.
Illustration 1 g00295554
1U-5470 Engine Pressure Group
Illustration 2 g00295555
Pressure Test Location (1) Plug.To check the inlet cover's pressure, remove one of the plugs (1) on the top of the inlet cover. Connect the following items to this opening:
adapter
seal
reducing bushing
1U-5470 Engine Pressure Group The 1U-5470 Engine Pressure Group has a gauge that indicates pressure inside the inlet cover. Instructions for using this tool group appear in the Special Instructions, SEHS8524.Measurement Of Exhaust Temperature
Table 2
Tools Needed    
Part Number    Part Description    Qty    
123-6700     Infrared Thermometer     1    When the engine runs at low idle, the temperature of an exhaust manifold port can indicate the condition of a unit injector:A low temperature indicates that no fuel is flowing to the cylinder. An inoperative unit injector pump could cause this low temperature.A very high temperature can indicate that too much fuel is flowing to the cylinder. A malfunctioning unit injector could cause this very high temperature. Use the 123-6700 Infrared Thermometer to check this exhaust temperature. You can find operating instructions and maintenance instructions inside the Operator's Manual, NEHS0630, "123-6700 Infrared Thermometer II with Laser Sighting".Air-to-Air Aftercooled Systems
Table 3
Tools Needed    
Part Number    Part Description    Qty    
FT-1984     Aftercooler Testing Group     1    
FT-1438     Dynamometer Testing Aftercooler     1    Visual Inspection
Inspect the following components of the air-to-air aftercooler system:
all lines
all hoses
all gasket jointsMake sure that the constant torque hose clamps are tightened to the correct torque. Check the truck manufacturer's specifications for the correct torque. Check the welded joints for any cracks. Check the brackets for correct positioning. Also, make sure that these brackets are in good condition. Use compressed air to clean any debris or any dust from the aftercooler core assembly. Inspect the aftercooler core assembly's fins for the following conditions:
damage
debris
salt corrosionUse a stainless steel brush to remove any corrosion. Make sure that you use soap and water.
Pressurized air can cause personal injury. When pressurized air is used for cleaning, wear a protective face shield, protective clothing, and protective shoes.
Note: When air-to-air aftercooler parts are repaired and air-to-air aftercooler parts are replaced, a leak test should be completed. Do not