High Fuel Pressure
To determine if high fuel pressure is causing lack of power, perform the following steps:
- Remove either the fuel pressure sensor (FPS) or fuel temperature sensor (FTS) fitting from the secondary filter, if equipped; see Figure
"Engine Fuel Pressure Sensor "
for FPS, and see Figure
"Engine Fuel Temperature Sensor"
Figure 1. Engine Fuel Pressure Sensor
Figure 2. Engine Fuel Temperature Sensor
- Install a tee fitting between the secondary filter and fuel outlet line.
- Attach a calibrated gauge capable of reading 0-100 lb·in.2 to the tee fitting.
- Start and run the engine to the speeds, listed in Table
"Fuel Pressure at Various Speeds"
, and record the fuel pressure:
103-151 kPa (15-22 lb/in.2 )
207-310 kPa (30-45 lb/in.2 )
448-483 kPa (65-70 lb/in.2 )
- Shut down the engine.
- Remove the tee fitting and calibrated gauge from the secondary filter.
- Reinstall the FTS, refer to "2.24.3 Installation of Fuel Temperature Sensor" or FPS sensors, refer to "2.23.3 Installation of Fuel Pressure Sensor" ; whichever was removed.
- Analyze the measured fuel pressure readings.
- If the fuel oil pressure is within specification, listed in Table "Fuel Pressure at Various Speeds" , check for high fuel oil temperature return; refer to "25.3 High Fuel Oil Temperature Return" .
- If the fuel oil pressure is greater than specifications, listed in Table "Fuel Pressure at Various Speeds" , refer to "25.2.1 Restricted Fitting and Check Valve Replacement" .
Restricted Fitting and Check Valve Replacement
Perform the following steps to replace the restricted fitting and check valve.
- Remove the restricted fitting; refer to "2.8.2 Fuel Return System Check Valve" .
- Install a new restricted fitting; refer to "2.8.4 Installation of PRO-CHEK ® Fuel System Check Valve" .
- Remove the check valve; refer to OEM guidelines.
- Install a new check valve; refer to OEM guidelines.
- Verify check valve and restricted fitting replacement; refer to "18.104.22.168 Test the Engine with Replaced Check Valve and Restricted Fitting" .
Test the Engine with Replaced Check Valve and Restricted Fitting
Perform the following to determine if the replaced check valve and restricted fitting resolved lack of power condition:
- Start and run the engine.
- Run the engine at idle with a no-load for approximately 5 minutes, allowing the engine coolant to reach normal operating range.
- Test drive the vehicle to ensure lack of power has been resolved.
- If no lack of power occurred during the test drive, no further troubleshooting is required. Shut the engine down.
- If lack of power occurred during the test drive, shut the engine down. Check for high fuel oil temperature return; refer to "25.3 High Fuel Oil Temperature Return" .
|Series 50 Service Manual - 6SE50|
|Generated on 10-13-2008|