Test Sequence for Pencil Type Fuel Nozzles{1254} Caterpillar

Machine Engines: 3204 3208 3304 3306

Engine:

1140 (S/N: 36B1-UP)

1145 (S/N: 97B1-UP)

1150 (S/N: 96B1-UP)

1160 (S/N: 95B1-UP)

3145 (S/N: 65P1-UP)

3150 (S/N: 66P1-UP)

3160 (S/N: 98M1-UP; 67P1-UP)

3208 (S/N: 29A1-UP; 30A1-UP; 5YF1-UP; 40S1-UP; 75V1-UP; 32Y1-UP; 02Z1-UP; 51Z1-UP)

Introduction

This Special Instruction has been written in order to provide procedural information for testing pencil type fuel nozzles.

There is an extensive amount of information that relates to the setup and the calibration of the tools that will be used to test the fuel nozzles.

Additionally, there is information on the setup and operation of the cleaning equipment that is necessary in order to properly clean the fuel nozzles.

There is also a publication that provides record sheets. These record sheets can be used for recording and correlating the test data that is accumulated. The following information will summarize the related documentation.

• For information on the setup, operation, and the calibration of the test equipment, refer to Tool Operating Manual, SEHS7292, "Using the 5P-4150 Nozzle Testing Group".

• For information that relates to the setup and operation of the tools that are used to clean fuel nozzles, refer to Special Instruction, SEHS8627, "Using the 8S-2245 Nozzle Cleaning Tool Group".

• Use the Special Instruction, SEHS8144, "Engine Nozzle Test Record" in order to record the results while you are testing each fuel nozzle. These record sheets are available through normal channels for literature distribution. The record sheets are available in pads that contain 50 sheets.

Note: The publications that are mentioned above may contain information that must be referenced in order to test the fuel injection nozzles.

Testing Pencil Type Fuel Nozzles

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Ensure that you wear eye protection at all times during testing. When fuel injection nozzles are tested, test fluids travel through the orifices of the nozzle tip with high pressure. Under this amount of pressure, the test fluid can pierce the skin and cause serious injury to the operator. Always keep the tip of the fuel injection nozzle pointed away from the operator and into the fuel collector and extension.

Note: Prior to starting this test procedure, the 5P-4150 Nozzle Testing Group must be equipped with a 8T-0860 Pressure Gauge . Replace the original 8T-0859 Pressure Gauge with the 8T-0860 Pressure Gauge . Refer to Tool Operating Manual, SEHS7292, "Using the 5P-4150 Nozzle Testing Group" for information that relates to the replacement of the pressure gauge.

Visual Inspection of the Fuel Nozzle

Perform a visual inspection of the fuel nozzle. Inspect each fuel nozzle for any sign of damage that may contribute to the improper operation of the fuel nozzle. Check for signs of damage that may have been caused by any of the following conditions:

• Engine overheating (discolored fuel nozzles)

• Improper cleaning (use of a wire brush for cleaning)

• Partially melted carbon dam seal

• Fuel nozzles that are deformed or bent

• Cracking or splitting of the nozzle tip

• Other obvious damage

Note: If there are signs of engine overheating, all of the fuel nozzles must be replaced.

If any of these forms of damage has been found, do not use the damaged fuel nozzle.

Install the Fuel Nozzle onto the Test Fixture

Remove the Cap from the Fuel Nozzle

The cap must be removed from the fuel nozzle in order to prevent hydraulic lock during the testing procedure. Use the following steps in order to remove the fuel nozzle's cap.

1. Secure the 8S-2250 Nozzle Holding Tool into a vise.

2. Install the fuel nozzle into the holding tool.

3. Use a wrench to remove the cap from the fuel nozzle.

4. Remove the fuel nozzle from the holding tool.

Install the Fuel Nozzle onto the Tester

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Illustration 1	g00935081

1. Install the tube assembly (1) onto the test fixture. For pencil type fuel nozzles, use the 6V-2171 Tube As (1) .

2. Install the nozzle adapter (2) onto the tube assembly.
   • For the 7N-0449 Fuel Nozzle , install a 5P-4244 Adapter onto the tube assembly.

   • For pencil type fuel nozzles except the 7N-0449 Fuel Nozzle , install a 5P-7448 Adapter onto the tube assembly.

   Note: Be sure to check the test fixture for leaks prior to performing this test procedure. Refer to Tool Operating Manual, SEHS7292, "Using the 5P-4150 Nozzle Testing Group" for information that is related to the operation of the nozzle testing group.

3. Position the fuel nozzle onto the tube assembly and hand tighten the nozzle to the adapter fitting.

4. Open the pump isolator valve for one-half turn.

5. Open the gauge protector valve (0 to 40,000 kPa (0 to 5,800 psi) gauge) for one-half of a turn.

6. Place the 8S-2270 Fuel Collector and the 1U-8857 Extension Tube under the fuel nozzle.

Bleed the Air from the Nozzle Assembly

1. Loosen the adapter fitting at the fuel nozzle.

2. Operate the pump handle until test fluid that is free of air bubbles flows from the threads of the adapter.

3. Hand tighten the adapter fitting.

Test for Internal Return Leakage

1. Loosen the adapter fitting and rotate the fuel nozzle on the tube assembly. Rotate the fuel nozzle until the tip of the nozzle is raised slightly above the horizontal position. The nozzle should be positioned in a manner that will allow the test fluid to drip from the top portion of the fuel nozzle.

2. Tighten the adapter fitting to the fuel nozzle.

3. Wrap a clean cloth around the fuel nozzle's tip in order to absorb any test fluid that may escape from the tip.

4. Pump the tester until a pressure of 10,500 kPa (1525 psi) is attained on the pressure gauge. Close the pump isolator valve.

   Note: The pump isolator valve should be used to adjust the tester to the correct test pressure. Do not place excessive pressure on the nozzle assembly during this test.

5. Allow two drops of test fluid to fall from the fuel nozzle. The test begins as the second drop of test fluid is observed to fall. Hold the test pressure for an additional 30 seconds after the second drop.

6. Count the number of drops of test fluid that drips from the nozzle during the 30 second duration of the test. Open the pump isolator valve in order to release the pressure on the fuel nozzle when the test is completed.

   Refer to the information that is provided in Table 1 in order to evaluate the results of the test.

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   Table 1

   Specifications for Internal Return Leakage (Leakage within 30 seconds after two drops of test fluid are allowed to drip from the tip of the nozzle.)
   Nozzle Assembly	Minimum	Maximum
   1W-5829	(1)	(1)
   4W-1819
   4W-8483
   7E-3969
   7N-0449
   7W-3710
   7W-8043
   9N-3979
   101-0060
   115-3354
   122-9007
   9L-7883	1 drop	10 drops
   9L-9263
   9N-2366
   9L-6969	2 drops	30 drops
   9N-3299
   9N-3700

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   ( 1 )

   No minimum or maximum specification

   If the fuel nozzle is not within specifications, stop the test and do not use the nozzle.

Valve Opening Pressure Test

1. Loosen the adapter fitting and rotate the fuel nozzle on the tube assembly. Place the tip of the fuel nozzle inside the fuel collector extension. Adjust the fuel nozzle to the vertical position and tighten the adapter fitting.

2. Wrap a clean cloth around the top of the fuel nozzle in order to absorb any internal return leakage.

3. Slowly increase the pressure on the fuel nozzle until fluid begins to flow from the tip of the fuel nozzle. Record this pressure as the valve opening pressure of the fuel nozzle. Refer to the information that is provided in Table 2 in order to evaluate the results of the test.

If the fuel nozzle is not within specifications, stop the test and do not use the nozzle.

Check for Tip Leakage

1. Close the gauge protector valve (0 to 40,000 kPa (0 to 5,800 psi) gauge).

2. Flush the fuel nozzle that is being tested by pumping the tester for 3 full strokes.

3. Open the gauge protector valve (0 to 40,000 kPa (0 to 5,800 psi) gauge).

4. Use a clean cloth to dry the tip and the body of the fuel injector. All test fluid should be wiped from the nozzle assembly.

5. A clean cloth should be wrapped around the top of the fuel nozzle in order to absorb any internal return leakage.

6. Calculate the test pressure that will be used for the tip leakage test.

   Use the fuel nozzle's valve opening pressure, that has been previously recorded, in order to calculate the test pressure for the nozzle that is being tested.

   1. Subtract a value of 1875 kPa (275 psi) from the valve opening pressure that was previously obtained.

   2. Record the result of the calculation as the test pressure that will be used for the tip leakage test.

7. Slowly apply the test pressure, that has been calculated in Step 6, to the fuel nozzle.

8. Close the pump isolator valve.

9. Hold this test pressure for 10 seconds.

10. Count the number of drops of test fluid that drips from the nozzle during the duration of the test. Open the pump isolator valve in order to release the pressure on the fuel nozzle when the test is completed.

    Refer to the information that is provided in Table 3 in order to evaluate the results of the test.

    Note: Ensure that any test fluid that collects on the tip of the fuel nozzle is not fluid leakage from the test fixture.

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    Table 3

    Specifications for Tip Leakage (Leakage within 15 seconds after the test pressure is applied to the nozzle.)
    Nozzle Assembly	Maximum Leakage
    1W-5829	20 drops (1)
    4W-1819
    4W-8483
    7E-3969
    7N-0449
    7W-3710
    7W-8043
    9N-3979
    101-0060
    115-3354
    122-9007
    9L-7883	3 drops (1)
    9L-9263
    9N-2366
    9L-6969	30 drops (1)
    9N-3299
    9N-3700

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    ( 1 )

    No minimum specification

    If the tip leakage for the fuel nozzle is not within specifications, stop the test and do not use the fuel nozzle.

Test the Fuel Nozzle for Plugged Orifices

Illustration 2	g00923165
Spray patterns for pencil type fuel nozzles.

1. Close the gauge protector valve (0 to 40,000 kPa (0 to 5,800 psi) gauge).

2. Rapidly increase the pressure on the fuel nozzle until fluid sprays from the tip of the fuel nozzle.

   Note: For this test, each full stroke of the pump should be performed in less than one second.

3. Test fluid should spray from the tip of the nozzle in a pattern that is uniform. Refer to Illustration 2 for representations of the spray patterns that can be produced by pencil type fuel nozzles. The 7N-0449 Fuel Nozzle is the only pencil type fuel nozzle that produces a spray pattern from eight orifices. All of the other pencil type fuel nozzles produce a spray pattern from four orifices.

If an orifice is plugged or the pattern is distorted, clean the fuel nozzle's orifice(s) and repeat this test. Refer to Special Instruction, SEHS8627, "Use of 8S-2245 Nozzle Cleaning Tool Group" for instructions on tool usage and cleaning procedures.

Damage to the fuel nozzle's orifice(s) can cause the engine to have a large change in horsepower. A spray pattern that is distorted can cause the engine to run rough. If an acceptable spray pattern can not be obtained, the fuel nozzle that is damaged must be replaced.

Check the Cap for Leakage

Reinstall the Cap onto the Fuel Nozzle

1. Loosen the adapter fitting from the fuel nozzle.

2. Remove the fuel nozzle from the test fixture.

3. Install the nozzle into the 8S-2250 Nozzle Holding Tool . Secure the holding tool into a bench vise.

4. Install a new O-ring seal for the cap onto the fuel nozzle and install the cap. Use your fingers to hand tighten the cap onto the fuel nozzle.

5. Tighten the cap to a torque of 12 to 14 N·m (8.9 to 10.3 lb ft).

   Note: Do not apply excessive torque when the cap is being installed. This could cause damage to the cap and to the fuel nozzle.

6. Remove the nozzle assembly from the holding tool and reinstall the nozzle into the test fixture.

7. Position the nozzle so that the spray pattern is directed into the fuel collector. Tighten the adapter assembly to the fuel nozzle.

Cap Leakage Test

1. Remove the air from the fuel nozzle by pumping the tester several times. Pump the tester until the cap of the fuel nozzle is full of test fluid.

2. Pressurize the nozzle assembly to 20,700 kPa (3,000 psi).

   Note: 15 to 20 strokes may be required to reach the test pressure. A hydraulic lock can prevent the nozzle from opening when the cap is completely full of test fluid.

3. Inspect the nozzle assembly for leakage around the cap.

   Test fluid should not leak from the cap of the nozzle. If leakage is present and the fuel nozzle cannot be repaired, do not use the nozzle.

4. Remove the fuel nozzle from the tester.

For fuel nozzles that have completed the testing successfully, install a new compression seal and a new carbon dam seal prior to returning the fuel nozzle to service.