Usage:
Introduction
The 1U5470 Engine Pressure Group is the replacement for the 6V3150 and 6V9450 Engine Pressure Groups. It is also a replacement for the 4S6553 Engine Evaluation Test Group.
The piece parts in the 6V3150 and 6V9450 Engine Pressure Groups are still serviced. But the parts in the 4S6553 Engine Evaluation Test Group are no longer serviced.
Either the 6V3150 or the 6V9450 Engine Pressure Group can be updated to the status of the 1U5470 Engine Pressure Group. Refer to the topic entitled Procedure for the Update of a 6V3150 or a 6V9450 Engine Pressure Group in this publication.
The 1U5470 Engine Pressure Group can be used to check the performance of both diesel and natural gas engines, and to make operating adjustments to natural gas engines. Refer to the Service Manual of the engine being serviced, or, the Fuel Setting and Related Information Microfiche Library, Form SBFY1108, for the operating specifications that are needed.
The gauges in the 1U5470 Engine Pressure Group are gauge pressure instruments that indicate pressure relative to ambient atmospheric pressure. This type of instrument will read ZERO when the pressure port is open to the atmosphere.
Engine boost or manifold pressure is the difference between atmospheric pressure and the pressure in the engine intake manifold. The 1U5469 Pressure Gauge can read boost directly in kPa and inches of Hg.
The 8T0839 Differential Pressure Gauge reads directly in kPa and inches of H2O. All other gauges in the group read directly in kPa and psi.
The chart in the lid of the case can be used to convert kPa or psi to inHg (inches of mercury) as shown in the Fuel Setting and Related Information Microfiche. No allowance for atmospheric pressure is needed in the conversion.
NOTE: The metric portion of the new pressure gauges is shaded in yellow.
Components of the 1U5470 Engine Pressure Group
1. 8T0841 Case. 2. SEES5677 Conversion Chart. 3. 8T0846 Pressure Gauge. 4. 8T0838 Bulkhead Fitting (eight)1. 5. 1U5469 Pressure Gauge (or optional 8T0840 Pressure Gauge). 6. 8T0839 Differential Pressure Gauge. 7. 8T0848 Pressure Gauge (three). 8. 8T3153 Foam Block2. 9. 6V6115 Packing Set Base. 10. 8T0835 Union1 (two). 11. 8T0452 Water Manometer (optional) and 1U5554 Panel Assembly (optional). 12. 8T0837 Straight Connector (six)1. 13. 8T0836 Elbow Fitting (six)1. 14. 8T0821 Tubing3, 16 m (52.5 ft). 15. 6V6045 Accessories Case and NEEG2061 Accessories Label.1/8
1The 8T0835 Union, 8T0836 Elbow Fitting, 8T0837 Straight Connector and 8T0838 Bulkhead Fitting are reusable " tube fittings for applications in the pressure range of vacuum to 1720 kPa (250 psi) and in temperatures from -12°C to 200°C (10°F to 400°F).
2The optional 8T3117 Foam Block can be positioned in the lid of the 8T0841 Case to hold the optional 8T0452 Water Manometer in the case with the 1U5470 Engine Pressure Group.
3The 8T0821 Tubing is a coil of 16 m (52.5 ft) of clear nylon tubing that permits the user to see fluid in it before and during use.
The 6V6132 Cable Tie can be used to fasten tubing to the engine so it does not come in contact with hot surfaces. These ties are reusable. To loosen a tie, push back on the tang and pull OUT on the strap.
The SEES5677 Conversion Chart uses the SI unit kPa as its base unit of measurement. The chart has been rounded to the nearest practical measurement. It also allows conversion from kPa to psi, inHg, mmHg, cmHg, inH2O, ftH2O, cmH2O, atm, bar, and kg/cm2. The chart is printed on a material that is resistant to oil and water.
Optional Accessories
8T3047 Buttons (Finger Release)
8T3047 Buttons.
8T3047 Buttons installed on the tool group.
The 8T3047 Buttons (1) snap on the bulkhead fittings as shown. Installation of these buttons on the bulkhead fittings permits tubing removal without the need of a tool. To remove tubing from a fitting that is equipped with a button, press down on the button, then pull the tubing out of the fitting.
For permanent mounting, the buttons can be glued to the fittings.
8T0452 Manometer
The 8T0452 Manometer is used to read static pressure, vacuum, or differential pressure over a range of 50 cmH2O - 0 - 50cmH2O (for a total range of 100 cmH2O).
Specifications
Operating Temperature Range:
-1° C to 60° C (30° F to 140° F) for differential pressure gauges.
-18° C to 71° C (0° F to 160° F) for all other gauges.
Gauge Accuracy:
± 2 percent of full scale for differential pressure gauge. SAE Grade A (± 1.5 to 1 percent of full scale for all other gauges).
Vacuum and Pressure Ranges:
100 kPa (15 psi) for differential pressure gauge. Full scale for all other gauges (vacuum below lowest reading and pressures above full scale will destroy accuracy of all such gauges).
Operating Position:
Position has no effect on differential pressure gauge, if gauge has been mechanically adjusted to ZERO in the test position. On all other gauges, position has no effect on accuracy.
Pressure Media:
Differential pressure gauge - clean air and gases only (no liquids).
All other gauges - air, gases and liquids (oil, water, antifreeze, fuel, etc.).
| NOTICE |
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DO NOT use any acids or other highly corrosive liquids in the gauges. |
Size: 390 mm x 310 mm x 190 mm (15.4" x 12.2" x 7.5").
Weight: 6.8 Kg (13.1 lbs).
Description of Gauges
Differential Pressure Gauge
The 8T0839 Differential Pressure Gauge (1) can read the difference between two pressures. It has a range of 0 to 12 kPa (0 to 50 inH2O) and is accurate within ± .25 kPa (± 1.0 inH2O).
The 8T0839 Differential Pressure Gauge has two inlet ports. These ports are identified as follows:
- * One port is for the higher pressure and is identified by the word PRESSURE.
- * The other port is for the lower pressure and is identified by the word VACUUM. The gauge will indicate the difference between the two pressures.
If one port is left open to the atmosphere, the gauge can be used to measure the difference between atmospheric pressure and the test pressure.
If the PRESSURE port is connected and the VACUUM port left open, the gauge can be used to read a positive pressure (such as the exhaust back pressure caused by a muffler).
If the VACUUM port is connected and the PRESSURE port is left open to the atmosphere, a vacuum can be read (such as the inlet restriction through an air cleaner).
If both ports are connected to positive pressures (such as the gas delivery pressure and the inlet manifold pressure of a turbocharged natural gas engine), the gauge will read the difference between the two pressures.
This gauge has a zero adjusting screw. When necessary, adjust the screw so the gauge reads zero without any connections to the gauge fittings.
Pressure Gauges
The 8T0846 Pressure Gauge (2) can measure pressures of 0 to 1000 kPa (0 to 145 psi). Typical applications for this gauge are the measurement of oil pressure, and the cut-in and cut-out pressures on air compressors.
The 8T0848 Pressure Gauges (3) can be used to measure pressures of 0 to 400 kPa (0 to 58 psi).
Typical uses for these gauges are the measurement of fuel pressure, intake manifold pressure on turbocharged diesel engines, cooling system pressure and the power balancing of diesel engines in a multiple engine application.
The 1U5469 Pressure Gauge (4) is a pressure gauge that can be used to measure pressures of 0 to 200 kPa (0 to 60 inHg). Typical uses for this gauge are the measurement of intake manifold pressure on a turbocharged diesel engine. Valve (5) allows selection of one of the pressure ports (6 or 7).
Optional Compound Pressure Gauge
The 8T0840 Pressure Gauge is a compound pressure gauge that can be used to measure pressures of 0 to 100 kPa (0 to 30 inHg) and a vacuum of 0 to -100 kPa (0 to -30 inHg). Typical uses for this gauge are the measurement of intake manifold pressure on natural gas and gasoline engines, and the power balancing of natural gas engines in a multiple engine application.
The valve (part of the optional 1U5554 Panel Assembly) allows selection of one of the two pressure or vacuum ports that are also part of the 1U5554 Panel Assembly.
NOTE: The 8T0840, 8T0846, 8T0848 and 1U5469 Gauges are filled with glycerin lubricant. The lubricant completely surrounds all moving parts in the gauges. This glycerin lubricant greatly extends both the accuracy and the service life of the gauge. It also serves to dampen input pressure pulses.
Connection of Pressure Group to the Engine
1. The 8T0836 Elbow Fitting and 8T0837 Straight Connector are reusable tube fittings. They are described in the topic entitled Components of the 1U5470 Engine Pressure Group in this publication. These fittings can be installed into 1/8" NPT ports on all Caterpillar engines by using either a 7/16" box end wrench, or a 7/16" open end wrench.
The 8T0837 Straight Connector can be installed by using a 7/64" hex wrench if access to the port is limited.
2. To connect 8T0821 Tubing to any fitting, simply push the tubing all the way into the fitting. An internal O-ring seal, and an internal slotted collet mechanism within the bulkhead fitting, will lock on the outer diameter of the tubing to hold in the fitting. This provides an instant connection with total sealing.
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Be sure there is no pressure in the tubing before it is disconnected from the fitting. Hot oil can spray out and cause personal injury. |
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To remove the tubing from the fitting, press on the collet with the blade of a screwdriver, while pulling OUT on the tubing.
Use of Engine Pressure Group With Other Test Instruments
The 1U5470 Engine Pressure Group (1) should be used with the 6V3121 Multitach Group and 6V4060 Set Point Indicator (2), when checking engine performance. (The 6V4060 Set Point indicator is used with diesel engines only.)
Space has been provided inside the 8T0841 Case for storage of the 6V4060 Set Point Indicator and the necessary components of the 6V3121 Multitach Group [such as the 5P7366 Power Cable (3), 5P7362 Tach Cable (4), 6V2100 Multitach (5), 5P7360 Tach Generator (6), and 1P7446 Rack Contact Cable (7)].
For information on the use of the multitach group, see Special Instruction SEHS7807, entitled Using the 6V2100 and 6V3121 Multitach Group.
For information on the use of the set point indicator, see Special Instruction SEHS7931, entitled Using the 6V4060 Engine Set Point Indicator Group.
Use and Care of the 8T0452 Manometer
The 8T0452 Manometer can be used to measure the pressure of clean air and gases only. No liquid pressure media can be introduced into the manometer. To obtain accurate measurements, you must suspend the manometer in a vertical position.
NOTE: The manometer can not be used to measure pressures over 345 kPa (50 psi) or a vacuum greater than -67 kPa (-20 inHg). If the manometer is filled with water, it must be protected from freezing when temperatures are 0° C (32° F) or lower.
The 8T0452 Manometer is equipped with a flexible steel metric scale and a sliding ZERO adjustment. The manometer can be filled with either mercury or distilled water. A bottle of Fluorescein green color concentrated wetting agent is included with the unit.
NOTE: The manometer cannot be used with .826 specific gravity red gauge oil. Mercury or distilled water are the only permissible measuring media.
Filling
Use 0.946 L (1 quart) of distilled water, then add 22.2 mL (.75 oz) from a bottle of Dwyer A-126 Fluorescein green color concentrate. Remove a tubing connector from the manometer and pour the fluid in to mid-point level.
Shake the manometer to remove any air bubbles. Slide the scale so the zero mark is in alignment with the meniscus of the two columns of fluid.
For readings in centimeters of mercury, fill with 13.6 SP. Gr. triple distilled mercury. When the manometer is used with mercury, some discoloration of the vinyl tubing will normally occur.
Reading
Connect the manometer to the source of pressure, vacuum or differential pressure. When pressure is imposed, add the number of centimeters that one column travels UP, to the amount the other column travels DOWN. This is the pressure reading. If a reading is desired in other units of measure, use the conversion chart.
If one column should happen to travel further than the other column, due to minor variations in tube I.D. or to the pressure imposed, accuracy of the pressure reading thus obtained is not impaired.
The U-tube manometer is a primary measuring device indicating pressure by the difference in the height of two columns of fluid. The fact that one column travels further than the other does not affect the accuracy of the reading.
Both sides of the manometer must be at the same level and should read ZERO before pressure is measured. Pressure safety traps in the top of both manometer columns prevent the loss of fluid due to pressure surges, or pressures exceeding the pressure range of the instrument.
If the fluid in one side of the manometer is higher than the fluid in the other side, the pressure safety trap is probably air locked. Applying slight air pressure on one of the manometer input ports will usually release the air lock. If it does not, slide a small wire or other similar instrument into the input fitting. Gently push down on the metal trap to release the air lock. Remove the wire or instrument that was used to push down on the trap.
Cleaning
Cleaning can best be accomplished with a little pure soap and water. Avoid liquid soaps and solvents. Flush thoroughly with clear water to remove all soap. Dry completely before refilling with mercury.
When the manometer is not in use, put plugs in the 8T0837 Straight Connectors (inlet fittings). This will help in preventing a fluid loss during storage. Four plugs are included with each group.
Accuracy and Calibration of Gauges
8T0840, 8T0846, 8T0848, and 1U5469 Pressure Gauges
The 5P8558 Calibration Group and the 2D2825 Hydraulic Pump should be used to calibrate these gauges every six months, as shown in the Service Quality Guide, Form SEBF3500 (Bulletin No. TC-1). Use five test points as reference to check the calibration of each gauge. Calibration tolerances are as follows.
8T0839 Differential Pressure Gauge
1. Use a water manometer as shown in the illustration, with the procedure that follows, to check the calibration of the differential pressure gauge.
2. Use the zero adjusting screw, if necessary, to make 8T0839 Gauge (1) read ZERO without any connections.
3. Connect the PRESSURE port of 8T0839 Gauge (1) to the tubing of the manometer as shown.
4. Apply a light pressure, approximately 7 kPa (1 psi), to the manometer tubing, to cause the water column to read 70.3 cm (28") of water difference in pressure. The reading on the gauge should be 7.0 kPa ± .25 kPa (28 inH2O ± 1 inH2O).
5. Any gauges that are not within specification should be repaired or replaced.
Repair of the 1U5470 Engine Pressure Group
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A common cause for failure of the gauges is overpressure (pressure beyond the maximum on the gauge scale). Overpressure can destroy the gauge in three progressive steps:
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Failures caused by overpressure are not considered to be warranty, but, abuse by the operator. Repairs to such gauges are on a time and material basis. Examination of the mechanism by the manufacturer will indicate a past overpressure condition.
If it becomes necessary to repair the engine pressure group, do not send the instrument or the gauges to Caterpillar Inc., because this will only cause a delay. In the U.S.A. and Canada, the gauges can be returned for repair to the addresses shown below. Outside the U.S.A. and Canada, it is more economical to replace the gauges than to return them for a repair.
- * Return the 8T0839 Differential Pressure Gauge to:
Highway 212 at 12
Michigan City, IN 46360
Telephone: (219) 872-9141
Carrier - Oehler Co.16965 Vincennes Avenue
P.O. Box 40
South Holland, IL 60473
Telephone (312) 339-8200
Articles returned for warranty consideration or repair, should be packaged in a manner that will prevent damage in transit, and in accordance with the best commercial practice for fragile items. Instruments should not be shipped parcel post.
Procedure for the Update of a 6V3150 or 6V9450 Engine Pressure Group
To update either a 6V3150 or a 6V9450 Engine Pressure Group to make it comparable to the 1U5470 Engine Pressure Group, do one of the following: