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Introduction
Important Safety Information
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| Illustration 1 | g02139237 |
Think Safety | |
Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools to perform these functions properly.
Improper operation, lubrication, maintenance, or repair of this product can be dangerous and could result in injury or death.
Do not operate or perform any lubrication, maintenance, or repair on this product until you have read and understood the information.
Safety precautions and warnings are provided in this manual and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons.
The hazards are identified by the Safety Alert Symbol and followed by a Signal Word such as "DANGER", "WARNING", or "CAUTION". The Safety Alert "WARNING" label is shown below.
A non-exhaustive list of operations that may cause product damage are identified by "NOTICE" labels on the product and in this publication.
Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. The warnings in this publication and on the product are, therefore, not all inclusive. If a tool, procedure, work method, or operating technique is not recommended by Caterpillar, the operator must be sure that the procedure is safe. The operator must also be sure that the product will not be damaged or made unsafe by any unspecified procedures.
The information, specifications, and illustrations in this publication are based on information that was available at the time that the publication was written. The specifications, torques, pressures, measurements, adjustments, illustrations, and other items can change at any time. These changes can affect the service that is given to the product. Obtain the complete and most current information before you start any job.
When replacement parts are required for this product, Caterpillar recommends using Cat replacement parts or parts with equivalent specifications including, but not limited to, physical dimensions, type, strength, and material.
Literature Information
This manual contains safety information, operation instructions and maintenance information and should be stored with the tool group.
Some photographs or illustrations in this publication may show details that can be different from your service tool. Guards and covers might have been removed for illustrative purposes.
Continuing improvement and advancement of product design might have caused changes to your service tool, which are not included in this publication.
Whenever a question arises regarding your service tool or this publication, consult Dealer Service Tools (DST) for the latest available information.
Safety Section
The Safety section lists basic safety precautions.
Read and understand the basic precautions listed in the Safety section before operating or performing maintenance and repair on this service tool.
General Information Section
The General Information section describes tooling functions and features. The section provides useful information on individual parts, additional tooling, and resources.
Operation Section
The Operation section is a reference for the new operator and a refresher for the experienced operator.
Photographs and illustrations guide the operator through correct procedures for using the tool group.
Operating techniques outlined in this publication are basic. Skill and techniques develop as the operator gains knowledge of the service tool and tool capabilities.
Maintenance Section
The Maintenance section is a guide to tool inspection, cleaning, storage, and tool disposal.
Safety Section
Safety Icon Nomenclature
Personal Protection/Important Information
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| Illustration 2 | g02140175 |
Personal Protection/Important Information | |
Prohibited Action
| Do not drill |
| Do not weld |
Hazard Avoidance
| Crushing hazard |
| Electrical hazard |
| Pinch point |
| Safety alert symbol |
General Information Section
Introduction
The 1U-8860 Large Engine Blowby Pickup Group is an optional pickup for use with the 8T-2701 Blowby/Air Flow Indicator.
It contains a large 38 mm (1.5 inch) I.D. pickup which allows it to be used on large engines without increasing the crankcase pressure.
It is designed to monitor the blowby volume on Cat 3500, 3600, and D300 series engines, as well as competitive large engines.
The range of this pickup is 94 to 1888 L/min (200 to 4000 cfh).
Due to the all metal construction and large size, the 1U-8860 Large Engine Blowby is suitable for permanent installation on engines so blowby can be continuously monitored. The Blowby is useful for dynamometer rooms or marine or gen set installations.
When connected to the 8T-2701 Blowby/Air Flow Indicator, a digital display provides the blowby value (volume of exhaust gas escaping to the crankcase). This blowby value can be used as an indication of engine condition.
However, the Blowby should not be used as a stand-alone "good/bad" indicator for engine overhaul. If an engine is in need of maintenance, the Blowby can be used as a signal that engine conditions are present, such as oil consumption, low power, hard starting, and excessive fuel consumption.
The large blowby meter has no moving parts. An ultrasonic sound vortex shedding principle is used to measure the air flow. This principle makes the pickup reliable and virtually maintenance free.
This unit will be used to replace the smaller 8T-2685 Pickup for the measurement of the 3500 series, 3600 series, and the ACERT engines. The 8T-2685 Pickup can be used on these engines, but only for a short duration test since the 50.8 mm (2 inch) engine breather tube is reduced to 15.7 mm (.63 inch) during the test. The 8T-2701 Blowby/Air Flow Indicator will be used with the larger probe, however a 1U-8863 Conversion Group must be installed to make it accurate. Refer to Installation of the 1U-8863 Conversion Group .
Adaptability
When used with the 8T-2701 Indicator, the 1U-8860 Pickup can be used to measure the blowby on any engine within the blowby range of 94 to 1888 L/min (200 to 4000 cfh). This range includes the larger Cat D300 Engines, the 3500 series, 3600 series, and the ACERT engines.
Smaller D300 and 3500 engines may not have enough blowby at idle, or partial load to give a reading when the engines are in good condition. Therefore, the indicator display will read zero until the engine is loaded.
Additional Contact Information
For additional product support questions concerning this tool, contact the Cat Dealer Service Tools Hotline at:
USA: 1-800-542-8665, Option 1 International: 1-309-578-7372 E-mail: dealerservicetool_hotline@cat.comNomenclature
1U-8860 Large Engine Blowby Pickup Group
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| Illustration 3 | g02633479 |
(1) 6V-7145 Case NEEG2332 Decal ( 1U-8860 Group ) (2) 1U-8861 Pickup-Large Engine Blowby NEEG2331 Decal ( 1U-8861 ) (3) 1U-8863 Conversion Group - Large Pickup (4) 9M-0164 Hose Clamp - Worm Drive 12.7 mm x 63.5 mm Dia. (.50 in x 2.50 inch Dia.) (2 required). (5) 1U-8868 Hose, Rubber 57 mm ID. x 305 mm Dia. (2.3 in ID. x 12.0 in) (Goodyear Part No. 56036) (6) SEHS8984 Special Instruction (not shown). | |
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| Illustration 4 | g02633736 |
(1) 8T-2701 Blowby/Airflow Indicator (2) 8T-5297 Cable - Blowby Pickup 915 mm (3 ft) (3) 6V-2198 Cable - Blowby Pickup 5486 mm (18 ft) (4) 5P-7366 Cable - Indicator Power 5486 mm (18 ft) (5) 8T-5268 Converter , 110/120 V AC, 50/60 Hz for powering 8T-2701 Indicator . Supplies 11 to 20 V DC at 0.3 Amp. (Max. Current) (6) 8T-2700 Blowby/Airflow Indicator Group for Small Engines , Complete (not shown). | |
Specifications
Note: Specifications are for use with the 8T-2701 Indicator.
| Specifications for use with the 8T-2701 Indicator | |
| Power | External: 11 to 40 Volts DC at .007 Ampere |
| Blowby Measuring Range | 8 to 472 L/min 18 to 1000 cubic foot/hr 43 to 2390 M/min 141 to 7843 ft/min |
| Accuracy | ± 5% of the reading |
| Resolution | Blowby: 1 L/min (1 cubic foot/min) Airflow: 1 M/min (1 ft/min) |
| Readout Update and Averaging Rate: | Normal Rate: Data measured 2 1/2 times/second. The LCD is updated every second. Medium Rate: Data measured 2 1/2 times/second. The LCD is updated every five seconds. Slow Rate: Data measured 2 1/2 times/second. The LCD is updated every 10 seconds. |
| Operating Temperature | -18 to 60°C (0 to 140°F) |
| Storage Temperature | -40 to 100°C (-40 to 212°F) |
| Battery Life | Alkaline battery: 30 continuous hours (nominal) or up to 90 hours intermittent. |
| Size | 190 mm (7.5 inch) x 112 mm (4.4 inch) x 40 mm (1.6 inch) |
| Weight | 0.567 kg (1.25 lb) |
| Power Input Connector | Connection for external 11 to 40 Volt DC power source. This connection is not required if a good 9 Volt battery is installed in the indicator. |
| 285-0900 Small Engine Blowby Tool Group Specifications | |
| Blowby Range Resolution | 8 to 472 L/min (18 to 1000 ft/hr) 1 L/min (1 cubic foot/hr) |
| Airflow Range Resolution | 43 to 2390 M/min (141 to 7843 ft/min) 1 M/min (1 ft/min) |
| Output Range Resolution | 0 to 1700 mV 1 L/min (1 cubic foot/hr) at 0.605 mV |
| Analog to Digital (A/D) Resolution | 0.488 mV |
| Probe Error % | ±5 % of reading |
| 285-0901 Large Engine Blowby Tool Group Specifications | |
| Blowby Range Resolution | 94 to 1888 L/min (18 to 1000 ft/hr) 1 L/min (1 cubic foot/hr) |
| Airflow Range Resolution | 83 to 1656 M/min (272 to 5436 ft/min) 1 M/min (1 ft/min) |
| Output Range Resolution | 0 to 680 m/V (1 L/min) 1 cubic foot/hr () at 0.355 mV |
| Analog to Digital (A/D) Resolution | 0.488 m/V |
| Probe Error % | ±10 % of reading |
Part Numbers
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| Illustration 5 | g02661757 |
285-0900 Blowby Tool Group (Small Engine) | |
| 285-0900 Blowby Tool Group (Small Engine) | ||
| Qty | Part No. | Description |
| *1 | 8T-2685 | Blowby Pickup (Small Engine 1,000 CFH Max) |
| 1 | 285-0903 | Cable Assembly |
(*) Part of 8T-2700 Airflow/Blowby Group This group also includes bushings, hoses, and clamps.
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| Illustration 6 | g02661857 |
285-0901 Blowby Tool Group (Large Engine) | |
| 285-0901 Blowby Tool Group (Large Engine) | ||
| Qty | Part No. | Description |
| 1 | 1U-8861 | Blowby Pickup (Large Engine 4,000 CFH Max) |
| 1 | 9M-0164 | Clamp |
| 1 | 1U-8868 | Blowby Hose (Large Engine) |
Operation Section
Installation of the 1U-8863 Conversion Group
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| Illustration 7 | g02635362 |
A 1U-8863 Blowby V1.20 Conversion Group integrated circuit (1) is packaged with the 1U-8860 Large Engine Blowby Pickup Group . This integrated circuit contains the program which makes the large pickup readings accurate.
The integrated circuit must be installed in the 8T-2701 Blowby/Air Flow Indicator . Once the indicator is completed, the 8T-2701 Indicator will be accurate for both the large Blowby Pickup and the Small Blowby Pickup.
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| Illustration 8 | g02637398 |
The 1U-8863 Conversion Group (1) is the small plastic box packed in the front storage area of the large pickup case. Open the small plastic case to identify the conversion group integrated circuit memory, but DO NOT remove the indicator at this time. The indicator should be marked 1U-8863 Blowby Gp. V1.20.
The following instructions are used to install the integrated circuit in the 8T-2701 Indicator. The Indicator is used with the large Blowby Probe.
| NOTICE |
|---|
The 1U-8863 Conversion Group integrated circuit memory may be damaged by static electricity discharge. DO NOT handle in a carpeted, dry area where static electricity may be present. |
Installation Instructions
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| Illustration 9 | g02637601 |
- Remove six screws (2) from the rear cover and remove cover (3) .
- Remove battery (4) from the holder. Use a small screwdriver to pry the old Blowby V1.19 integrated circuit memory from the socket and remove.
Note: The old Blowby V1.19 is to be replaced and may be discarded.
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| Illustration 10 | g02637777 |
- Remove the 1U-8863 Blowby Group V1.20 Integrated Circuit (1) from the protective plastic case. Carefully install the circuit into the socket next to the battery holder (5) .
Note: The notch in the end of item (1) must be at the battery holder end of the socket.
Note: Check to make sure all of the pins are in the socket and are not bent over or under.
Note: The integrated circuit may not have as many pins as the socket has holes. When this occurs, install the integrated circuit as far as it will go towards the edge of the printed circuit board. Make sure that the empty socket holes are on the battery holder end of the socket.
- Install a new 9 V battery in the battery holder.
Note: Be sure that the + (positive) terminal on the battery is on the + (positive) red terminal on the holder.
- Install rear cover (2) and six screws (3) .
- Check the operation of the 8T-2701 Indicator with the large blowby probe as described later.
- If the indicator works properly, it is ready for use.
Blowby Test Procedure
- Locate the crankcase breathers (1) on the engine. The engine may have more than one crankcase breather. If there is more than one, the blowby coming from all of the crankcase breathers must be measured at the same time.
Most engine installations will already have the breathers connected together with tubing (2). The pickup can then be installed after the point where they come together (3). If the breathers are not already connected, they may be connected with hoses or by temporarily plugging all but one breather for a short period during a temporary test.
If the pickup installation is to be permanent, the breathers must be connected together with adequate sized tubing to prevent excessive crankcase pressure.
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| Illustration 11 | g02638096 |
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| Illustration 12 | g02638136 |
- The 1U-8861 Large Engine Blowby Pickup (4) can be installed directly into the breather flexible fitting (5). The fitting is used on some Cat engines, provided the fitting is the correct size. This installation is suitable for a temporary check of blowby.
Be sure to install the pickup with the arrow pointing away from the engine in the direction of blowby air flow. Secure the pickup with a hose clamp. Since the pickup is heavy, it may be necessary to secure the pickup to keep it from moving during the operation.
- For installation to the end of a metal blowby tube, a rubber hose (6) is included in the group. It will fit most tubes which have close to a 50 mm (2.0 inch) diameter. Secure the hose with clamps (7) .
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| Illustration 13 | g02638145 |
- Attach an 8T-5297 Cable or a 6V-2198 Cable to the connector on the pickup and the other end to the pickup connector on the 8T-2701 Indicator . The installation is complete.
Measuring Blowby
Note: The large blowby pickup is sensitive to excessive high frequency noise and air currents entering the open end of the pickup. To prevent inaccurate readings, keep the pickup outlet as far away from the engine turbocharger as possible, and away from the fan or any wind blowing past the open end of the pickup.
If the pickup must be placed close to the engine or in the air stream, use a length of rubber hose to extend the outlet away from the source of high frequency noise or air stream.
- Start and run the engine until normal operating temperature is reached.
- Blowby readings should be taken with the engine at full rpm. Readings may be taken at no load or full load, but the engine must be loaded to measure the maximum blowby output of the engine.
On smaller 3500 engines, the indicator may show zero until the engine is loaded since the blowby is below the minimum rating of the pickup.
Analyzing Results
Note: Blowby should be used as a guide only to indicate engine condition and not as an absolute good/bad indicator. DO NOT use the blowby data alone to determine if the engine should be rebuilt. If the blowby value is high, check the other indicators such as oil consumption, low power, etc.
Cat recommends checking the blowby by the same method for better comparison of future tests. Record the blowby rate and the load on the engine during the test for later reference.
New engines initially need to be checked for blowby and thereafter during all maintenance checks.
As the engine rings and cylinder walls wear, the blowby will gradually increase. The blowby on a worn engine will be considerably higher than for a new engine. By keeping a record of the results, a gradual increase in the amount of blowby will be noted until the amount of blowby has become excessive.
High oil consumption and other problems associated with high blowby, will not be experienced until the blowby is considerably higher than the values shown in the chart. (Approximately two times or more.)
After a new engine is used for a short time, the blowby can decrease as the rings are seated. A newly rebuilt engine can have a high blowby rate due to the rings not being properly seated, or worn parts that were not changed (valve guides).
Checking the Operation of the Large Blowby Pickup
Obtain the 8T-2700 Blowby/Air Flow Group which will be used with the large probe. Perform the check-out instructions to be sure that the probe is working properly before proceeding.
If the 8T-2685 Pickup is not available, only perform the following tests:
Note: The components required for the following test are the 8T-2701 Indicator, the 8T-5297 the 6V-2198 Cable and the 1U-8861 Pickup .
- Connect the 1U-8861 Pickup to the indicator with the cable.
- Press the ON Switch, then the FT/MIN, ACTUAL, and the NORM RATE switches. An arrow should appear on the display and point to the same name as the switch pressed. The display should read zero.
- Blow into the pickup in the direction of the arrow on the side. Observe the reading on the indicator display. The display should read approximately 263 m/min (862 ft/min) to 439 m/min (1439 ft/min) 862 to 1439 ft/min, depending on how hard you blow.
- Press the M/MIN switch and the arrow should point to M/MIN. Blow into the pickup again and the indicator should read approximately 262 to 438 M/MIN, depending on how hard you blow.
- Press the Cubic Foot/HR switch and the arrow should point to the Cubic Foot/HR. Blow into the pickup again and the indicator should read approximately 635 to 1059 Cubic Foot/HR, depending on how hard you blow.
- Press the OFF switch and the display should be blank.
The test is complete for the 1U-8863 Pickup.
Repair Information
If the large blowby probe does not operate correctly, use the procedure, "Checking Operations of the Pickup." Determine if the problem is in the pickup or the indicator.
If the pickup is found to be faulty, contact Cat Dealer Service Tools for service or warranty information.
Units less than one year old will be repaired under warranty (except for abuse). Cost of out-of-warranty repairs will be charged to the owner.
Note: The 8T-2700 and 8T-2701 are no longer in production. They have been replaced by the 348-5430 Multi-Tool (NEHS1087).
Note: The Small Blowby probe and adapters are available under part number 285-0900. The large Blowby probe is available under part number 285-0901.