1986/01/01 Caterpillar


How To Use Temperature And Pressure Probes With Self-Sealing Probe Adapter Groups

Usage:


Self sealing probe adapters are designed to be used in situations that require the temperature of a captive fluid (gas or liquid) to be measured without stopping the machine or draining the system. The self sealing probe adapters are available in three configurations: 5P2720-1/8"-27 NPT, 5P2725-1/4"-18 NPT and 5P3591-9/16" straight thread with O-ring seal.

The probe adapters are to be used with 1/8"diameter probes only. Some earlier probes had a 3/16" diameter shoulder near the thread area. These probes should not be installed into a probe adapter. The probe adapters are designed to be used at a temperature NOT to exceed 130 °C (266°F) and at a pressure NOT to exceed 3100 kPa (450 psi). The probe MUST be clean, smooth and lubricated with a petroleum jelly prior to being inserted into the probe adapter. It is not generally necessary to tighten the probe with a wrench. However, if a wrench is used, tighten only enough to hold the probe in place. The seal takes place within the adapter not at the probe threads.

To help ensure that the self sealing probe adapter seals when a probe is being installed or removed, use the following procedure.

Installation Of Self-sealing Probe Adapter

1. The earlier probe adapter had flats on the seal retainer. The current seal retainer does NOT have flats on it. The flats were removed to help prevent accidental removal of the seal retainer. The seal retainer is installed during assembly with a thread lock material and tightened to a specific torque. Prior to installation, check probe adapters for a loose seal retainer by removing the plug. The seal retainer should not move as the plug is removed. DO NOT use adapters that have a loose retainer. Do not attempt to retighten a seal retainer that has come loose because the seal between the seal retainer and bladder will be damaged.

2. The seal bladder is punctured during manufacturing with a sharp instrument. Make sure that the seal bladder has been prepunctured before installation by lubricating a clean, smooth probe and inserting the probe into the adapter. Look at the bladder while inserting the probe. A prepunctured bladder will have an obvious opening on the surface and very little force will be required to insert the probe through the bladder. DO NOT use an adapter that has NOT been prepunctured. Do not attempt to puncture a bladder that has not been prepunctured. To do so may damage the seal between the seal retainer and the bladder and also tear the bladder which will cause the adapter to leak when it is installed.

3. Remove the probe and reinstall the plug. Tighten the plug enough to hold it in place.

4. Install the probe adapter on the machine. This should be done while the machine is shut down, cool and the system is relieved of any pressure. It may be necessary to drain liquids prior to drilling and tapping a point of access.

Probe Installation

1. With the machine either operating or shut down, remove the cap slowly. The seal retainer should not move and there should be no leakage. If the seal retainer moves or there is leakage, retighten the plug. Do NOT use the adapter.

2. Lubricate a clean, smooth, 1/8" diameter probe with petroleum jelly. Insert the probe straight into the adapter. If the probe is at an angle, it may cause the seal to leak as the probe is inserted.

3. Tighten the probe hand tight. The bladder seals against the probe not at the threads, therefore, excessive torque is not required.

Probe Removal

1. Watch the seal retainer while loosening the probe. The seal retainer should not rotate. If the seal retainer should rotate or if there is evidence of leakage under pressure, do NOT remove the probe. Retighten the probe and leave it in place until the machine can be shut down and the probe can be removed under low temperature and pressure conditions.

2. If the seal retainer does not rotate and there is no evidence of leakage under pressure (there may be a small amount of seepage), pull the probe straight out quickly. After the probe is removed, the seal may seep slightly if the pressure in the system is very low 0 to 35 kPa (0 to 5 psi). The plug should ALWAYS be installed immediately after removing the probe. The plug should be installed with a very moderate torque. Tightening the plug to tightly may cause the seal retainer to loosen when the plug is removed the next time.

Do NOT use probe adapters that have not been prepunctured or that have loose seal retainers. Return these adapters for inspection to one of the following addresses.

U.S. MAIL
Caterpillar Service Technology Group
LD 180
600 West Washington
E. Peoria, IL 61630

UPS
Caterpillar Service Technology Group
LD 180
330 S.W. Adams
Peoria, IL 61602

Caterpillar Information System:

1986/01/01 Oil Total Base Number (TBN) Test Kit Available
1986/01/01 Fuel Sulfur Analyzer Available
1986/01/01 Put Grease On Front Crankshaft Seal Before Installing The Crankshaft Pulley And Damper
1986/01/01 New Service Tools Available
1985/12/01 Later 3406B And 3408B Truck Engines Have Higher Minimum Coolant Temperatures
1985/12/01 Gasket Leakage On Aftermarket Fuel Filters
1985/12/01 New, Tougher Gasket Used Between Block And Front Housing
1985/12/01 Use Care When Handling Turbocharger Compressor Wheels
1985/12/01 Canister Size Of Coolant Conditioner Element Has Changed
1985/12/01 New Ratchet Wrenches Available For Tube Fittings
1985/12/01 Service Life Of Oem Primary Fuel Filters
1985/12/01 New Fuel Ratio Control Group Used On Engines Equipped With New Scroll Fuel System
1986/02/01 High Silicates In Antifreeze
1986/02/01 New 8T2998 Lubricant Available
1986/02/01 Longer Bolts Used In Turbocharger Air Lines Groups
1986/02/01 Truck Engine Performance Checklist Available For North American Dealers
1986/02/01 New Cylinder Liner Available
1986/02/01 Special Instructions Packaged With Turbocharger Cartridge Repair Kits May Be Incorrect
1986/02/01 Incorrect Air Compressor Installation Can Cause An Early Failure
1986/02/01 Attention "New" Caterpillar BrakeSaver Owners!
1986/03/01 Screens Added To Inlet Air Manifolds
1986/03/01 Nylon Seals Used On Lockwire To Seal Critical Areas; Parts Service Seals Available For NACD Dealers
1986/03/01 Improved Cylinder Head Gasket
1986/03/01 Stronger Oil Pan Used
Back to top
The names Caterpillar, John Deere, JD, JCB, Hyundai or any other original equipment manufacturers are registered trademarks of the respective original equipment manufacturers. All names, descriptions, numbers and symbols are used for reference purposes only.
CH-Part.com is in no way associated with any of the manufacturers we have listed. All manufacturer's names and descriptions are for reference only.