Alternative Fuel Systems (2004) Inc.

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Falcon Natural Gas Regulator Installation Guidelines Falcon Regulator Mounting The installation must be made in accordance with the code of the authority having jurisdiction in your area, or in the

4 or the American Standard for Compressed Natural Gas (CNG) Vehicular Fuel Systems NFPA 52. Determine the proper location using the following criteria: Locate the regulator in the engine compartment.

1 Falcon Natural Gas Regulator Installation Guidelines Falcon Regulator Mounting The installation must be made in accordance with the code of the authority having jurisdiction in your area, or in the absence of a local code, in accordance with the current edition of the Canadian Standard for Natural Gas Vehicles Installation Code CAN/CGA-B149.4 or the American Standard for Compressed Natural Gas (CNG) Vehicular Fuel Systems NFPA 52. Determine the proper location using the following criteria: Locate the regulator in the engine compartment. Locate the regulator for ready access for installation and maintenance. Do not locate the regulator on the engine block. Do not locate the regulator within 12 cm (5 in.) of an exhaust pipe or exhaust manifold. Do not locate the regulator within 5 cm (2 in.) of moving parts (e.g. V-belts, pulleys, etc.) Do not locate the regulator so that it interferes with OEM mechanical operation or where mechanical operation endangers the regulator (e.g. engine rock, hood closing). Figure 1: Falcon regulator mounting orientation limits - 1 -

2 Innovative Environmental Technologies Do not locate in the splash path. Do not locate on the frontal sheet metal. Do not locate on the radiator tank. Do not locate in areas that interfere with routine service operations (e.g. checking or adding oil, transmission fluid etc.) Orient the regulator within a 180º span as shown in Figure 1. Installer-made brackets are acceptable if they meet the above criteria. Caution: The atmospheric reference ports located on the side of the regulator and on the first stage tower must remain free of obstruction and shall be protected from the ingress of soil, debris and fluids. You may need to fabricate a bracket to mount the regulator. Paint it to protect it from corrosion, and use corrosion-resistant fasteners. Ensure that the regulator body is not stressed when the regulator is mounted to the bracket, and make sure the installation is rigid with no parts rubbing against each other. Use a minimum of 2 mounting holes though depending on your application, more may be required. Coolant and Gas Connections Coolant Connections The Falcon regulator requires heat to keep it from freezing up as the CNG expands from high pressure to a lower pressure usable in the engine control system. This heat is supplied by hot engine coolant that circulates through a coolant plate attached at the base of the regulator. Caution: The Falcon regulator coolant plate is a nonserviceable item. Removal of the coolant plate (even if the coolant plate is subsequently replaced after removal) or tampering with the coolant plate installation in any way can result in damage to the Falcon regulator. This damage is not covered under warranty. Vehicles have varying coolant hose routings and functions. The Falcon regulator coolant ports are connected in parallel with an existing engine coolant circuit as shown in Figure 3. Vehicles operating in low-temperature environments (where seasonal temperatures can drop below 25 C) require the use of a circulating-style block heater connected so as to circulate coolant through the Falcon regulator as well as the engine block. High CNG flow through the regulator under cold conditions, coupled with low coolant flow could result in premature wear of internal components. This condition is intensified by a de-pressurized regulator outlet line; see page 8 for lowpressure shut-off requirements. You must select coolant hoses using the following guidelines: There must be coolant flowing in the lines at all times when the engine is running. Some coolant lines only conduct coolant after or before the engine thermostat opens. The coolant lines chosen must have enough pressure drop across them to flow coolant through the regulator even at idle. The regulator will divert some coolant flow away from the original function of the hoses. Ensure that this is acceptable and that the installation of the regulator does not compromise a critical vehicle function such as transmission oil cooling. Do not select a coolant return point that diverts the coolant directly to the radiator, bypassing the engine thermostat. This will provide cooling at all times and may prevent the engine from reaching its normal operating temperature. Caution: Do not plumb the Falcon regulator in series with a coolant line. The relatively high restriction of the regulator, and the high coolant pump output on some engines at high speed will cause a large pressure drop across the regulator. This will impede the original function of the coolant circuit and the fast-flowing coolant may induce erosion and cavitation in the regulator heat transfer passages. Figure 2: Falcon regulator ports - 2 -

3 Falcon Natural Gas Regulator Tip: Vehicle interior heating hoses are often a good choice for regulator heating. They are large diameter and high flow, and the diverted coolant does not significantly affect heat output. When you have chosen the coolant tap locations according to the above criteria, install the coolant plumbing as directed below. Coolant tees, hose, and clamps can be supplied by AFS. 1. Drain the coolant system or clamp hoses to be cut. 2. Cut the original coolant hoses (e.g. heater hoses) and insert tees. 3. Use appropriate coolant hose and cut to proper length for routing from tee to regulator. 4. Attach using hose barb connectors that thread into the regulator. 5. Ensure that the direction of flow is correct. See Figure 3 for correct flow. 6. Secure all coolant hoses to fittings and tees with hose clamps. Do not over-tighten clamps. 7. Refill the coolant system or unclamp hoses. Check and eliminate any coolant leaks. Caution: Be careful running the engine to check for leaks. If the coolant has been drained, air pockets may prevent the coolant pump from properly circulating the coolant, resulting in possible overheating and engine damage. Always check the coolant level (after the engine has cooled down) to ensure that the level is correct. Improper coolant connections are a primary cause of premature regulator failure. Inadequate coolant flow may cause internal ice-up, blocking gas flow. It may also cause extremely cold internal temperatures which will damage elastomeric and metallic components. The most common deficiency is inadequate coolant flow during certain, often unusual, operating conditions. For example: Cold start, low idle speed: the coolant pump is operating very slowly. Combined with increased coolant viscosity, flow may stop in the regulator circuit. In this condition, further heat is drawn out of the coolant plate until the coolant freezes, stopping all flow even when engine speed is increased. Regulator internal temperatures are cold enough to damage elastomeric and metallic components. Long, small-diameter coolant hoses: the surface tension of long hoses may overcome the low differential pressure created by the coolant pump, especially in cold or low engine speed conditions. Variable-flow coolant hoses: some engine coolant hoses have variable flow, depending on thermostat position -- many thermostats cause one coolant flow path when the engine is cool, another at normal operation temperatures, and yet another if the engine is running to warm. Coolant flow through the regulator must remain substantial under all of these conditions. Other conditions which may vary coolant flow include heater and air-conditioner settings and auxiliary cooler thermostat operation. Figure 3: Falcon regulator coolant flow - 3 -

4 Innovative Environmental Technologies It is the responsibility of the vehicle application engineer to ensure flow is maintained under all conditions. A good guideline is that sufficient flow always exists to maintain coolant temperature exiting the regulator coolant plate within 3 C (5 F) of engine water jacket temperature (not necessarily coolant plate inlet temperature). AFS recommends that these temperatures be logged in varied onroad operation to verify compliance. Pressure Relief Valve Hose Connection In the case of a regulator malfunction, an internal pressure relief valve (PRV) will be activated, releasing built-up CNG pressure for safety and protecting other parts of the fuel system. The PRV is a large valve intended to reduce pressure as quickly as possible. In the event of a PRV release, a large amount of high pressure CNG may flow from the PRV. Selection and installation of a PRV hose is subject to the following criteria: Selected hose and clamp must be able to withstand large pulses of high pressure CNG at a high flow rate for short periods of time. Even though the hose is open to atmosphere, internal pressure during a discharge can be over 2500 kpa (350 psi). An incorrectly matched hose could rupture or burst, causing natural gas build-up in the engine compartment. Ensure that the PRV hose end is free to atmosphere and located to prevent water or contaminants from entering the hose. In the event of a PRV release, any blockage (including ice or snow) would impair the PRV s effectiveness. Optimize for the shortest and simplest routing without conflicting with other criteria. Use routing that will not cause or allow the hose to kink. Do not route the hose within 15 cm (6 in.) of any exhaust manifold, pipe or catalyst. Do not route the hose within 8 cm (3 in.) of moving vehicle parts (e.g. fan belts). Do not route the hose against sharp edges, or in an area where the hose could rub or vibrate against vehicle parts. Secure the hose with clamps, strong clips and/or ties, ensuring that they do not deform the hose, which would restrict flow. Poor securing procedure could allow the hose to break loose and discharge gas into an unsafe location. Caution: Ensure that the open end of the PRV hose would discharge CNG to a safe location in the event of a discharge. The discharge point must be outboard of the vehicle perimeter, where discharged gas would dissipate freely without creating a safety hazard. Natural gas rises: do not choose a location that would allow the gas to collect under body or chassis components. Table 1: Falcon regulator torque values Gas Inlet (-6, 9/16"-18, SAE J1926) 30±3 N m 22±2 ft lb Gas Outlet (-8, 3/4"-16, SAE J1926) 35±4 N m 26±3 ft lb Coolant Plate Inlet/Outlet (M10x1, SAE J2244) 8±1 N m 6±1 ft lb PRV Outlet (1 1/16" -16 SAE J512) 12±1 N m 9±1 ft lb Mounting Screws (M8x1.25) 15±2 N m 11±1 ft lb Mounting Screws (M6x1) 13±2 N m 10±1 ft lb Mounting Screws (1/4"-20 UNC) 13±2 N m 10±1 ft lb - 4 -

Falcon Natural Gas Regulator CNG Supply Tubing Connection The high pressure tubing connection to the regulator uses tube compression fittings.

5 Falcon Natural Gas Regulator CNG Supply Tubing Connection The high pressure tubing connection to the regulator uses tube compression fittings. Depending on the application, your system will use 6 mm, 8 mm, 10 mm, ¼ in., or ⅜ in. tubing diameter fittings. Ensure that the fitting diameter matches the tubing diameter 6 mm and ¼ in. especially are very close in size and must not be mixed. Note the following: Ream and clean the tube end carefully. Blow out the tubing with compressed air before connecting, to eliminate all debris. Ensure that stresses are relieved in the tubing area and that the tubing will not be flexed, stressed or abraded in any operating condition. Caution: Do not apply a clamping or restraining force to the top of the regulator as this can result in damage to internal components. Such force may come from placing the regulator in a vice or other clamping device when installing fittings and fasteners. This damage is not covered under warranty. Depressurisation Procedure Caution: The depressurisation procedure must be carried out in the order presented. Failure to follow the instructions can result in damage to the Falcon regulator. This damage is not covered under warranty. 1. Shut off the gas supply to the regulator using a manual service valve located upstream of the regulator or by shutting off the valves on all pressure cylinders supplying the regulator. In the case of automatic shut-off valves (electrical or otherwise): physically disconnect the power source to each automatic shut-off valve to prevent unintended operation of the valves. 2. Disconnect the electrical connection to the regulator. 3. Slowly release the pressure downstream of the regulator (gas outlet side) in accordance with the vehicle service procedures. 4. Once step 3 is completed, slowly release the pressure upstream of the regulator (gas inlet side) in accordance with the vehicle service procedures. 5. The regulator can now be removed from service. Caution: Steps 3 and 4 must be executed in the order presented. Failure to follow this sequence can result in damage to the Falcon regulator. This damage is not covered under warranty. Figure 4: Falcon regulator clamping - 5 -

6 Innovative Environmental Technologies Wiring Pinout When connecting the Falcon regulator, use the following pinout to ensure your system is compatible with the Falcon regulator: A Fuel Pressure Sensor Signal: This is the output signal from the fuel pressure sensor. The Signal will be 0 5 V, refer to Figure 5 for the output voltage. D Fuel Pressure Sensor Ground: This must be connected to an instrument grade ground. This sensor is a solid-state device and must be treated as such. Any voltage spikes on the ground or power wires can damage the sensor. E Shut-off Solenoid Power: Check your regulator for shut-off solenoid voltage. It will be either 12 or 24 V. F Shut-off Solenoid Ground: This can be connected directly to or switched to a reliable engine ground. H Fuel Pressure Sensor Power: The Fuel Pressure Sensor must be powered by a conditioned instrumentgrade 5 V, 6.5 ma power supply (any common automotive ECM 5 V power supply). Voltage spikes on the ground or power wires can damage the sensor. Shut-off solenoid connections: The shut-off solenoid must be connected to a switched power or ground source. The solenoid should be opened (switched on) only when fuel is required (during engine running and cranking). Routing a Wire Harness When routing a wire harness, here are some rules to follow: Do not route near hot spots such as exhaust components. Do not route near belts, pulleys, fans, etc. Any rotating component can be a hazard on its own and may send debris flying towards nearby components. Do not route wiring together with high-tension ignition coil leads. Caution: Do NOT route any wiring harness leads within 20 cm (7 in.) of an ignition lead. Doing so can cause radio frequency interference in the harness which could damage electronic components. Do not route wire next to sharp edges such as are found on some sheet metal brackets and body panels. Do not route wire in any area where it may be subject to chemical splash or dripping. Some chemicals, particularly power steering fluid can damage the insulation on the wires. Always fasten wires down with tie straps and cable clamps. Do not allow wires to hang loose Falcon Regulator Fuel Pressure Output Voltage 5 4 Output Voltage (V) Pressure (MPa) Figure 5: Fuel pressure sensor output voltage - 6 -

7 Falcon Natural Gas Regulator CNG Regulator Connector (Device Side) CNG Regulator Connector (Harness Side) H G F E A B C D E F G H D C B A CNG Cylinder Pressure Sensor BLK BLU E F WHT G WHT RED H D C B A E F G H D C B A BLK BLU WHT WHT WHT/RED D - FPS Ground E - Shut-Off Solenoid Power (+12 or +24 V) G - Shut-Off Solenoid Ground A - FPS Signal Out (0-5 V) H - FPS Power (+5 V) Shut-Off Solenoid Note: Colors may vary from illustration Figure 6: Falcon regulator connector pinout for the standard 8-pin Delphi 150 series connector. The Falcon regulator can be supplied with custom connectors; contact AFS sales for more information. especially from the terminating devices. CNG Supply System and Gas Composition CNG Composition CNG used with the Falcon regulator should be clean and dry to ensure maximum performance and durability. The particulate, oil and moisture content of the gas should be in conjunction with SAE specification J1616. Problems caused by contamination present in the CNG will not be covered under warranty. Filtration The Falcon regulator is equipped with a 40 micron sintered stainless steel filter. This filter is designed to trap only larger particles which may cause regulator malfunction and thus is not a regular service or replacement item. Supplemental coalescing filtration is required for most applications to prevent oils and other aerosol contaminants from reaching the Falcon regulator

8 Innovative Environmental Technologies Specifications The Falcon regulator specifications vary to suit customer and certification agency requirements. Please consult the Falcon regulator specification label or the test sheet accompanying your regulator for exact technical information. CNG Outlet Requirements and Performance Low-Pressure Shut-Off: AFS strongly recommends the use of a low-pressure shut-off device downstream of the regulator. In applications where the ambient temperature drops below -25 C, a low-pressure shut-off valve is required. Failure to use such a device downstream of the regulator could result in premature wear of the 1 st stage diaphragm due to high pintle travel at extreme low temperatures. See also the coolant connection section on page 2 for coolant connection requirements in lowtemperature operation. Pulsation: The Falcon regulator features a high-gain second stage to achieve quick transient response. This requires proper matching of the regulator to the fuel injection components; otherwise an oscillation can develop in the second stage of the regulator and lead to damage attributable to close-coupled operation. Matching of the regulator to the fuel system typically consists of adjusting the enclosed volume between the regulator output and injectors such that the second stage pintle assembly doesn t close shut or oscillate about its set point over the normal range of engine operation (see Figure 7). Fuel systems particularly prone to this type of damage include batch-fire systems; systems featuring fewer, larger injectors; and systems installed on engines with low idle speeds (large displacement six cylinder or 8 cylinder engines). A common technique to match the response of the regulator to the injection components consists of adding a particle filter of adequate volume between the regulator and injectors. Placing a filter close to the injectors may also increase the dynamic range of the injectors. To demonstrate this concept further, refer to Figure 7. This represents the operation of a typical fuel-injected engine over several milliseconds. The top trace represents typical injector opening cycles. They have close to a square wave shape as the injectors open quickly, stay open for a moment, then close quickly until the next command to open (pulse width modulation or PWM). The middle and bottom traces represent the pressure trace at the regulator outlet in poor (middle) and well-engineered (bottom) applications. The poor installation has very little volume between the injectors and the regulator, forcing the regulator to quickly modulate flow on every injection. This is effected by movement of mechanical components, and seating of internal seals. The flat top section of each cycle s pressure trace indicate the regulator s pintle (metering element) has seated or nearly seated, compressing the elastomeric seals each time. This continuous activity will quickly wear out a regulator. The well-engineered installation incorporates enough pulsation volume between the regulator and injectors to ensure that the regulator pintle activity is much less. The pintle regulates gas flow by floating near its seat, without constant repeated compression of the seat. This ensures long regulator life and more stable and predictable pressure at the injectors. Note: Proper matching of a regulator to an application requires engineering expertise. The above is intended only to assist the integration engineer, not as a replacement for thorough application analysis. Because of the wide range of applications possible, warranty coverage for the Falcon regulator requires AFS buy-off of the AFS Falcon Regulator Application Evaluation

9 Falcon Natural Gas Regulator Figure 7: Falcon outlet pressure traces - 9 -

10 Innovative Environmental Technologies Terminology Creep is the increase in outlet pressure at zero flow. This is caused by gas seeping past the regulator pintle assembly (from high pressure to low pressure). As the pintle assemblies are designed for precision dynamic flow metering (not static sealing), creep will always occur to some extent. For this reason, the Falcon incorporates a high-pressure shut-off valve immediately upstream of the first stage regulator pintle. This provides positive shut-off and allows only minimal creep when the engine is turned off. Droop is the change in outlet pressure caused by increasing flow rate (see Figure 8 and Figure 9). A well-designed regulator seeks to minimize droop for accurate fuel 1050 control under any engine operating condition Cylinder Pressure Effect is the change in 950 outlet pressure resulting from decreasing Regulator Outlet Pressure (kpa) inlet pressure. Because typical fuel storage pressure ranges from 25 MPa to less than 1 MPa, keeping the outlet pressure consistent under any inlet pressure is a demanding requirement. The Falcon s two-stage design provides outstanding resistance to the cylinder pressure effect. Hysteresis is the difference in outlet pressure at a given flow rate depending on whether flow rate is increasing or decreasing (see Figure 8 and Figure 9). Excessive internal damping can result in high hysteresis, resulting in poor fuel control. A welldesigned regulator must balance quick, accurate response with stable performance. Falcon Regulator Flow 1000 kpa Flow (g/s) Figure 8: Typical regulator outlet flow (1000 kpa setpoint). 750 Falcon Regulator Flow 700 kpa Regulator Outlet Pressure (kpa) Hysteresis Droop Flow (g/s) Figure 9: Typical regulator outlet flow (700 kpa setpoint)

11 Falcon Natural Gas Regulator Figure 10: Falcon mounting dimensions and hole locations For Technical Support, contact: Bay 1, th Street N.E. Calgary, Alberta T2E 7A9 Canada Phone: +1 (403) Fax: +1 (403) Bay 1, th Street NE, T2E 7A9 Phone: +1 (403) Fax: +1 (403) Web: Printed in Canada

26 - COOLING SYSTEM CONTENTS ENGINE COOLING - DESCRIPTION... 3 ENGINE COOLING - OPERATION... 9 COOLING SYSTEM FAULTS... 1

26 - COOLING SYSTEM CONTENTS ENGINE COOLING - DESCRIPTION... 3 ENGINE COOLING - OPERATION... 9 COOLING SYSTEM FAULTS... 1 26 - COOLING SYSTEM CONTENTS Page LAND ROVER V8 DESCRIPTION AND OPERATION ENGINE COOLING - DESCRIPTION... 3 ENGINE COOLING - OPERATION... 9 FAULT DIAGNOSIS COOLING SYSTEM FAULTS... 1 REPAIR COOLANT - DRAIN