The Mark V Air/Fuel Controller - Technical Manual -

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1 Neutronics Enterprises Inc. The Mark V Air/Fuel Controller - Technical Manual - For Technical Information contact: Neutronics Enterprises Inc West Bernardo Court. San Diego, CA (858) Fax (858) This manual contains information considered proprietary to Neutronics Enterprises, Inc. It may not be copied, except in its entirety, without expressed written permission of Neutronics Enterprises, Inc by Neutronics Enterprises Inc.

3 Neutronics Enterprises Mark V Air/Fuel Controller Technical Manual Contents Description of the Mark V controller 1 Controller 2 Components included in system 2 Additional components required 2 System Components 3 Heated Oxygen sensor 3 Motorized Fuel Control Valve 3 Requirements for Proper operation 5 Locating and Mounting the controller 6 Mounting Motorized Fuel Control Valve 7 Mounting Heated O 2 Sensor 11 Initial Mark V controller setup 12 Trouble Shooting 15 User Notes 18 Figures Figure 1 Controller s Front Panel 1 Figure 2 General electrical layout of Mark V 4 Figure 3 Motorized Fuel Control Valve 7 Figure 4 Diagram of typical application 9 Figure 5 Heated O2 sensor 10 Figure 6 Power supply debugging flow chart 16 Figure 7 De-bugging test points 17

De scription of t he Mar k V con troller Figure 1 This installation guide is intended for use by a professional familiar with the operation and adjustment of the prime mover.

4 De scription of t he Mar k V con troller Figure 1 This installation guide is intended for use by a professional familiar with the operation and adjustment of the prime mover. Any adjustments made to the air/ fuel ratio, timing,or air inlet temperatures can drastically effect the safe operation of the engine. At no time should the prime mover be allowed to operate in an unstable condition because severe engine damage can result from a short period of unstable operation. Knowing how adjustments will effect the prime mover is essential to achieving a successful, safe installation. Always adhere to all local electrical and mechanical codes. 1

5 CONTROLLER he Mark v controller is a microcomputer controlled fuel management system. he unit receives inputs from a heated oxygen sensor and has outputs to drive a uel control valve. The Mark V can be adjusted using the front panel. All hanges made to the set points are stored in memory and will be recalled whenever the unit is powered on. The controller features a simple push button etup with LED indicators to show the oxygen sensor s voltage, fuel control alve s position, the valve response rate and the mixture adjust target voltage. COMPONENTS INCLUDED WITH YOUR SYSTEM MARK V computer by NEUTRONICS 18mm heated oxygen sensor with a 18mm oxygen collar to be welded into the exhaust system. Stepper motor operated fuel control valve Six foot 15 pin wiring harness with inputs for the O 2 sensor, fuel valve, and power supply Extra 4 Amp fuses (2) Operating manual and electrical diagram ADDITIONAL COMPONENTS REQUIRED An additional valve is needed to adjust the fuel supply to the motorized fuel control valve. (See Figure 3 on page 7) We recommend a 3/8 Whitey B-1RM6 needle valve. The B-1RM6 is a highly linear eight-turn needle valve. System Components 2

6 HEATED OXYGEN SENSOR A DC milli-volt signal is transmitted from the oxygen sensor to the controller. This signal will cause the MARK V to increase or decrease the amount of fuel being delivered by its motorized fuel valve. The desired set point is determined and programmed by the user into the controller. Any deviation from this setting will cause the MARK V to bias the fuel flow and bring the air/fuel ratio back to the desired setting. The MARK V controls the fuel flow to the engine to maintain a user selected air/fuel ratio defined reaction speed. MOTORIZED FUEL CONTROL VALVE Fuel enters the fuel valve through the 3/8 NPT hole in the side of the unit. A moving tapered pintle in the valve body increases or decreases the amount of fuel delivered through the 1/4 NPT exit on the bottom of the valve. (See figure 3, page 7) When the controller receives a milli-volt signal from the oxygen sensor below the set point voltage the pintle is opened allowing a greater fuel flow rate to be delivered to the engine. The reverse is true for a millivolt signal above the set point voltage. As the system stabilizes the valve changes will be minimal and the midrange positioning of this seat is desirable during normal full load operation. Adjusting the system to achieve this middle position will allow the MARK V control over a broader range of conditions. This can be accomplished by setting the throttle and the gas pressure and/or adjustment of the whitey needle valve. 3

7 Figure 2 General electrical layout of Mark V controller Requirements for Proper Operation 4

8 The MARK V is a continuously monitoring air/fuel controller designed to maintain the optimum ratio of fuel to air in the combustion chamber. This device is not intended to compensate and correct for a malfunctioning prime mover. The engine must be in sound condition, capable of achieving and maintaining stable load operation with a slightly rich air/fuel condition. To attain optimal system performance any devices that are malfunctioning must be adjusted and or replaced. Verify that the following are operating correctly to minimize any adverse changes in the emissions produced by the unit being controlled. Spark plugs are to be clean and gapped according to manufacturers recommendations Valves are to be in good condition set to the correct clearances Spark timing is to be verified and adjusted if necessary Air inlet system is to be clean and supplying a constant flow of air at a constant temperature Carburetor or fuel injection systems must deliver a steady, controllable amount of fuel to the engine Dual carburetor or dual turbocharged engines must be balanced so that both sides of the engine receive the same amount of fuel and or boost pressure Fuel pressure supplied to the motorized metering valve must be greater than the regulated fuel being delivered to the carburetor. Very low gas pressure (less ten 10 of water) can cause the motorized valve to override the engine gas regulator. To overcome these problems install a 5/8 spacer plate between the intake manifold and the carburetor. Drill and tap the plate for a 1/4 gas line connection. (See figure 4, page 9) On turbocharged engines, if the bypass fuel is being introduced after the turbo charger the fuel pressure delivered to the 5

9 motorized metering valve must be greater than the full load boost pressure. Locating and Mounting the Mark V controller MARK V CONTROLLER LOCATION & MOUNTING Mount the MARK V controller as close to the prime mover as possible. Leave the front cover accessible to permit adjustments during set-up. Do not expose the controller or any of its components to moisture, high EMF, high voltages, or extreme heat. Removing the clear front cover can access the 4 mounting holes. Insert a fastener in the holes provided (one in each corner). Sheet metal or machine screws are acceptable. If mounting the controller in a high vibration area, purchase and install 4 vibration isolators, attaching them to the back of the unit in the holes provided. Connect the wires from the control box harness to a 12 to 24 VDC power source. (Figure 2, page 4) Attach the 3-pin connector to the oxygen sensor. (Figure 4) Attach the 4-pin connector to the motorized fuel control valve. (See figure 2 page 4 and figure 3 page7) There are two fuses installed in the system. One 4-Amp fuse is mounted on the circuit board, which protects the components from short circuit. The second 4-Amp fuse is mounted in the wiring harness and protects the hardware and oxygen sensor from short circuit. Use provided automotive quality replacement fuses. MOTORIZED FUEL CONTROL VALVE Install and secure the control valve in a location where the fuel being supplied will be delivered equally to all cylinders. 6

10 Installing the control valve prior to the engine carburetor butterfly will minimize load changes as the air/ fuel mixture changes. Possible locations to install the valve are: 1) Air inlet system 2) Above carburetor 3) Intake manifold (if the intake location is used, be sure the fuel is being distributed evenly to all cylinders) 4) Fuel line to the carburetor after the gas regulator 5) See figure 4 page 9 for the perfered instalation. Figure 3 - Motorized fuel control valve INLET OUTLET 7

11 Locate a suitable spot to drill, tap and install a 3/8 NPT fitting to supply fuel to the motorized fuel control valve. The typical location is on the gas inlet line to the carburetor. Gas rated pipe or tubing should then be used to connect to the 3/8 NPT fitting. A Whitey B-1RM6 needle valve should be installed in line with this tube or pipe. The tube or pipe should then be attached to the inlet of the motorized fuel control valve. Standard gas sealing for all threaded connections must be used to prevent leaks. The motorized fuel control valve should be rigidly mounted to avoid excessive flexing or movement of the valve or the pipes and tubing. Also the valve should be mounted to avoid heat from exhaust manifolds or other hot engine parts. Use a 1/4 NPT fitting to go from the outlet side of the motorized fuel control valve to the carburetor side of the gas regulator. Drill a hole in the selected location and tap for size of fitting selected. Use standard thread sealing methods to ensure gas tight connections. Connect the 4-pin connector to the motorized fuel control valve. Make sure the wire cable and gas lines are routed to avoid hot engine parts, which could melt the insulation. 8

12 Figure 4 9

Mounting the heated Oxygen sensor The heated oxygen sensor should be located in the main exhaust stream so that it is able to sense any changes in the discharged exhaust.

13 Mounting the heated Oxygen sensor The heated oxygen sensor should be located in the main exhaust stream so that it is able to sense any changes in the discharged exhaust. The oxygen sensor must be installed so as to sample raw exhaust leaving the engine prior to any other exhaust-conditioning devices. On dual exhaust systems install the oxygen sensor in a location after both sides connect to a single common pipe. Figure 5 Drill the exhaust pipe to accept the 18 mm threaded collar and weld the supplied insert to the exhaust pipe, located as 10

14 described above. Screw an old spark plug into the collar before welding to prevent distortion. Apply anti-seize to the threads and install the oxygen sensor and torque to 18 ft. lbs. attach the wire harness and route the harness to the controller away from any high heat sources that could damage the wiring. A 6-foot harness is provided; if the harness needs to be extended use the same gauge wire (#18) and insulate each connection. Make sure each end is connected to its corresponding color. (Yellow/yellow, black/black and red/red). Extending the wires incorrectly will damage the oxygen sensor and the MARK V controller. Connect the other end of the harness to the controller using the connector plug. It is recommended that the maximum length of oxygen sensor wire be limited to 16 feet. This will minimize extraneous noise signals. Initial Mark V Controller set-up Before starting the engine close the adjustable fuel needle valve (whitey needle valve) located inline with the motorized fuel control valve. (Figure 4 page 9) Make sure power switch on Neutronics Mark V controller is off. Setup and have emission testing equipment available. Start the engine and let it warm up to normal operating temperature. Using emission testing equipment adjust mixture to about 1% O 2 in exhaust measured before the converter. Apply rated load to engine and re-check O 2 level and re-adjust as necessary to optain1% O 2. With the adjustable needle valve still closed, turn on the power switch to the Mark V computer. The motorized fuel control 11

15 valve will initialize to the closed position. You should see the green power indicator light up. The LED indicator display in the left side will show the oxygen senor voltage. If the mixture is adjusted correctly the O2 display should show an O2 voltage of less than.4 volts. If the voltage is above this level then lean out the mixer until the voltage shows.4 volts or less. Turn off the power switch to the Mark V computer to reset the internal 75-second startup timer and close the motorized fuel valve. Open the adjustable needle valve 4 turns open. Monitor the O 2 sensor voltage on the display on the left side of the Mark v controller. After the 75-second delay timer expires the motorized fuel control valve will start to open and start to supply fuel in response to the O 2 sensor signal. The valve moves initially in very fine steps and may take a minute or more to affect the mixture. The motorized fuel valve will continue to add fuel until the O 2 sensor reports that the mixture has reached the target value. You should see the O 2 sensor voltage increase to between.5 and.6 volts. Measure the exhaust emissions with your portable emission tester to check that the O 2 percentage in the exhaust before the converter is between.2% to.5%. O 2 readings in this range usually produce good emission results post catylitic converter. If the valve position is showing over 25% then it is necessary to richen the base mixture at the mixer. If the valve position is below 5% then it will be necessary to lean out the base mixture at the mixer. After the valve is in the 5% - 25% window then it will be possible to make fine adjustments to the mixture by following the next instructions. If the measurements of the exhaust indicate a lean mixture (high NOx and low CO) then it will be necessary to do the following items. Press the mode select switch once and you should see the indicator under valve position light up. The display on the left will now indicate valve position in percent. If the valve 12

16 position is showing between 5% and 25 % then press the mode select display switch 2 more times until the indicator under O 2 target is on. The display on the left will be displaying the O 2 target voltage. To make the mixture richer it is necessary to raise the O 2 target voltage. To do this press and hold the increase button. The target increases in small steps at one step per second while the increase or decrease button is pressed. As the target voltage is raised the display will show the new value. We have found that for natural gas fueled engines that a target of between.55 and.60 volts works best for emissions. After changing the target voltage you can return to the O 2 voltage display by pressing the mode select button again. Depending on the amount of change you have made to the target you should see the O 2 voltage increase on the display. If the exhaust gas measurement shows a rich mixture (high CO and low NOx) then it will be necessary to do the following things. Press the mode select switch once and you should see the indicator under valve position light up. The display on the left will now indicate valve position in percent. If the valve position is showing between 5% and 25 % then press the mode select display switch 2 more times until the indicator under O 2 target is on. The display on the left will be displaying the O 2 target voltage. To make the mixture leaner it is necessary to lower the O 2 target voltage. To do this press and hold the decrease button. The target decreases in small steps; one step per second while the button is pressed. As the target voltage is lowered the display will show the new target voltage. We have found that for natural gas fueled engines that a target of between.55 and.60 volts works best for emissions. After changing the target voltage you can return to the O 2 voltage display by pressing the mode select button again. Depending on the amount of change you have made to the target you should see the O 2 voltage reduction on the display. The valve step rate can be adjusted by selecting valve rate from the mode select menu. The valve step rate can then be adjusted in a similar fashion to the O 2 target voltage. In general 13

17 the best results will be found using a slower step rate. Faster rates might be useful in systems where there are frequent and large changes in load causing large mixture changes. During setup monitor the systems emissions using a portable emission tester. Once the desired set point has been reached the controller should achieve a smooth operation with very little fuel valve movement. The indicator display lights indicate how the system is responding. By alternating between the O 2 Volts and O 2 target displays it is simple to adjust the mixture and see the O 2 sensor s voltage change in response to the new target voltage setting. Making small changes and allowing time for system to stabilize between changes will allow you to obtain optimal system performance more quickly. Making large, quick changes could cause poor system performance and could cause an unstable engine condition. Patience is required and will yield the best results. All changes to set points will be retained by the computer if the power is turned off. TROUBLESHOOTING The green light is not on.--bad power and/or ground-- No lights are lit when power is applied to system. Check that there are fuses in both the circuit board and wiring harness. Check with an Ohmmeter that the fuses are not blown. Replace with supplied four-amp fuse if defective If the fuses are good and the green light is not on, check that the 12/24-volt power and ground are connected. Use a voltmeter to check power. It should be at least 12 VDC. Use a voltmeter set to DC volts for all checks Ground the meter to the point shown in figure 7 Check that there is volts present at TP2 if not check supply and check harness fuse 14

18 Check that there is volts present at TP1 if not replace fuse To check O 2 voltage touch voltmeter probe to TP3. Normal voltage will be changing depending on mixture. If voltage is constant high (.7 volts or above) or constant low (.3 volts or less) then check mixture settings. (See controller section) If voltage is constant.5 volts then the O 2 sensor may be bad and in need of replacement. Also check for a broken wire or loose connector. If power and fuses are functional and computer does not come on contact Neutronics for a replacement computer. See the flow chart (figure 6) for power checking sequence. If power and fuses check OK and computer still does not power up contact then Neutronics for a replacement computer. See figure 5, flow chart for power checks. 15

19 Figure 6 Power supply debugging flowchart Power check Power source=12-15 volts No Check battery connections Yes Check control mounted 4 amp fuse Good Check 4 amp fuse in wire harness Blown Replace fuse and continue power checks Bad Good Replace and continue power checks Is green "power OK" lamp on? Yes Power checks OK No Check ground connections to power source Check power 12 volts at red wire on connector No voltage block Recheck4 amp power fuses in the harness and on the board If OK replace controller 16

20 Figure 7(Debugging test points) NOTES 17

21 18 NOTES

22 NOTES 19

23 20 NOTES

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CAUTION: CAREFULLY READ INSTRUCTIONS BEFORE PROCEEDING

Daytona Sensors LLC Engine Controls and Instrumentation Systems Installation Instructions for Wide-Band Exhaust Gas Oxygen Sensor Interface CAUTION: CAREFULLY READ INSTRUCTIONS BEFORE PROCEEDING OVERVIEW