ASTM D6201 Dynamometer Evaluation of Unleaded Spark-Ignition Engine Fuel
ASTM D6201 Standard Test Method for Dynamometer Evaluation of Unleaded Spark-Ignition Engine Fuel for Intake Valve Deposit Formation
10. Preparation of Apparatus
10.1 Test Stand Preparation:
10.1.1 Instrumentation Calibration - Calibrate all sensors and indicators before or during the test as required by the particular types of instrumentation utilized. Section 11 provides details on all calibration requirements.

10.1.2 Exhaust Back Pressure and Exhaust Emissions Sample Probe Inspection - The exhaust back pressure and exhaust emission sample probes can be used until they become unserviceable. Inspect probes for wear, cracks, contamination, residue, and so forth, and replace if necessary.

10.1.3 External Hose Inspection - Inspect all external hoses for wear, cracks, contamination, unspecified restrictions, and so forth, and replace as necessary.

10.1.4 Engine Wire Harness Inspection - Inspect the engine wire harness for broken connectors, broken wires, frayed wires, general integrity, and replace or repair as required.

10.1.5 EGR Voltage Readout Preparation - The EGR voltage signal is located at Pin 27 of the Ford EEC-IV Processor. Connect a voltage readout device to Pin 27 (output) and Pin 46 (signal return) of the Ford EEC-IV Processor.

10.2 Engine Block Preparation:
10.2.1 Piston Top Preparation and Inspection - Inspect piston tops for integrity. Ensure there are no unusual wear patterns on piston tops (pitting, scratches, and so forth). Make sure piston tops are completely clean of all deposits. Use appropriate solvents (see 7.4), a walnut shell blaster, or other appropriate tools to clean the piston tops. Make sure the tools used do not alter the piston top surface, and the piston-to-cylinder wall crevices are clean of all contaminants.

10.2.2 Cylinder Bore Inspection - Inspect cylinder bores for unusual wear (scores, pits, etc.). Inspect the integrity of the engine block by monitoring the engine's compression pressure, percent leakdown, and oil consumption (see 12.3.4). The block should be replaced if unusual wear is detected.

10.2.3 Cylinder Head-to-Cylinder Block Mating Surface - Clean the cylinder head-to-cylinder block mating surface of any gasket material or deposit using a gasket scraper, the appropriate solvents (see 7.4), a walnut shell blaster, or other appropriate tools.

10.3 Preparation of Miscellaneous Engine Components:
10.3.1 Fuel Injector Preparation - Prior to engine installation, evaluate all injectors (new and used) for spray-pattern and flow-rate using a suitable apparatus as defined in 6.4. The evaluation procedure is outlined in this section. Injectors may be cleaned and reused if the criteria outlined in this section are satisfied.
10.3.1.1 Flush New Injectors - Flush new injectors for 30 s to remove any assembly residue before flow testing.

10.3.1.2 Operating Flow Rig - Using a rig as described in 6.4.13, turn on the fuel pumps, the flow meter, and the timer. After the pumps are turned on, the test fluid (see 7.5) will start to flow through the slave injector. Maintain the test fluid pressure supplied to injector at 290 +/- 1.4 kPa (42 +/- 0.2 psi) during the entire test. The maintenance of this pressure is very critical because a small change in pressure will have a dramatic effect on the flow rate and spray pattern.

10.3.1.3 Flow-test Injectors - Flow-test each injector for three 60-s periods. Record each of these measurements. The final flow rate of the injector is based on the average of these three, 60-s trials.

10.3.1.4 Observe Spray Quality - While the injector is flowing, make a visual observation of the spray pattern quality. Record this observation for each occurrence. Reject any injector that demonstrates an abnormal spray pattern. When the injector is not open, the injectors shall not leak or drip with the test fluid under pressure. Replace any injector that drips or leaks.

10.3.1.5 Acceptance Criteria - Meet the following guidelines when selecting injectors to be used for this test method. Do not use groups of injectors or individual injectors not meeting the following guidelines.
(a) Flow Specification-Individual Injectors - Flow-test individual injectors at 290 +/- 1.4 kPa (42 +/- 0.2 psi) using Stoddard solvent at 15 to 25°C (59 to 77°F) and specific gravity of 0.754 to 0.82. Adjust flow rates for test conditions of fluid temperature and pressure. Individual injectors shall have flow rates of 2.13 to 2.18 mL/s.

(b) Flow Specification-Groups - Groups of four injectors shall not have any one injector deviate from the four injector average by more than 3 %.

(c) Visual inspection Criteria - Injectors shall not drip while under pressure for at least 30 s when the injectors are not open. Any injector that demonstrates an abnormal spray pattern while the injectors are being flowed shall not be used.

10.3.2 Intake Manifold Preparation - Make sure the intake manifold is clean before each test. Use an acceptable cleaning agent such as a commercially available carburetor cleaner or Stoddard solvent. Inspect the intake manifold for integrity. The intake manifold can be used in repeated engine builds until it becomes unserviceable.

10.3.3 PCV Valve Preparation - Use the PCV valve flow rate measuring device to verify the flow rate of the PCV valves before and after the test. Measure and record the flow rates of the test PCV valves before and after the test. The appropriate PCV flow rate measuring device to use is detailed in 6.4.14. Measure the flow rate twice and average the readings. Reject any PCV valve that does not adhere to the following specifications:
24.1 to 32.6 L/min (0.85 to 1.15 ft3/min) at 60.8 kPa (18 in. Hg) vacuum
52.4 to 60.9 L/min (1.85 to 2.15 ft3/min) at 27.0 kPa (8 in. Hg) vacuum

10.4 Cylinder Head Preparation:
10.4.1 Valve Labeling - Use new intake and exhaust valves for each test. Mark each valve prior to valve weighing. For example, an intake valve that is going to be used in Test No. 5 and inserted into the number one cylinder intake valve position could be marked T5No.1In. Place all valve markings on the valve stem between the top of the valve and the valve seal-to-valve stem contact area.

10.4.2 Valve Seat and Face Cutting - Cut intake and exhaust valve faces (areas that contact the valve seats) to a 45°angle. Double cut the intake and exhaust valve seats. The first cut should be at a 45°angle. The second cut should be at a 30° angle perpendicular to the axis of the valve guide and located on the outer diameter of the seat. A 60° cut can be utilized to adjust the valve seat to valve face interface as required.

10.4.3 Valve Seat and Face Lapping - Lap each intake and exhaust valve using Fel Pro Clover 320 Grade 1A Silicone Carbide Grease Compound (Part No. 1A51804)17 for 20 s.

10.4.4 Valve Seat and Face Cleaning - Clean the valves by dipping in Stoddard solvent and wiping with a soft towel. Clean the seats with Stoddard solvent and wipe dry with a soft towel. Wash valves with n-hexane or cyclohexane. Gently shake off any remaining solvent. Place valves in an oven (see 6.4.4) at 93 +/- 5°C (200 +/- 9°F) for 5 min. Place valves in a desiccant for 1 h.

10.4.5 Valve Weighing - Weigh and record the valve weights to the nearest 0.0001 g.

10.4.6 Valve Stem-to-Guide Clearance Measurements - Measure and record intake and exhaust valve stem-to-guide clearances at the top, center, and bottom of the guide. Two sets of measurements shall be taken in the guide. The first set of measurements shall be taken 3 mm from the top of the guide, at the center of the guide, and 3 mm from the bottom of the guide. The second set of measurements shall be taken 90° from the first set of measurements. The valve stem shall be measured in the three locations that correspond to the valve guide measurements. The clearances shall be within the specifications listed below:
10.4.6.1 Valve Stem-to-Guide Clearance Specifications:
Exhaust: 0.038 to 0.140 mm (0.0015 to 0.0055 in.)
Intake: 0.025 to 0.069 mm (0.0010 to 0.0027 in.)

10.4.7 Valve Seat Width Measurements - Measure and record the valve seat widths to the nearest 0.025 mm (0.0009 in.).
10.4.7.1 Valve Seat Width Specifications:
Intake: 1.524 to 2.032 mm (.060 to .080 in)
Exhaust: 1.778 to 2.286 mm (.070 to .090 in)

10.4.8 Valve Spring Free Length Measurements - Measure and record the valve spring free length dimensions. Experience has shown that the springs should fall within the specifications shown in 10.4.9.

10.4.9 Valve Spring Loading Measurements - If the springs are within the specifications for free length dimensions, measure the load on an unassembled valve spring calibration device. The spring loading is measured at a compressed height of 29.5 mm (1.16 in.). Experience has shown that the valve spring parameters should be within the specifications shown below.
10.4.9.1 Valve Spring Specifications:
Free length: 50.3 to 53.8 mm (1.98 to 2.12 in.)
Load: 67.3 +/- 3.6 kg at 29.5 +/- 0.76 mm deflection (148 +/- 8 lb at 1.16 +/- 0.03 in.)

10.5 Cylinder Head Assembly:
10.5.1 Valve and Valve Seal Installation - Lubricate each valve seal and valve stem with the specified test oil. Insert each valve into the cylinder head. Install the valve seal over the end of the valve stem with a plastic installation cap in place. Carefully seat the seals fully on the guides.

10.5.2 Valve Spring and Retainer installation - Install prescreened valve springs and retainers. When installing the valve springs and retainers, do not compress the springs excessively. Excessive spring compression can damage the valve seals.

10.5.3 Valve Spring Assembled Height Measurements - Measure and record the assembled height of the valve springs according to the procedure described in the 1994 Ford Aerostar, Ranger, Explorer Service Manual20. The assembled height shall be between 37.85 mm and 39.37 mm (1.49 in. and 1.55 in.).

10.5.4 Valve Leak Check - It is recommended to perform a valve leak check on the cylinder head. Seal off the cylinder head's combustion chambers with a metal plate and a cylinder head gasket. Apply 480 kPa (70 psi) to each combustion chamber through the spark plug hole and record the percent leakdown. The percent leakdown should not be greater than 5 % in any of the combustion chambers. If the percent leakdown is greater than 5 % in any of the combustion chambers, then the suspect valve(s) should be re-cut or re-lapped, or both, as well as reweighed until the percent leakdown is less than 5 %.

10.6 Cylinder Head Installation:
10.6.1 Cylinder Head Torquing - Install the assembled test cylinder head on the engine. Do not use any sealing or anti-seizure compound on the cylinder head gasket. Install and torque the head bolts according to the procedure described in the 1994 Ford Aerostar, Ranger, Explorer Service Manual.

10.6.2 Spark Plug Installation - Install new Motorcraft F3TE-12405-BA spark plugs into the cylinder head. Gap the spark plugs to 1.06 to 1.17 mm (0.042 to 0.046 in.). Torque the spark plugs to 6.8 to 13.6 N-m (5 to 10 lbf-ft).

10.7 Final Engine Assembly:
10.7.1 Camshaft, Rocker Arms, and Camshaft Drive Sprocket Installation - Install the camshaft, rocker arms, and camshaft drive sprocket. Collapse all lash adjusters before the rocker arms are installed to prevent potential damage to the valves when the timing belt is installed and tensioned.

10.7.2 Camshaft Drive Installation - Install the auxiliary shaft sprocket and align the camshaft drive. Torque the sprockets according to the procedure noted in the 1994 Aerostar, Ranger, Explorer Service manual. Install a camshaft drive belt. Use a new camshaft drive for each test. Tension the camshaft drive belt according to the procedure noted in the 1994 Aerostar, Ranger, Explorer Service Manual.

10.7.3 Water Pump and Water Pump Pulley Installation - Install the water pump and water pump pulley.

10.7.4 Camshaft Drive Belt Cover and Crankshaft Pulley Installation - Install the camshaft drive belt cover. Install the crankshaft pulley. It is advisable to make a reference mark on the crankshaft pulley corresponding to top dead center of the number one and number two pistons. The reference marks are used for the required percent leakdown test.

10.7.5 Lower Intake Manifold Runner Installation - Install the lower intake manifold runner to the test head. The lower intake manifold may be installed onto the cylinder head prior to the cylinder head being installed onto the engine block.

10.7.6 Fuel Injectors and Fuel Injector Rail Installation - Install the fuel injectors and the fuel injector rail to the lower intake manifold runner. Install injectors such that the electrical connection is at the top most (12 o'clock) position. Reference scribe markings should be placed on the fuel injectors and the lower intake manifold runner and the scribe markings should be lined up for each test.

10.7.7 Rocker Cover and Upper Intake Manifold Installation - Install the rocker cover and the production upper intake manifold.

10.7.8 Intake Air System Installation - Install the specified test intake air system. The specified test intake air system consists of the air cleaner housing, air filter, and rubber flexible tube which attaches from the air cleaner housing to the throttle body of the upper intake manifold. Refer to Fig. A1.4. Route conditioned intake air per the temperature and humidity specifications dictated in Table 1 to the inlet of the air cleaner housing. Replace the specified test air filter every test.

10.7.9 Miscellaneous Parts Installation - Install the exhaust manifold, belt tensioning system, accessory drive belt, ignition coil packs, and spark plug wires.
10.7.9.1 The belt tensioning system shall consist of the water pump pulley and the crankshaft pulley as specified by the test engine parts list detailed in Annex A2. Other parts used in the belt tensioning system shall be certified Ford OEM parts. All parts used in the belt tensioning system shall be free wheeling and shall not add any additional load to the engine other than normal frictional load losses.

10.7.10 Engine Cooling System Installation - A typical engine cooling system configuration is detailed in Fig. A1.11. Equal volumes of a commercial ethylene glycol-based low-silicate antifreeze and distilled or demineralized water shall be utilized in the cooling system. Coolant capacity is specified in 6.2.8.1.

10.7.11 External Oil System Installation - Refer to 6.2.9 for the proper external oil system configuration and installation.

10.7.12 Fuel System Installation - Refer to 6.2.5 for the proper fuel system configuration and installation.

10.7.13 Resistance-Temperature Detector (RTD) or Thermocouple Installation, or both - Install all RTDs or thermocouples, or both, into their respective locations. Refer to Section 6 for the proper locations.

10.7.14 Pressure and Vacuum Line Installation - Install all pressure and vacuum lines into their respective locations. Refer to Section 6 for the proper locations.

10.7.15 Exhaust Emission and Back Pressure Probe Installation - Install the exhaust emission probe and exhaust back pressure probe into their respective locations. Refer to Section 6 for the proper locations.

10.7.16 Engine Wire Harness Installation - Connect all engine wire harness connectors to their respective locations on the engine and engine components.