ASTM D6593 test method for evaluation of automotive engine oils
ASTM D6593 standard test method for Evaluation of Automotive Engine Oils for Inhibition of Deposit Formation in a Spark-Ignition Internal Combustion Engine Fueled with Gasoline and Operated Under Low-Temperature, Light-Duty Conditions
6. Apparatus (General Description)
6.1 The test engine is a Ford 4.6L, spark ignition, four stroke, eight-cylinder V configuration engine. Features of this engine include an overhead camshaft, a cross-flow fast-burn cylinder head design, two valves per cylinder and electronic port fuel injection. It is based on the Ford Motor Co. 4.6L EFI Crown Victoria passenger car engine.

6.2 Configure the test stand to accept a Ford 4.6L two valves per cylinder engine. All special equipment necessary for conducting this test is listed herein.

6.3 Use the appropriate air conditioning apparatus to control the temperature, pressure, and humidity of the intake air.

6.4 Use an appropriate fuel supply system (Fig. 1).

6.5 The control and data acquisition system shall meet the requirements listed in Annex A2.

7. Apparatus (The Test Engine)
7.1 Sequence VG Test Engine - The test engine kit is available from the Ford Motor Co. (A9.1). A detailed listing of all parts included in the kit is given in Annex A5. Orders for test engine hardware will be solicited yearly.

7.1.1 Non-rated parts can be replaced during the test, provided the reason for replacement was not oil related.

7.2 Required New Engine Parts - Use a new kit engine (see Annex A5), engine kit, and gasket kit for each test. Gaskets may be reused during each test as long as they remain serviceable.

7.3 Reusable Engine Parts - The parts listed in the test stand set up kit, engine dress kit, engine finish kit, and bolt kit can be reused (all of these can be used in numerous engine assemblies as long as they remain serviceable). See Annex A5. Timing chain covers can be used numerous times as long as they remain serviceable.

7.4 Specially Fabricated Engine Parts - The following subsections detail the specially fabricated engine parts required in this test method:
7.4.1 Intake Air System (see Fig. 2 and Figs. A3.1 and A3.2) - Intake air system shall use the stock Crown Victoria configuration with the air horn removed from the air cleaner.

7.4.2 Camshaft Baffles (see Fig. A3.3) - These are fabricated for attachment to the under side of the rocker cover. The clearance between the edges of the baffle and the (rocker arm cover) RAC permits a limited splash flow of oil to the top of the baffle and the RAC. Therefore, the dimensional accuracy of the baffle is important to minimize the influence on test severity. The camshaft baffle is available from the supplier listed in A9.2.

7.4.3 Crankcase Oil Fill Port - The crankcase oil fill port is located towards the rear of the left rocker cover. See item 8 and 9 on Fig. A3.4.

7.4.4 Dipstick and Dipstick Tube (see Fig. A3.6) - The dipstick has been modified for accurate oil level measurements. The dipstick and dipstick tube are calibrated as a pair. If either part is replaced, then the pair shall be recalibrated. Use the dipstick and dipstick tube available from the supplier listed in A9.2.

7.4.5 Oil Pan - Use a modified oil pan with removable baffles as shown in Fig. A3.7 from the supplier listed in A9.2.

7.4.6 Exhaust Manifold - The required exhaust manifolds (see A9.4), transition plates (see A9.3) and exhaust system are shown in Figs. A3.15 and A3.16. A heated exhaust gas oxygen (HEGO) sensor is installed in the exhaust system after each exhaust manifold.

7.4.7 Flywheel - Use the flywheel listed in Annex A5.

7.4.8 Rocker Arm Cover (RAC) - The RAC is fabricated from stainless steel and incorporates a water jacket and bolt bosses for the camshaft baffle (see Figs. A3.3-A3.5). The RAC, bolts, and washers supplier is listed in A9.2.

7.4.9 Oil Filter - Use a 60 µm screen type oil filter with a bypass (see Fig. A3.8) available from the supplier listed in X2.1.20.

7.4.10 Oil Pan Insulation - The oil pan is covered with a fiberglass insulation to reduce the effects of ambient temperature variations. The insulation supplier is listed in A9.2.

7.5 Special Engine Measurement and Assembly
Equipment - Items routinely used in the laboratory and workshop are not included. Use any special tools or equipment shown in the 1994 Ford Crown Victoria Service Manual11 for assembly. A list of these tools is shown in Annex A4. Complete any assembly instructions not detailed in Section 7 according to the instructions in the 1994 Ford Crown Victoria Service Manual.

7.5.1 Piston Ring Positioner - Use the piston ring positioner to locate the piston rings 28.5 mm (1.125 in.) from the cylinder block deck surface. This allows the compression rings to be positioned in a consistent location in the cylinder bore before measurement. Fabricate the positioner according to the details shown in Fig. A3.9.

7.5.2 Piston Ring Grinder - A ring grinder is required for adjusting ring gaps. A suitable ring grinder is noted in 7.8.5.1.

7.5.3 PCV Valve Flow Rate Device:
7.5.3.1 Use this device to verify the flow rate of the PCV valve before the test and measure the degree of clogging after the test. Fabricate the device according to the details shown in Fig. A3.10. The device shall have a full scale accuracy of 5 % and a resolution of 0.05 L/s (0.1 ft3/min) (see 7.6.7).

7.5.3.2 Calibrate the flow rate device once every six months against a standard traceable to NIST.

7.5.4 Engine Service Tools - A complete list of special tools for the test engine is shown in Annex A4. The tools are available from a Ford dealership. These are designed to aid in performing several service items, in addition to the following specific service items that require special tools to perform the functions indicated (if not self-explanatory).

7.5.5 Master Bore - Use a cylinder bore of 90.70 more or less 0.03 mm as a master bore for determining top ring gap increase for the rings in cylinders 1 and 8. Using a master bore allows for consistent measurement of top ring gap increase at end-of-test. Maintain the master bore in a temperature controlled room.

7.5.6 Oil Screen Blowdown Device - Use the device available from the supplier listed in A9.3 to blow a controlled amount of compressed air across the oil screen to remove any oil that is retained on the oil screen after allowing it to drain.

7.6 Miscellaneous Engine Components-Preparation:
7.6.1 Engine Build-Up and Measurement Area-Environment - The ambient atmosphere of the engine buildup and measurement areas shall be reasonably free of contaminants. A relatively constant temperature (within more or less 3°C) is necessary to ensure acceptable repeatability in the measurement of parts dimensions. Maintain the relative humidity at a nominal maximum of 50 % to prevent moisture forming on cold engine parts that are brought into the buildup or measurement areas.

7.6.2 Intake Manifold and Throttle Body:
7.6.2.1 The required intake manifold modifications entail blocking off the EGR port (block off plate shown in Fig. A3.11) and the coolant bypass port. Block coolant bypass port in intake manifold by tapping the hole and installing a 1/2 in. NPT pipe plug. Replace the idle air bypass motor with the idle load control system. A schematic of the system and the idle air block off plate are shown in Fig. A3.12 and Fig. A3.13, respectively.

7.6.2.2 Clean the butterfly and bore of the throttle body with aliphatic naphtha (7.7.1) and air-dry before each test. Do not disassemble the throttle body as this will cause excessive wear on the components. The idle air screw can be removed for the cleaning process. Fully close the idle air screw during test operation.

7.6.2.3 There is no specific life for the throttle body. However, the clearance between the bore and the butterfly will eventually increase and render the body unserviceable. When the clearance becomes too great to allow control of speed, load, and air-fuel ratio during Stage III, discard the throttle body.

7.6.3 Rocker Arm Cover:
7.6.3.1 Before each test, inspect the coolant jacket. If a deposit or film is present, then clean the RAC coolant jacket with a commercially available de-scaling cleaner, neutralizer, and inhibitor (8.4.4.1). An example of an acceptable cleaner is detailed in 7.7.3.

7.6.3.2 Submerge the RAC in agitated organic solvent (see 7.7.2) until clean (approximately 1 h). Rinse the parts thoroughly with hot water (> 60°C). Rinse the RAC with aliphatic naphtha (7.7.1) and allow to air-dry. Inspect the appearance of the interior surface of the RAC. If the before test rating is less than ten on the CRC varnish rating scale (Manual 14), polish the interior surface lightly with No. 0 fine steel wool to achieve a dull finish. Rinse the cover with aliphatic naphtha (7.7.1) and allow to air-dry before use.

7.6.4 Camshaft Baffle - Submerge the camshaft baffles in agitated organic solvent (see 7.7.2) until clean (approximately 1 h). Rinse the parts thoroughly with hot water (> 60°C). Rinse the camshaft baffles with aliphatic naphtha (7.7.1) and allow to air-dry. Inspect the appearance of the top surface of the camshaft baffle. If the before test rating is less than ten on the CRC varnish rating scale (Manual 14), polish the camshaft baffle with No. 0 fine steel wool to achieve a dull finish. Rinse with aliphatic naphtha (7.7.1) and allow to air-dry before use.

7.6.5 Oil Pan - Submerge the oil pan in agitated organic solvent (see 7.7.2) until clean (approximately 1 h). Rinse the part thoroughly with hot water (> 60°C). Rinse the oil pan with aliphatic naphtha (7.7.1) and allow to air-dry. Inspect the appearance of the nickel plating on the internal surface of the pan. If the before test rating is less than ten on the CRC varnish rating scale (Manual 14), polish lightly with No. 0 fine steel wool to achieve a dull finish. Rinse with aliphatic naphtha (7.7.1) and allow to air-dry before use. Replace the pan when the finish becomes unserviceable (7.4.5). Ensure that baffle attachments are in good condition.

7.6.6 Oil Pan Baffle - Submerge the oil pan baffle in agitated organic solvent (see 7.7.2) until clean (approximately 1 h). Rinse the part thoroughly with hot water (> 60°C). Rinse the oil pan baffle with aliphatic naphtha (7.7.1) and allow to air-dry. Inspect the appearance of the nickel plating on baffle. If the before test rating is less than ten on the CRC varnish rating scale (Manual 14), polish the oil pan baffle with No. 0 fine steel wool to achieve a dull finish. Rinse with aliphatic naphtha (7.7.1) and allow to air-dry before use. Replate the oil pan baffle when the finish becomes unserviceable (7.4.5).

7.6.6.1 Have the oil pan and oil pan baffles replated by the supplier listed in A9.2

7.6.7 PCV Valve - Measure and record the flow rates of the PCV valve with the calibrated flow device described in 7.5.3 and Fig. A3.10. Measure the flow rate at 25 and 60 kPa vacuum. Because of the hysteresis in the PCV valve spring, make the vacuum adjustments in one direction only. Measure the flow rate twice and average the readings. Reject any PCV valve that does not exhibit an average flow rate of 90 to 140 L/min at 25 kPa and 30 to 50 L/min at 60 kPa.

7.6.8 Water Pump Drive System - Use only the pulleys provided in the Sequence VG test stand set-up kit (see Annex A5), crankshaft, water pump, grooved idler and tensioner, and a 956 mm (37 5/8 in.) long five or six groove belt to ensure that the water pump rotates at the proper speed and direction.

7.6.9 Engine Coolant Temperature Sensor - Modify engine coolant temperature sensor by attaching a relay and a 13K V resistor between the ECT sensor and the EEC as shown in Fig. A3.14.

7.6.10 Front Cover - Modify front cover to facilitate installation of tensioner, idler, and water pump drive belt. Since the belt is routed differently from the stock location some bolt bosses may need to be altered to clear the shorter belt and the tensioner. These bolt bosses are used to attach the front end accessory drive components that are not used for this test.

7.6.11 Oil Separators - Clean with aliphatic naphtha (7.7.1) and air-dry.

7.6.12 Timing Chain Cover - Submerge the timing chain cover in agitated organic solvent (see 7.7.2) until clean (approximately 1 h). Rinse the part thoroughly with hot water (> 60°C). Rinse the timing chain cover with aliphatic naphtha (7.7.1) and allow to air-dry.

7.7 Solvents and Cleaners Required - No substitutions for 7.7.1-7.7.4 are allowed. (Warning - Use adequate safety provisions with all solvents and cleaners.)

7.7.1 Aliphatic Naphtha, Stoddard solvent or equivalent is satisfactory.

7.7.2 Organic Solvent, Penmul L460.

7.7.3 Dearsol 134 Acidic Cleaner with Inhibitor, RAC cooling jacket internal cleaner.

7.7.4 Cooling System Cleaner, Dupont or equivalent, for cleaning cooling system components external to the engine.

7.8 Assembling the Test Engine-Preparations - Use the kit parts as received from the supplier. Complete any assembly instructions not detailed as follows in accordance with the instructions in the service manual. Measure pistons and bores to determine proper compression ring gaps. Procedures listed below that pertain to the pistons and rings may need to be performed if the engine is disassembled to change piston ring gaps (12.4.1).

7.8.1 Parts Selection - Instructions concerning the use of new or used parts are detailed in 7.1.1, 7.2, and 7.3.

7.8.2 Sealing Compounds - Use a silicon-based sealer as needed between the rear seal housing-cylinder block, the cylinder block-cylinder head-front cover interfaces, cylinder head-front cover-rocker cover interfaces, and cylinder blockfront cover-oil pan interfaces.

7.8.2.1 Use silicon-based sealer sparingly since it can elevate the indicated silicon content of the used oil.

NOTE 1 - Non-silicon liquid or tape thread sealers can be used on bolts and plugs.

7.8.3 Gaskets and Seals - Install new gaskets and seals during engine assembly.

7.8.4 Pistons - Pistons are select fitted during engine assembly. Ensure that pistons are numbered with the respective cylinder bores when removed from the block to assure proper reassembly of the engine.

7.8.5 Piston Rings:
7.8.5.1 Ring Gap Adjustment:
(1) Cut the top and second compression ring gaps as required to obtain the specified blowby flow rate, using the Sanford Piston Ring Grinder. Record the ring side clearance(s) and new ring gap(s) on any ring(s) adjusted. Enter the new dimension(s) on the Supplemental Operational Data sheets. Typical forms for recording these dimensions are shown in Appendix X1. Ensure that the required ring gap delta and ring side clearance are attained (Table 1). Replace rings if smaller ring gaps are required. Measure the rings for cylinders 1 and 8 in the master bore. These measurements are required to determine the ring gap increase.

(2) Using the master bore, measure the ring gaps for the top rings in cylinders 1 and 8 prior to the start of the test.

7.8.5.2 Piston Ring Cutting Procedure:
(1) With the block in a free state, position the ring in the cylinder bore with the ring positioning tool (see Fig. A3.9) and measure the ring gap.

(2) Cut the ring to the required gap using the ring cutting burr rotated at a rated speed of 3450 r/min. Remove equal amounts from both sides of the gap. Make final cuts on the down stroke only. The ring is cut with a maximum increment of 0.125 mm until the desired ring gap is achieved.

(3) After the rings are cut remove the ring from the cutting tool, debur using a Sunnen soft stone and wipe with a dry towel.

(4) Measure the gap with the ring in its respective bore positioned with the ring positioner.

(5) Repeat Steps (2) through (4) until the desired ring gap is achieved, then wash the ring with aliphatic naphtha (7.7.1) and wipe clean with a dry towel.

(6) Weigh the ring and record.

7.8.5.3 Installation:
(1) Install the oil control rings and the compression rings on the pistons with the gaps located over the piston pin. Position the gaps at approximately 180° intervals, with the top compression ring gap toward the rear. Install the rings using a ring spreader tool, keeping the rings' surfaces parallel to the ring groove in the piston.

(2) If any rings require replacement, then measure and record the new ring gap(s) and ring side clearance(s). Calculate ring side clearance by determining the difference between the ring groove width and the associated ring width.

7.8.6 Cylinder Bore Measurements - Measure the cylinder 1 and 8 cylinder bores with the bearing caps in place. Clean the bores with a dry rag. The bores shall be clean and dry when they are measured. Use a bore gage micrometer to determine the diameter of cylinder 1 and 8 at the top, middle and bottom of the second ring travel in the transverse direction.

7.9 Assembling the Test Engine-Installations - Assemble the engine according to the instructions in the service manual unless specified herein.

7.9.1 Intake Manifold - Block the coolant bypass port in the intake manifold at the thermostat housing (7.6.2.1).

7.9.2 Piston and Connecting Rod Assembly - Pistons are select fitted at the factory and shall be installed into the same bores from which they were removed.

7.9.3 Oil System Components - All oil system components in the engine are production configuration with the exception of the oil pan which contains removable baffles.

7.9.4 Cylinder Head - Prior to the installation of the cylinder heads, clock the crankshaft keyway at 270° of crankshaft angle (45° BTDC for piston No. 1). Install the cylinder head on the cylinder block. Oil the head bolt threads lightly with EF-411 oil, and torque the head bolts according to the sequence described in the service manual. Do not use any sealing or anti-seizure compounds on the cylinder head gasket.

7.9.5 Camshaft and Related Components - The camshafts used in this test are for a Ford 4.6L truck engine application and will be different than what is shown in the service manual. The camshaft sprocket is an integral part of the camshaft. Install the camshaft in the same manner as described in the service manual with the exception of the sprocket installation.

7.9.5.1 Prior to the timing chain installation, clock the crankshaft keyway at 315° of crankshaft angle (TDC of piston No. 1) as described in the service manual. Rotate the crankshaft clockwise only, when viewed from the front.

7.9.5.2 When viewed from the rear, maintain the camshaft D-slot shall at a 90° clocked position relative to the cam cover rail.

7.9.5.3 When installing the timing chains ensure that the timing marks (mentioned above) remain aligned. Install L.H. crankshaft sprocket with timing chain on the crankshaft. Drape the L.H. timing chain over camshaft sprocket. The timing chain shall hang below the tensioner dowel.

7.9.5.4 Repeat the procedure in 7.9.5.3 for the right hand timing chain. After installation, the timing chain shall hang between the chain guide and the tensioner dowel.

NOTE 2 - There should be a minimum of chain slack on the tension side between the two sprockets.

7.9.6 Rocker Arm Cover and Baffle - Fasten the camshaft baffle to the rocker cover. Cut off the tabs from the rocker cover gasket and install it in the gasket groove on cover rail. Install rocker arm cover on the cylinder head and confirm that the baffle does not contact any valve train components. Using new rubber washers on the bolts, torque the bolts to 8 to 12 N•m (the rubber washers are not reusable). The two rocker covers are different, ensure that the correct cover is installed on the correct head (Figs. A3.4 and A3.5).

7.9.7 Oil Pan, Baffles, and Insulation - Install front and rear oil pan baffles to the oil pan as shown in Fig. A3.7. Install front baffle first. Install the oil pan according to the procedure in the service manual. Install the oil pan insulation over the oil pan.

7.9.8 Water Pump, Water Pump Drive - Install the water pump and pulley, the crankshaft pulley, and the idler and tensioner according to the service manual. These are the only components needed to drive the water pump. All other production front end accessory drive components can be discarded. Pull back tensioner and install water pump drive belt as shown in Fig. 3. Ensure that there is a minimum contact angle of 20° between the drive belt and the water pump pulley.

7.10 Engine Installation on the Test Stand - Functions that are to be performed in a specific manner or at a specific time in the assembly process are noted.

7.10.1 Mounting the Engine on the Test Stand - Mount the engine on the test stand so that the flywheel friction face is 4.0 more or less 0.5° from vertical, with the front of the engine higher than the rear. The engine mounting system should be designed to minimize engine vibration at 700 to 2900 r/min. Couple the engine directly to the dynamometer through a driveshaft. The engine cannot be used to drive any external engine accessory other than the water pump.

7.10.2 Exhaust System and Gas Sampling Fittings:
7.10.2.1 The required exhaust manifold, a typical exhaust system, and fittings for exhaust gas sampling are illustrated in Figs. A3.15 and A3.16. Exhaust components should be constructed of either solid or bellows pipe/tubing. Other type flexible pipe is not acceptable.

7.10.2.2 The exhaust gas sample probes can be used until they become unserviceable. If the existing probes are not cracked, brittle, or deformed, clean the outer surface and clear all port holes. Check the probes for possible internal obstruction and reinstall the probes in the exhaust pipe. Stainless steel probes are generally serviceable for several tests; mild steel probes tend to become brittle after one test. (Warning - Exhaust gas is noxious.) (Warning - Any leaks in the connections to the sample probe will result in erroneous O2 readings and incorrect air-fuel ratio adjustment.)

7.10.3 Oil Dipstick and Tube - Install modified oil dipstick and dipstick tube, described in 7.4.4, in the engine block at the production location and attachment points.

NOTE 3 - The intake manifold, the rocker arm covers, and the exhaust manifolds can be installed after the engine is installed on the test stand.

7.10.4 Fuel Management System:
7.10.4.1 Fuel Rail Injectors:
(1) The fuel injectors can be used for multiple tests providing they meet the flow and other requirements delineated in Fig. A3.13. Fuel injectors that have caused misfires in previous tests should be cleaned before reuse. Commercial injector cleaning fluids and flow benches are available from various manufacturers. Do not use injector cleaning fluids while operating the engine.

(2) Inspect the O-rings to ensure they are in good condition and will not allow fuel leaks. Install the fuel injectors into the fuel rail and into the intake manifold.

7.10.4.2 Electronic Engine Control (EEC) System - The fuel injector operation, cylinder firing, pulse width, ignition timing, and so forth, are controlled by the specified EEC. The EEC module is available from the supplier listed in A9.2.
(1) The EEC power shall come from a battery (13.5 more or less 1.5 V) or a power supply that does not interrupt/interfere with proper EEC operation. Connect the EEC battery/power supply to the engine wire harness with an appropriate gage wire of the shortest practical length so as to maintain 12 to 15 V DC on the STAR tester and minimize EEC electrical noise problems. Ground the EEC ground wire to the engine. From the same ground point, run a minimum two gage wire back to the battery negative to prevent interruption/interference of the EEC operation. The power supply can also be used for the Lambda measuring devices.

7.10.5 Spark Plugs - Install new Motorcraft AWSF-32PP spark plugs that have been gapped to 1.37 mm (0.054 in.) Torque the spark plugs to 9-12 N•m. Install the spark plug wiring harness. Do not use anti-seize compounds on spark plug threads.

NOTE 4 - The components used in the ignition system do not require modification.

7.10.6 Crankcase Ventilation System - The crankcase ventilation system is a closed system allowing blowby to be vented from the crankcase and drawn into the intake manifold. A description of the system operation is shown in Fig. 4. Install PCV system components and hoses as shown in Fig. A3.17.

7.10.6.1 Oil Separator and PCV Valve - Use two clean oil separators and a new PCV valve listed in the parts list Annex A5. Oil separators can be reused as long as they remain serviceable.

7.10.6.2 Three-Way Valve - Install a clean three-way valve and attach the PCV valve hose. Install the remaining PCV valve hose between the three-way valve and the intake manifold (see Fig. A3.17). Do not allow the hose to flatten at the bend after installation.

7.10.7 Intake Air Components - Install the throttle body, air cleaner assembly, and new air cleaner. Modify the air cleaner assembly to accept fittings for inlet air temperature thermocouple, pressure tap and fresh air, as shown in Fig. A3.1.

7.10.8 External Hose Replacement - Inspect all external hoses used on the test stand and replace any hoses that have become unserviceable. Check for internal wall separations that could cause flow restrictions. Check all connections to ensure security.

7.10.9 Wiring Harness - There are two wiring harnesses used on the test stand, a dynamometer harness and an engine harness. Obtain the dynamometer wiring harness from the supplier listed in A9.2. The engine harness is listed in Annex A5.