ASTM D7320 Standard Test Method for Evaluation of Automotive Engine Oils in the Sequence IIIG, Spark-Ignition Engine
8. Test Oil Sample Requirements
8.1 Selection - The supplier of the test oil sample shall determine that the test oil sample is representative of the lubricant formulation to be evaluated and that it is not contaminated.

8.2 Quantity - The supplier shall provide the test oil sample of 12 L.

NOTE 5 - A Sequence IIIG Test can be conducted with a sample of test oil as little as 10 L, provided that no spillage or leakage occur during test preparation. The greater quantity is specified to accommodate minor spillage and leakage.

8.3 Storage Prior to Test - The test laboratory shall store the test oil sample in a covered building to prevent contamination by rainwater.

9. Preparation of Apparatus
9.1 Condenser Cleaning - Immediately after completing a Sequence IIIG test, remove the stainless steel condenser assembly, disassemble it, and soak it in parts cleaning agent. After the soaking, clean the inside of the tube with parts cleaning agent and a non-cuprous bristle brush. Rinse both the blowby gas and coolant sides of the condenser with clean degreasing solvent.
9.1.1 After ten tests, or more frequently if film is present, clean the coolant side of the condenser by flushing it for one half-hour with a solution of Sequence IIIG test component cleaner at 20 g per 1 L of water. (See 7.5.) Rinse it thoroughly with tap water at 60 °C.

9.1.2 After cleaning the coolant side of the condenser, pressure check it for leaks using air at 70 kPa.

9.2 Intake Manifold Cleaning - Clean the intake manifold with degreasing solvent.

9.3 Cleaning of Engine Parts - Clean all engine parts (other than the connecting rods, block and heads; see 9.4, 9.5 and 9.6) thoroughly prior to engine assembly. Degrease the parts (any reusable parts that come into contact with test oil as shown in Table A5.2), and then soak them in parts cleaning agent (7.5.1) for a period of at least 30 min but shall not exceed 24 h. Immediately remove the cleaner by spraying with hot tap water. Blow-dry the parts with clean, dry shop air (Warning - For technical use only) and immediately coat them with a 50/50 mixture of build-up oil and degreasing solvent.

9.4 Connecting Rod Cleaning - Clean the connecting rods according to the following:
9.4.1 Clean the connecting rods by soaking in degreasing solvent for a mininum of 2 h. Spray the rods with a 50/50 mix of build-up oil and degreasing solvent.

9.5 Engine Block Cleaning - Clean the block according to the following:
9.5.1 Remove the debris in the head bolt and main bearing-cap bolt holes using class 2B bottoming taps of the appropriate sizes.

9.5.2 Physically remove all sand and slag deposits, and any other debris, from the water jacket using a sharp-ended drill rod or a long straight slot screwdriver.
9.5.2.1 Check the camshaft tunnel for sharp edges on the front of each bore and along the cross-drilled oil gallery inside each bearing bore. Deburr as necessary. See the Sequence IIIG Engine Assembly Manual, Section 1 Sheet 2.

9.5.3 Thoroughly clean the block prior to honing as follows:
For new and used blocks, remove the crankshaft, main bearings, and bearing caps. In addition, remove all bushings, bearings, and oil gallery plugs prior to cleaning.
9.5.3.1 With either a new or a used block, prevent cleaner or oil from entering the engine coolant passages. (See Sequence IIIG Engine Assembly Manual, Section 1 Sheet 4.)

9.5.3.2 Clean the block in a heated bath, a temperature-controlled automated parts washer, or ultrasonic cleaner before and after honing. Follow these suggested guidelines to ensure there is no rusting of the engine block after this process:
If Using a Heated Bath or an Automated Parts Washer:
(1) Use only NAT-50 or PDN-50 soap at a concentration of 7.3 kg of soap per 380 L of water. Change the soap and water solution at least after every 25 h of use.
(2) Control the water temperature at 60 °C +/- 10 °C.
(3) Use only fresh tap water in the bath.
(4) Prior to installing the engine in the parts washer, ensure that all coolant passages are blocked off to prevent cleaning solutions from entering the passages.
(5) Run the block through the cleaning cycle for a period of 30 min to 40 min.
(6) After the cycle is complete, immediately remove the block from the washer and spray it down with degreasing solvent.
(7) Wipe cylinder bores out with a lint free towel.
(8) Spray engine block with a 50:50 mixture of build-up oil and degreasing solvent.
(9) Do not remove the paint dot from the crankcase area of the block.
(10) Allow the block to cool to room temperature before honing the block.

If Using the Ultrasonic Cleaner Parts Washer:
(1) Based on bath volume, use solution 7 at a ratio of 132.5 mL (4.48 oz) per 3.785 L (1 gal) of water plus solution B at a ratio of 11 mL (0.38 oz) per 3.785 L (1 gal) of water. As an alternative, a 50/50 Brulin US Solution of 815 GD and 815 QR-DF may be utilized in a 12.5 % concentration.
(2) Use only fresh tap water in the bath.
(3) Control the solution-in-water temperature at 65 °C +/- 5 °C.
(4) Prior to installing the engine in the parts washer, ensure that all coolant passages are blocked off to prevent cleaning solutions from entering the passages.
(5) Run the block through the cleaning cycle for a period of 60 min.
(6) After the cycle has completed, immediately remove the block from the washer and thoroughly spray clean the block with hot water.
(7) Replace the mixture of the two solutions-in-water with a new mixture at least after every 25 h of use.
(8) Spray engine block with a 50:50 mixture of build-up oil and degreasing solvent.
(9) Do not remove the paint dot from the crankcase area of the block.
(10) Allow the block to cool to room temperature before honing the block.

9.5.3.3 See the Sequence IIIG Engine Assembly Manual, Section 2 for the honing procedure.

9.5.3.4 After honing the cylinder walls, clean the engine block again according to 9.5.3 and spray the engine block (including all oil galleries) first with degreasing solvent followed by a 50:50 mixture of degreasing solvent and build-up oil. Using this 50:50 mixture, wipe out the cylinder bores with clean cloth towels until all honing residue has been removed.

9.5.3.5 Air dry the engine block, using clean dry shop air, and coat the cylinder walls with build-up oil using soft, lint-free, clean cloths.

9.6 Cylinder Head Cleaning - Clean the cylinder heads according to the following:
9.6.1 Explore all accessible water passages with a flexible probe to detect any material that would interfere with coolant flow.

9.6.2 Clean the cylinder heads according to the recommended engine block cleaning procedure (see 9.5.3.2) or clean with degreasing solvent. Spray the heads with a 50/50 mix of degreasing solvent and build-up oil. When cleaning the heads, do not remove the paint dot.

9.7 Engine Build-up Procedure - Laboratories shall maintain engine-build data sheets as shown in Annex A17. This data shall be available to the TMC and the Test Procedure Developer for investigative studies as deemed necessary for hardware investigations during times of industry severity shifts or other problems.
9.7.1 General Information - Use only the listed service parts, special test parts, and special build up procedures specific to this test as outlined in this test method and the Sequence IIIG Engine Assembly Manual. See 6.4. Make and record measurements specified in this test method of the cylinders, pistons, rings, valve train, cam, and lifters. These measurements will provide evidence of conformance to the specifications of the method, and will provide baselines for determining engine wear that occurs during a Sequence IIIG test.

9.7.2 Special Parts - Use the special parts listed in the Sequence IIIG Engine Assembly Manual Section 8.
9.7.2.1 Hardened Seat Heads - Cylinder heads with hardened seats, part number 24502260S, can be used for non-reference oil tests once an acceptable reference oil test has been completed in the laboratory. These heads can also be reused, provided an acceptable reference oil test has been obtained with the reused heads and the criteria in section 5a of the assembly manual has been met. Once a laboratory has obtained acceptable reference oil results on both new and reused 24502260S heads, the laboratory can use either new or reused heads for any tests. When a test is conducted on an acceptable reused cylinder head with part number 24502260S, thereafter, append an "X" to the part number reported in the test report, where "X" is the number of tests the head has been used.

9.7.3 Hardware Information - Complete Form 12, Hardware Information, in standardized report form set (see Annex A8).

9.7.4 Fastener Torque Specifications and Torquing Procedures - Use the following specifications and torquing procedures when installing bolts in the engine:
9.7.4.1 Main Bearing Cap Bolts - Use new main cap bolts on every test, including tests on new engine blocks; do not modify the threads of the bolts. Do not use air tools on bolts to seat the main bearing caps in the engine block. Use a speed handle and socket, in a crisscross pattern to draw down and lightly seat the main cap. Apply build-up oil to the threads and to the surfaces of the bolts that contact the main bearing caps. In order to prevent hydraulic lock, do not apply oil to the tapped holes in the cylinder block. Install the bolts finger-tight and tighten them further with the SPS Torque Sensor I, Ingersoll-Rand ETW-E180, or Snap-on ATECH3FR250 Torque Wrench only, working from the center out in a crisscross pattern. See the Sequence IIIG Engine Assembly Manual for torquing instructions. (See Section 1 Sheet 6 for honing and Section 3 Sheet 6 for final assembly.)

9.7.4.2 Cylinder Head Bolts - Install the cylinder head bolts, GM Part No.25527831 (long) and 25533811 (short), that are of special design for yield applications using the SPS Torque Sensor I, Ingersoll-Rand ETW-E180 Torque Wrench, or Snap-on ATECH3FR250 Torque Wrench. See the Sequence IIIG Engine Assembly Manual for installation instructions. Replace the bolts after each test. (See Section 1 Sheet 7 for honing and Section 5 Sheet 3 for final assembly.)

9.7.4.3 Torques for Miscellaneous Bolts, Studs, and Nuts - Use the torques for miscellaneous bolts, studs, and nuts given in the Sequence IIIG Engine Assembly Manual.

9.8 Parts Replacement - See 9.8.1 for information regarding parts. Replace test parts as follows:
9.8.1 Install the new parts listed in Annex A5, Table A5.1 for each test.

9.8.2 Install the new parts listed in Annex A5, Table A5.2, only if the used part is no longer suitable for test purposes.

9.9 Engine Block Preparation - Prepare the engine block as follows:
9.9.1 Install new engine block freeze plugs; use a driver to facilitate this replacement.

9.9.2 Install the main bearing caps, without the bearings in place. Tighten the retaining bolts using the procedure in 9.7.4.1.

9.9.3 To prevent entry of honing fluid into the coolant passages of the engine block, cover and seal the coolant inlet passages and freeze plug openings. Close the petcocks if previously installed; if not, install 1/4 -in. NPT pipe plugs.

9.9.4 With a 30 cm smoothing file, deburr the surfaces of the block that mate with the cylinder heads to ensure adequate gasket seating.

9.9.5 Use the honing torque plates B-H-J GM 3.8L/3E-R-s _t-HT to pre-stress the engine block for honing. Install the torque plates with the proper hardened washers (supplied with the honing torque plates), single washers on top row and double washers on bottom row, to establish proper bolt depth.
9.9.5.1 Clean the threaded bores for the cylinder head attachment bolts using a bottoming tap before each installation of the torque plates.

9.9.5.2 The torque plates require the use of new head gaskets, SPO Part No.24503802 left head and 24503801 right head, along with cylinder head, torque-to-yield fasteners, SPO Part No.25527831 (long).

9.9.5.3 Clean all sealing and thread locking compounds from the fasteners for the torque plate installation. Lightly lubricate the fasteners (head bolts) during this operation with EF-411.

9.9.6 Use only the CV-616 honing machine to hone the cylinder walls. See the Sequence IIIG Engine Assembly Manual, Section 2 for all of the proper setup and operational procedures for each specific run on the Sequence IIIG engine block. Have the power output and the current verified by the manufacturer annually.

9.9.7 Replace the honing fluid, filters, and fiber mats used in the honing machine after every 15 h of honing machine operation. Use the honing machine hour meter to determine hours of operation. See the Sequence IIIG Engine Assembly Manual, Section 2 Sheet 8.

9.9.8 The flow rate of the honing lubricant should be approximately 7 L/min. In addition, do not introduce solvents into the honing fluid or use them to clean the honing stones or guides. Use only honing fluid to clean honing stones or guides.

9.9.9 Hone the cylinder walls without the main bearings in place, but with all bearing caps installed.

9.9.10 Clean the engine block following honing according to 9.5.3.2.
9.9.10.1 Allow the cylinder block to cool for a minimum of 10 min before taking final bore measurements. See Section 2, Sheet 9 of the Sequence IIIG Engine Assembly Manual.

9.9.11 If desired (this is not required), check the main bearing bore clearances using a mandrel, part BX-398-1, according to the following procedure:
9.9.11.1 Starting from the front of the block, slide the mandrel through all four main bearing bores. If excessive resistance is encountered while inserting the mandrel, remove the mandrel from the engine block and inspect the main bearing bores for burrs, nicks, dirt, alignment problems, or any abnormalities. Carefully remove any nicks, burrs, scratches, or dirt with 400-grit paper or a fine stone. Then use a clean shop towel with degreasing solvent to wipe the affected surfaces. Reinstall the mandrel to ensure that it can freely pass through all four main bearing bores. If the mandrel still will not clear the bores after completing the above steps, do not use this block and notify the Test Procedure Developer of the problem. After honing, repeat the above procedure prior to final engine build. The mandrel is an alignment and clearance gage only, not an assembly tool. The mandrel should not be in the bores when installing the main bearing caps or torquing the main bearing bolts.

9.10 Piston Fitting and Numbering - Fit the pistons to the cylinders according to recommendations listed in the Sequence IIIG Engine Assembly Manual for the run sequence of the block. Use only the specified code pistons for each run sequence. Number the pistons with odd numbers in the left bank from front to rear and with even numbers in the right bank from front to rear.
9.10.1 Piston Rings - The rings are pre-sized for each run; check the gap in the cylinder bore for each test. The top ring gap shall be 0.635 mm +/- 0.051 mm. The bottom ring gap shall be 1.067 mm +/- 0.051 mm. The top ring gap shall be smaller than the bottom ring gap and the difference between the two ring gaps shall be between 0.330 mm and 0.533 mm. If the ring gap difference is below 0.330 mm, contact the Test Procedure Developer.
9.10.1.1 Check the ring gap with a Starrett Ring Taper Gage No.270 with the ring positioned in the cylinder bore using a piston ring depth gage (drawing RX-118602-B). Remove the torque plates and position the rings 23.67 mm below the cylinder-block deck surface during gap measurement.

9.10.1.2 Record the top and bottom ring gaps on Form 12, Hardware Information, in the standardized report form set (see Annex A8). Record and report ring gaps in millimeters.

9.11 Pre-Test Camshaft and Lifter Measurements - Measure the camshaft lobe height and lifter lengths, prior to engine assembly, according to the following procedure:
9.11.1 Remove camshaft and lifters from laboratory inventory.

9.11.2 Remove camshaft and lifters from original container and packaging and set container and packaging aside for later use. Clean camshaft with degreasing solvent. Do not clean the lifters; wipe the lifters with a clean cloth or towel.

9.11.3 Make the camshaft measurement using Mitutoyo Snap Gauge, model 201-152, and a Mitutoyo Digital Indicator, model 543-252B, to measure the camshaft lobes. Make the lifter measurement with a digital indicator equipped with a Mitutoyo 4.3 mm flat tip, model 131-259 mounted in a indicator stand. Equip the indicator stand with a V-block that is rigidly mounted to the base and locates the lifter with its center axis in line with the digital indicator. Store the camshaft and lifters in a temperature-controlled room, before making dimensional measurements, for at least 90 min to ensure temperature stabilization.
9.11.3.1 Use Mitutoyo Digital Indicator for measurement accurate to 0.001 mm. Before each measurement session, use standards traceable to the National Institute of Standards and Technology, to ensure measuring equipment accuracy. Include standards having length values within 1.3 mm of the typical lifter and lobe measurement taken.

9.11.3.2 Use the same equipment and standards post-test measuring as were used for pre-test measuring. If a calibration shift between the pre-test and post-test measurements is detected, evaluate the shift to determine the effect on the wear measurement. Record the results of the evaluation and any corrective action taken.

9.11.4 With the camshaft positioned in a set of V-blocks, remove any burrs around the outer edge of the camshaft thrust surface, if necessary. Thoroughly clean the camshaft with degreasing solvent to remove all rust preventative coatings and blow-dry it with clean, dry shop air.

9.11.5 Measure the maximum pre-test dimension of each camshaft lobe, transverse to the camshaft axis to the nearest 0.001 mm. This dimension is at the rear edge of all lobe positions (lobes are numbered from the front to the rear of the camshaft). Record the measurements and temperature at the time of measurement on internal laboratory forms. See 9.7. After measuring, coat the camshaft with build-up oil. Return the camshaft to its original packaging and container until installed in the engine.

9.11.6 Measure the pre-test length of the lifters at the center of the lifter foot to the nearest 0.001 mm. Record the measurements and temperature at time of measurement on internal laboratory forms. See 9.7.

9.11.7 Record the unique serial number for each lifter on internal laboratory forms. See 9.7. Do not use electro-mechanical scribing devices. Do not place any marks on the lifter body or foot. Return the lifters to their original packaging until installed in the engine.

9.12 Camshaft Bearing Installation - Install the main bearing caps (see 9.14.2) before installing the camshaft bearings. The camshaft tunnel is specially processed and uses oversize bearings provided through the CPD. Install the camshaft bearings according to the Sequence IIIG Engine Assembly Manual Section, 3 Sheet 4.
9.12.1 Always inspect the lifter and main bearing oil galleries for splintered babbitt materials that might have been shaved from the outside diameter of the bearings during installation. Remove any materials from the oil galleries with clean dry shop air.

9.13 Camshaft Installation - Install the camshaft according to the Sequence IIIG Engine Assembly Manual, Section 3 Sheet 11:
9.13.1 Coat the camshaft lobes and journals with a light film of test oil.

9.13.2 Install the camshaft in the engine block, taking care to avoid damage to the lobes, journals, and bearings.

9.13.3 Installation of Camshaft Thrust Plate - Lubricate the thrust plate with build-up oil and install the thrust plate to the front of the engine block using new Torx fasteners.

9.14 Main Bearings - Verify that the main bearing bore areas in the engine block and bearing caps are clean. Install new main bearings, part number OHT3F-042-2, in the engine block and main bearing caps, and lightly oil the bearing surfaces with build-up oil. New main bearing cap bolts shall be used for each Sequence IIIG test engine build including a new engine block (discard the bolts the block was machined with).
9.14.1 Crankshaft - Install the crankshaft.

9.14.2 Main Bearing Cap Installation - Install the main bearing caps using new bolts for each test. Do not use the bolts from the new engine block for the first build; use new fasteners for the first build. Do not remove the phosphate coating from the bolts. Do not use air tools on the main bearing cap bolts to seat the caps. Install the bolts finger-tight, and tighten them according to the procedure in 9.7.4.1. Use the main bearings as received.

9.15 Crankshaft Sprocket - Install a matched set two-piece crankshaft sprocket, part number OHT3F-036-1.

9.16 Camshaft Sprocket, and Timing Chain - Install a new camshaft sprocket and timing chain.

9.17 Crankshaft Endplay - Measure the crankshaft endplay. It should be between 0.076 mm and 0.279 mm.

9.18 Piston Pin Installation - Install new piston pins and retainers for each test. Clean piston pins using a clean lint-free cloth and oil with build-up oil. The piston pins are full floating and held in place by two retainers.
9.18.1 Piston Installation - Clean pistons using degreasing solvent and air dry. Wipe the piston with a lint-free towel prior to installation.

9.18.2 Use a piston ring expander to install the pre-gapped piston rings (see 9.10.1) on the pistons.

9.18.3 Position the ring end gaps as shown in the Sequence IIIG Engine Assembly Manual, Section 3 Sheet 8.

9.18.4 Coat the cylinder walls with build-up oil and wipe them with a clean, lint-free soft cloth, repeating the process until clean; apply a final coat of build-up oil before installing the piston assembly.

9.18.5 Coat the pistons and rings with build-up oil.

9.18.6 Install the pistons in the cylinders, using a ring compressor tool.

9.19 Harmonic Balancer - Deburr the harmonic balancer key way slot and the slot on the crankshaft with a mill file. On a new balancer, remove the rolled edge on the inside diameter of the balancer so the there is a slip-fit on to the crankshaft. Do not install the balancer until after performing the oil pump priming operation in the test stand just prior to test start.

9.20 Connecting Rod Bearings - Clean the bearings using a clean lint-free cloth and oil with build up oil prior to installation. Use new connecting rod bearings, part number OHT3F-042-2, for each test, furnished as part of the engine bearing kit.
9.20.1 Install the bearings in the connecting rods, and install the bearing caps with the rods in place on the crankshaft.
9.20.1.1 Tighten the connecting rod bolts according to the specifications listed in the Sequence IIIG Engine Assembly Manual. Determine the torque specifications for the connecting rod bolts by the type of connecting rod: cast or powdered metal.

9.21 Engine Front Cover - Use a new front cover with each new engine block or if the oil pump gerotor housing is worn. Front covers can be used for as many as six tests. Remove any slag that may be present, and debur the front cover prior to use.
9.21.1 Install new oil pump gears, or a new front cover and new gears, as deemed necessary according to the Sequence IIIG EngineAssembly Manual inspection requirements Section 4 Sheet 2. Deburr machined surfaces and remove any casting slag in oil passages as necessary.

9.21.2 Install a new oil pump relief valve and spring.

9.21.3 Ensure the oil pump relief valve moves freely inside its bore in the front cover. Check the oil-pump-relief-valve clearance according to the Sequence IIIG Engine Assembly Manual, Section 4 Sheet 4.

9.21.4 Bolt the front cover and oil pump assembly to the engine block.

9.21.5 Inspect the oil pickup tube and screen assembly for cleanliness; install using a new gasket.

9.22 Coolant Inlet Adapter - Replace the water pump with a coolant inlet adapter, as shown in drawing OHT3F-031-1.

9.23 Oil Dipstick Hole - Plug the oil dipstick hole with a hole-plug (Part OHT3F-065-2). To determine the oil level at the appropriate time during a test, temporarily remove this plug and insert the calibrated dipstick (Part OHT3F-064-2).

9.24 Oil Pan - Install the oil pan, part number OHT3F-073-1, on the engine block, using a new gasket. Do not use magnetic drain plugs in the pan.

NOTE 6 - Ensure the cut out area of the windage tray/oil pan gasket does not interfere with the oil dipstick and modify if necessary.

9.25 Cylinder Head Assembly - Prepare the cylinder heads according to the following procedure:
9.25.1 Install new cup-type freeze plugs.

9.25.2 Deburr all surfaces of the cylinder heads that mate with the engine block and the manifolds with a 30 cm smooth file to ensure satisfactory gasket seating.

9.25.3 Thoroughly clean the cylinder heads according to 9.6 and air blow them dry prior to final assembly. If the automatic parts washer is not used, clean cylinder heads with degreasing solvent and spray with 50/50 solution of build-up oil and degreasing solvent.

9.25.4 Coat the valve stems and valve guides with build-up oil.

9.25.5 Install new valves for each test. Lapping or grinding of valves or valve seats, or both, is not allowed.

9.25.6 Install new valve stem seals over the valve stems onto the valve guides. Exercise extreme care when installing the seals in order to avoid either cutting the seals or mis-positioning them on the guides, thereby helping to preclude high oil consumption. See Sequence IIIG Engine Assembly Manual, Section 5 Sheet 1.

9.25.7 Install new valve springs, part number OHT3G-059-1 (color code pink). Place the smaller diameter end of the spring against the retainer. Do not remove the factory paint dot from the valve spring.

9.25.8 Install valve retainers and keepers.

9.26 Adjustment of Valve Spring Loads - Adjust the load of each valve spring according to the following procedure:
9.26.1 Before and after using the valve spring load measurement apparatus (such as Part BX-310-2), calibrate the load cell using the following technique. Use dead weights to produce the specified load of 912 N.
9.26.1.1 Load Cell to Load Cell Technique - Affix load cell weight adapter plate (see Fig.1) to calibration load cell. Zero the calibration load cell. Individually place calibrated dead weights onto calibration load cell. Verify that each dead weight indicates the appropriate force on calibration transducer readout. Repeat the calibration of the calibration load cell. The two consecutive readings shall agree within 2.2 N; if not, inspect the load cell and replace as necessary. Align calibration load cell beneath apparatus load cell. Place the air cylinder ram on the calibration load cell. Set the apparatus load cell to read the value of the calibration load cell. Apply air pressure to the aligned load cells. Vary air pressure to give several different forces, including 801 N. Determine that both calibration and apparatus transducer readouts indicate the same value, if not, adjust the apparatus load cell. Repeat the calibration of the valve-spring load-measurement apparatus. The two readings shall agree within +/- 2.2 N; if not, inspect the apparatus load cell and replace if necessary. Retain data obtained during each calibration.

9.26.2 Install a cylinder head in the holding fixture. The holding fixture shall position the cylinder head such that the valve is directly in line with the air cylinder-loading unit and no side loading of the valve takes place.

9.26.3 Install Zeroing Fixture, Part D4031, to cylinder head. Zeroing fixture, Part D4031, is part of the valve-spring load-measurement apparatus, Part BX-310-2.

9.26.4 Place the air cylinder-loading unit over a valve and check for proper alignment of the valve tip with the loading unit.

9.26.5 Position the dial indicator and its foot on the zeroing fixture to facilitate accurate measurement of valve stem axial movement.

9.26.6 Rapidly apply and release the air pressure three times to ensure free travel of the piston rod; adjust the air pressure to obtain a valve deflection reading of 9.5 mm, if necessary.

9.26.7 If the readings are not within the specifications of 912 N +/- 44 N force as shown by the load cell indicator, add or remove shims, or interchange parts as necessary.

9.26.8 Repeat steps 9.26.2 through 9.26.7.

9.27 Cylinder Head Installation - Use new head gaskets for each application. Do not use any sealers on the cylinder head gaskets. Use new fasteners, available from GM Racing warehouse part 25527831 (long) and 25533811 (short), for each application. Before using the fasteners for cylinder head attachment, remove all pre-coat sealers. Remove thread locking compounds from the threads and underside of the bolt head with a wire wheel or brush. Do not use chemical cleaners to remove these coatings. Coat the threads and underside of the bolt head using non-hardening pliable sealing compound. Tighten the fasteners according to the guidelines in the Sequence IIIG Engine Assembly Manual, Section 5 Sheet 3.

9.28 Hydraulic Valve Lifters - Do not open the hydraulic lifter to expose any part of the internal parts. Do not remove the factory-installed leak down oil. Do not use electro-mechanical or chemical means to etch identification numbers on the hydraulic lifters.
9.28.1 Prior to installation, clean the lifter body and foot using a clean cloth dampened with degreasing solvent. Do not submerse or spray the hydraulic lifter. Gently wipe the lifter body with the solvent-dampened cloth and dry using a clean dry cloth or terry towel.

9.28.2 Install the test lifters in the test engine, coating each lifter foot with test oil before installation into the lifter bore. Rotate the engine crankshaft slowly for 720° while ensuring that the lifters follow the cam lobe profile. Remove each lifter and once again coat the lifter foot with test oil. Reinstall the lifter into the engine block with the ground flat on the lifter body facing inboard toward the center of the engine. See the Sequence IIIG Engine Assembly Manual, Section 6 Sheet 1.
9.28.2.1 Use a test oil sample of 118 mL to lubricate the cam and lifters during engine assembly. Pour any remaining oil into the lifter valley of the engine after this process is complete.

9.29 Pushrods - Clean the pushrods with degreasing solvent and air blow them dry prior to installation; make certain that the oil passages are open. Wipe the pushrods with a lint-free cloth prior to installation. Lubricate the ball ends of the pushrods with buildup oil and install the pushrods. See the Sequence IIIG Engine Assembly Manual, Section 6 Sheet 2.

9.30 Valve Train Loading - Install the rocker arm pivot retainer and the precision roller rockers and torque the rocker arm pedestal bolts according to the Sequence IIIG Engine Assembly Manual, Section 6 Sheet 4. Rocker arm pivot retainers can be used for up to six tests before being replaced.
9.30.1 Once the valve train is loaded, do not rotate the engine until using the dynamometer air starter system at the start of test.

9.31 Intake Manifold - Modify the intake manifold as shown in the Sequence IIIG Engine Assembly Manual, Section 6 Sheet 7.
9.31.1 Plug the EGR port using part number OHT3F-024-1.

9.31.2 Install the positive crankcase ventilation valve, replacement plug (part number OHT3F-002-1) in the intake manifold plenum.

9.32 Rocker Covers - Install two left-side rocker covers part number 25534751 on the cylinder heads.

9.33 Water Inlet Adapter - Install a water inlet adapter made according to drawing OHT3F-034-1.

9.34 Condenser - Install a condenser mounting bracket, part number OHT3F-041-1, and condenser, part number BX-212-1 or OHT3F-075-1, with an adapter, part number OHT3F-040-1, on the front of the engine using flexible hose to connect the adapter to the rocker cover bushings, part number OHT3F-028-1.

9.35 Coolant Outlet Adapter - Replace the thermostat housing with a coolant outlet adapter, part number OHT3F-034-1.

9.36 External Oil Cooling System - Install the external cooling system as follows:
9.36.1 Install a modified Oil Filter Engine Adapter, part number OHT3F-080-1, refer to Section 4 Sheet 4 and Section 8 Sheet 3a of the Sequence IIIG Assembly Manual. Install the adapter on the engine front cover.

9.36.2 Install an Oil Cooler, part number OHT3F-030-2, using Connector part number OHT3F-039-3, as shown in the Sequence IIIG Engine Assembly Manual, Section 8 Sheet 3.

9.36.3 Install an Oil Filter Adapter Fitting, part number OHT3F-043-2, and an Oil FilterAdapter, part number OHT3F-035-2, as shown in the Sequence IIIG Engine Assembly Manual Section 8 Sheet 3.

9.36.4 Install the Bypass Valve Assembly Housing, part number OHT3F-084-1, on the Oil Filter Engine Adapter, as shown in the Sequence IIIG Engine Assembly Manual Section 8 Sheet 3.

9.37 Oil Sample Valve - Install suitable plumbing to the oil pressure fitting located in the oil filter adapter to permit the removal of oil samples. Select the plumbing to minimize the added volume.

9.38 Ignition System - Install ignition system components according to the following instructions:
9.38.1 Use high-energy ignition wires which are resistant to moisture and high temperatures.

9.38.2 Use an original equipment manufacturer coil pack mounted on the front engine mount according to drawing OHT3F-026-1.

9.38.3 Use new spark plugs; NGK part number TR-6, stock number 4177. Adjust the gaps with a wire gage to 1.14 mm. Install a set of plugs prior to test start-up. Tighten spark plugs hand-tight plus 1/16 turn.

9.39 Throttle Body - Modify a production throttle body according to the drawing in the Sequence IIIG Engine Assembly Manual, Section 7 Sheet 6.
9.39.1 Install the throttle body onto the plenum and attach the throttle body adapter, part number OHT3F-001-2.

9.40 Accessory Drive Units - Do not use any accessory drive units, such as alternators, generators, fuel pumps, power steering units, air pumps, and so forth.

9.41 Exhaust Manifolds, Water-Cooled - Prepare two water-cooled exhaust manifolds, part number OHT3F-003-1, and install one on each of the two cylinder heads using transition adapters, part number OHT3F-004-1, according to the following instructions:
9.41.1 Deburr all the surfaces of the exhaust manifolds that mate with the cylinder heads with a 30 cm smooth-cut file to ensure proper gasket seating.

9.41.2 Attach the exhaust manifolds to the heads using stainless steel studs (3/8-16 by 3/8-24 by 1 1/2 in.), stainless steel 3/8-24 nuts, and shielded exhaust gaskets, part number OHT3F-018-1 or GM 24506009.

9.41.3 Ensure that there are no leaks between the manifold assembly components that might allow outside air to enter the exhaust system through scavenging upstream of the O2 sensor.

9.42 Engine Flywheel - Install the flywheel and drive shaft plate assembly OHT3F-020-2.

9.43 Pressure Checking of Engine Coolant System - If desired, pressure-check the engine coolant system after assembly and before installation of the engine on the test stand, according to the following procedure:
9.43.1 Block all coolant outlets, and install the necessary fittings on the coolant inlet to permit pressurizing the coolant system with air, and sealing it.

9.43.2 Pressurize the coolant system with air to 100 kPa, and seal it. Monitor the pressure for 10 min. Take no corrective action if the reduction in pressure is less than 3.4 kPa in 10 min. If larger changes in pressure occur, re-torque all appropriate bolts, and replace gaskets, seals, and components (including the cylinder heads and the intake manifold) as necessary. Repeat the pressure checking.

9.44 Lifting of Assembled Engines - Lift the assembled engines with a suitable lift chain.

9.45 Mounting the Engine on the Test Stand - Mount the engine on the test stand according to the following:
9.45.1 Use OHT3F-026 front and OHT3F-025 rear engine mounts.

9.45.2 Mount the engine in such a manner that the intake plenum mounting flange-to-intake manifold interface is horizontal.

9.45.3 Install an engine flywheel guard, safety housing, and air starter mounting assembly (part of OHT3F-025).

9.45.4 Connect the engine to the dynamometer with a flywheel-to-driveshaft coupling adapter (part of OHT3F-020-1) and a driveshaft.

9.45.5 Install a coolant drain valve in the middle of each side of the block, in the 1/4-in. NPT hole. The use of street ells and petcocks are satisfactory. Petcocks shall remain as installed for the remainder of the test.

9.46 External Cooling System Cleaning - Clean the external cooling system of either a new or used test stand, or a new flushing tank assembly. Clean the used test stand system periodically, typically before a reference test. Use the following procedure:
9.46.1 Prepare a cleaning mixture in the flushing tank (drawing RX-116924-C) by mixing Sequence IIIG test component cleaner (Warning - Corrosive. Health Hazard.) at 19 g per 1 L of water (see 7.4). Heat the mixture to 60 °C +/- 2.8 °C.

9.46.2 Circulate the mixture at 160 L/min flow rate for 30 min.

9.46.3 Immediately following step 9.46.2, thoroughly flush all system components with water at 60 °C +/- 2.8 °C.

9.46.4 Ensure that all low points in the system are drained after cleaning.

9.47 Engine Coolant Jacket Cleaning (Flushing) - After installing the engine on the test stand, chemically clean the engine coolant jacket to ensure the proper rate of heat transfer to the jacket coolant, according to the following procedure:
9.47.1 Connect the flushing tank to the engine so that the cleaning solutions enter at the coolant outlet adapter and exit at the front of the engine block (reverse flow only for flushing) through the water inlet adapter.

9.47.2 Connect the coolant outlet hose located at the front of the engine intake manifold to the flush cart return for this procedure.
9.47.2.1 Equip the coolant outlet hose connection at the intake manifold with a suitable 1/2-in. ball valve. Close this valve during the flushing portion of the procedure using the Sequence IIIG Test Component Cleaner. Open the valve during the water rinse portion of the procedure.

9.47.3 For the following segments of this cleaning procedure, minimize the elapsed time between steps in order to avoid rusting of the coolant jacket.

9.47.4 Remove the oil pan drain plug. Open the engine block petcocks and pass hot water 60 °C to 70 °C through the engine coolant jacket for 2 min. Check for coolant leaks around the intake manifold, front cover, rear cover, and oil pan drain plug. If coolant is leaking, take appropriate steps to stop the leak. If no leaking is evident, close the petcocks and fill the flushing tank and engine block with water to provide a total volume of 38 L to 45 L.

9.47.5 Energize the flushing tank heaters. Circulate water through the engine at a flow rate of 115 L/min to 130 L/min through the engine until the temperature of the water flowing out of the engine reaches 70 °C +/- 3.0 °C. Isolate the engine from the flush cart.

9.47.6 While the flush cart is isolated from the engine with water still circulating, add Sequence IIIG test component cleaner at 19 g/L of water (see 7.5.3) to the water in the flushing tank. Continue to circulate the mixture in the flush cart for 3 min to 5 min.

9.47.7 Circulate the mixture through the engine for 30 min.

9.47.8 Stop the circulation pump, open the engine block petcocks, and drain the contents of the engine and flushing tank into a suitable container (see Note 7).

NOTE 7 - Before disposal, the drained material should be neutralized according to applicable local and federal hazardous material guidelines.

9.47.9 Open the ball valve on the coolant outlet hose on the intake manifold. With the engine block petcocks closed, flow hot tap water through the engine and flush cart system for 2 min to 5 min. The water flowing through the engine during this step shall make a single pass through the engine and flush cart. Continue flowing water through the engine until the pH of the water flowing out of the engine is neutral. Check the pH of the rinse water at the return port in the flush tank (see Note 7).

9.47.10 Immediately after neutralizing the engine block in 9.47.9, open the block petcocks and drain all flush water.

9.47.11 Disconnect the flush cart plumbing and remove any trapped water in the intake manifold plumbing by blowing compressed air through the coolant outlet on the rear of the engine block.

9.47.12 Connect the engine to the external engine cooling system.

9.47.13 Immediately charge the engine jacket with coolant.

9.48 Coolant Charging - Charge the engine jacket with the specified coolant (see 7.4) according to the following procedure:
9.48.1 To preclude contamination of the coolant system with water, install low-point drains and eliminate all traps in the system. Drain all water in the system.

9.48.2 Use a charging adapter installed between the external cooling system and the engine.

9.48.3 Completely fill the engine jacket and cooling system with coolant (see 7.3). Fill the engine coolant jacket before filling the condenser system.

9.48.4 Charge the condenser coolant system immediately after charging the engine cooling system.

9.48.5 Operate the circulating pumps to aid in the removal of air and consequently decrease the time to achieve clarity of the coolant. During this period, operate any proportioning valves in the coolant system several times.

9.48.6 Until the test is started, circulate the coolant at a temperature of 48.9 °C +/- 2.8 °C and a flow rate of 160 L/min. Start the test no later than 6 h after step 9.48.5.

9.49 Test Oil Charging - Charge the engine with the test oil as follows:
9.49.1 Install a new oil filter OHT3F-057-3.

9.49.2 Add an initial fresh test oil fill of 5.50 L through the rocker-cover oil-fill cap using a flask that is calibrated to Class A standards, via a National Institute of Standards and Technology (NIST) traceable standard.

9.50 Engine Oil Pump Priming - Prime the engine oil pump according to the following instructions:
9.50.1 With the harmonic balancer and front half of the oil pump drive gear OHT3F-036-1 removed, use a suitable high torque drill motor rated at (7 to 9) A at 2400 r/min (no load) for driving the oil pump drive tool OHT3F-038-1 rotating the gerotor oil pump in a clockwise direction (viewed from the front of the engine) for 2 min after indication of oil pressure. The Dewalt model DW515 has been found suitable for this application.

9.50.2 Replace the front half of the oil pump drive gear and the harmonic balancer and torque the harmonic balancer to 150 N·m + 76°.

9.50.3 Connect the crankcase pressure line and oil sample valve fittings in preparation for testing, and proceed with the initial run (see 11.14).