| REVISED FLYWHEEL BOLT TORQUE METHOD |
Revised Flywheel Bolt Torque Method On
DDC 71 & 92 Series Engines
The AERA Technical Committee offers the following information on
flywheel mounting bolt torque for DDC 71 & 92 series diesel engines.
The flywheel mounting bolt torque turn method has been revised to
provide more consistent clamping load on the fasteners. DDC also
recommends replacing those bolts anytime the flywheel is installed.
Depending on the application, several different length bolts may be
used and the applied torque depends upon the length of the bolts.
All new bolts should have a small amount of International Compound
#2 applied to the bolt threads and underside of the bolt head, prior
to installation. Refer to the chart and illustration below to
determine the correct bolt torque and procedure.
Bolt Length Step 1 Step 2
Bolts 2.750 Long + less 50 ft/lbs. Turn 90-100^
Bolts Over 2.750 50 ft/lbs. Turn 150-180^
The AERA Technical Committee
June 1996 - TB 1352
##END## |
| INTERCHANGEABILITY OF CRANKS, CAMS & TIMING GEARS |
Caution On Interchangeability Of Crankshafts,
Camshafts & Timing Gears On
International DV-462, DV-550, DV-462, & DV-550B Engines
Note: The above engine models differ in designation only in that the later engines have a suffix B.
The suffix B engines are equipped with Holley fuel injection pumps and require Tufftrided gear trains.
In manufacture it was found that the tufftriding process increased the bore diameters of camshaft and crankshaft gears to the point that there were insufficient interference fits when installed. Therefore, camshafts and crankshafts intended to be used in suffix B engines had to be manufactured with larger gear receiving diameters. It is for this reason they are not interchangeable.
Crankshafts and camshafts removed from or intended for DV-462 and DV-550 engines must not be used in conjunction with Tufftrided gear trains in engines with suffix B.
It is suggested that interference fits should be verified by measurement before applying timing gears. If the use of new crankshafts and camshafts is prohibitive, rebuilding of the gear receiving diameters is required to ensure proper interference fits.
In addition to the above, on all suffix B engines the camshaft gear nut torque has been increased from 100 to 200 ft.lbs.
Crankshaft pulley nut torque has been increased from 150 to 325 ft.lbs.
The AERA Technical Committee |
| CYLINDER HEAD BOLT TORQUE CHANGES |
Cylinder Head Bolt Torque Specification Change
And Revised Tightening Procedure On
International Truck 400 Series Engines
A new cylinder head torque of 225 N·m (165 ft-lb) has been
adopted for proper assembly of the new style cylinder head bolts
with integral washers as well as old style head bolts with
hardened washers for International Truck 400 Series engines.
The former spec. of 203 N·m (150 ft-lb) should be disregarded for
head bolts with integral washers.
A revised tightening procedure has been developed for both old
and new style cylinder head bolts as follows:
Tighten cylinder head bolts using these steps:
1. Lubricate bolt threads, bolt head seating areas and washers
where applicable with clean engine oil.
2. Tighten bolts in 3 stages referring to the diagram below.
Stage 1 - Following sequence A, tighten bolts to 150 N·m
(110 ft-lb).
Stage 2 - Following sequence A, tighten bolts to 210 N·m
(155 ft-lb).
Stage 3 - Following sequence B, tighten bolts in rows to
225 N·m (165 ft-lb).
CAUTION: DO NOT BACK BOLT OFF. PULL UP TO TORQUE LEVEL
INDICATED.
(Insert 2 Illustrations)
The AERA Technical Committee
April 1983 - SPB 100
##END## |
| CYLINDER HEAD SPECS |
Cylinder Head Specifications on
Case 2870 Diesel Engines
The following cylinder head specifications should be considered when remanufacturing Case Model 2870, 674 CID diesel engine cylinder heads.
The minimum cylinder head thickness has been established at 4.898 (124.41mm). The cylinder head features a groove for fire ring retention that may need to be recut if the head has been surfaced. The groove should be .037 - .041 (.94 - 1.04mm) wide and .006 - .010 (.15 -.25mm) deep. The fillet of the groove should have a 10° chamfer.
Valve recession should be checked and adjusted if necessary to a maximum recession of .069 (1.75mm), below the deck surface, for both intake and exhaust valves.
The AERA Technical Committee |
| REVISED TOP COMPRESSION RING |
Revised Top Compression Ring On
Navistar DT-466 Engines
In order to reduce engine emissions and crankcase blow by,
Navistar International has revised the top compression ring on
1990 DT/DTA-466 engines.
The top compression ring is now plasma coated on the face and
directly replaces the former chrome plated ring for all engines,
including those manufactured prior to the 1990 model year.
Intermixing of plasma coated and chrome plated rings in the same
engine is acceptable.
The revised ring can be identified by its foggy/grey appearance
and a white Dykem stripe. The former ring is bright in
appearance and is marked with a blue Dykem stripe. Markings
found on the side of the piston ring must be installed facing up
(see illustration).
The revised ring is only available as part of a piston ring
package which carries Part #1 810 358 C94 replacing Part #1 810
358 C93.
The AERA Technical Committee
July 1991 - TB 790
##END## |
| ENGINE KNOCK ON XJ6 & 12 CYLINDER ENGINES |
Engine Knock on Jaguar 4.2L Engines
Diagnosis of an engine knocking noise on XJ6 and 12 cylinder Jaguar engines should start by checking the crankshaft pulley for looseness. A loose pulley bolt could cause such a noise that may decrease as the engine reaches operating temperature.
The crankshaft pulley bolt torque is 150 lbs.ft. Be sure to lock
down the crankshaft or crankshaft pulley before attempting to
torque the bolt.
The AERA Technical Committee |
| DISK BRAKE ROTOR SURFACING RECOM. FOR GM FWD VEH. |
Disk Brake Rotor Surfacing Recommendations on
1982-89 GM Front Wheel Drive Automobiles
General Motors has released the following recommendations when
refinishing rotors on 1982-89 FWD automobiles.
When it has been determined that a disk brake rotor needs to be
refinished, either due to nonparallelism, runout or scoring in
excess of .015, it is important to achieve a 10-50 micro-inches
nondirectional swirl pattern finish.
Brake lathes should be set accordingly:
Rough Cut Finish Cut
Spindle speed 150 rpm 150 rpm
Depth of cut .005 .002
Tool cross feed/revolution .006-.010 .002 max.
Furthermore improve the surface finish of the newly surfaced
rotor by dressing it to a nondirectional swirl pattern using a
120 grit sanding disk power tool. Most brake lathe manufacturers
offer such an attachment for their machines. Always use a
vibration damper whenever cutting rotors on a brake lathe.
Compare the finish of your rotor with a new factory unit when
possible by dragging a fingernail across the surface of the
rotor. You should be able to achieve the same finish.
The AERA Technical Committee
November 1988 - SB 162
##END## |
| REVISED CONNECTING ROD CAP SCREWS ON E-7 ENGINES |
Revised Connecting Rod Cap Screws On
Mack E-Tech & E7 PLN Engines
AERA members have reported a revised connecting rod cap screw on Mack E-Tech & E7 PLN engines. This change occurred during production of these engines beginning September 14, 1999.
The fully threaded shank identifies this new cap screw. Previous connecting rod cap screws had a long neck down shank as shown at the top in Figure 1. As a positive means of identification, the part number suffix can be found on the head of each cap screw as well.
The two 14mm connecting rod cap screws shown in the lower portion of Figure 1 are to be used with connecting rods that have alignment sleeves in the rods. The 211M & 212M on the head of the bolts identifies them. The 16mm cap screw is used on early E7 PLN engines having connecting rods without alignment sleeves and are identified by the 24M on the head of the bolt.
To provide strict control of torque on these rods, an angle torque method has been added to the two 14mm cap screws. Torque values for the three connecting rod cap screws are as follows:
· 396GC24M ? 150 ft/lbs
· 396GC211M ? 30 ft/lbs + 90°
· 396GB212M ? 30 ft/lbs + 90°
The AERA Technical Committee |
| REVISED PISTON ASSEMBLY FOR 7.3L DIESEL ENGINES |
Revised Piston and Ring Assembly On
Navistar 7.3L Diesel Engines
Navistar International has revised the piston and ring assembly for their 7.3L engines used in Ford light and medium duty trucks among others. The new pistons and rings are used in all engines manufactured as of serial number 598754. Prior engines use the former designs. The new assembly may be used in sets to update older engines when they are being remanufactured.
The revised piston features a taller top ring and oil control ring groove to accommodate the new plasma ring set. Since the former design rings will fit into the new piston, a mix-up is possible. However, loss of oil control and poor engine performance may result.
Revised Design
Bore Piston & Ring Ring Set Stamped No. on
Size Assembly Part # Part # Piston
STD 1 813 167 C91 1 813 171 C91 1 813 154 C1
.010 1 813 168 C91 1 813 172 C91 1 813 155 C1
.020 1 813 169 C91 1 813 173 C91 1 813 156 C1
.030 1 813 170 C91 1 813 174 C91 1 813 157 C1
Former Design
Bore Piston & Ring Ring Set Stamped No. on
Size Assembly Part # Part # Piston
STD 1 809 140 C91 1 809 146 C91 1 809 107 C2
.010 1 809 141 C91 1 809 147 C91 1 809 108 C2
.020 1 809 142 C91 1 809 148 C91 1 809 109 C1
.030 1 809 143 C91 1 809 149 C91 1 809 110 C1
At present there are no aftermarket sources available for either the former and revised piston or ring set. Furthermore, pistons are only available as an assembly that includes the wrist pin, lock rings and piston rings. Piston ring sets are serviced separately.
The AERA Technical Committee |
| NEW GASOLINE ENGINE OIL CLASSIFICATION SH |
New Gasoline Engine Oil Classification SH
The American Petroleum Institute (API) has released a new gasoline engine oil category SH. Engine oils meeting this classification should be used in all 1994 and later gasoline engines. This oil may also be used in gasoline engines
manufactured before the 1994 model year.
As EPA emission laws continue to evolve, manufacturers of gasoline engines have been forced to follow tougher standards with lower total emissions. As those demands continue, engine oils have also required improvements. The oil classification SH, provides better protection against rust, oxidation, sludge,
varnish and extended component life expectancy.
Oils branded with the SH moniker are tested under the tougher Engine Oil Licensing and Certification System (EOLCS). This new system requires oil to pass either the first time tested, or pass on an average score of multiple samples tested. Previously oils could continue to be tested until passing results were generated.
Oils that pass the SH test and meet Energy Conserving II (ECII) requirements may use a new starburst logo indicating certification from the International Lubrication Standardization & Approval Committee (ILSAC). This new symbol is designed to allow consumers to readily identify oils that conform to the latest engine oil standards. Along with the starburst logo, the familiar API donut will display the oil's viscosity and SH classification. Oils not conforming to the ECII requirements may display the SH rating without the new starburst symbol.
The AERA Technical Committee |
