| 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## |
| REVISED PISTON ASSEMBLY FOR 1990 |
Revised Piston Assembly
1990 Navistar DT-466 Engines
Navistar International has revised the piston on 1990 DT-466 engines. The piston introduced for the 1990 model year features an increase in depth and volume of the combustion chamber bowl. In addition, pistons used in the E270 engine have a .030 radius around the entire combustion chamber bowl edge.
The use the following chart to select the appropriate piston:
Model Piston Piston
Year Engine Part No. Model No.
1989 DT-466 Federal & CA 1 810 527 C2 466T4
DTA-466 California
1989 DTA-466 Federal 1 811 737 C2 466T5 w/radius
bowl
1990 DT-466 E185 & E210 1 815 345 C1 466T4
DTA-466 E220 & E245
1990 DTA-466 E270 1 815 330 C1 466T5 w/radius
bowl
The piston's production part number and model identification number are stamped on the crown of the piston (see illustration below).
The AERA Technical Committee |
| CYLINDER HEAD SPECIFICATIONS |
Cylinder Head Specifications For
Detroit Diesel Corporation 60 Series Engines
AERA member machine shops should consider the following specifications when remanufacturing DDC 60 Series cylinder heads.
The cylinder head deck face should be flat within .005 (.120mm) front-to-rear and .003 (.076mm) side-to-side. Resurfacing of the cylinder head is recommended if these specifications are not met. DDC has set the cylinder head height at 6.5019-6.4719 (165.15-164.388mm) when measured from the deck surface the top rail (Figure 1). This permits a maximum stock removal of .030
(.762mm) off the cylinder head. Due to the overhead camshaft design of this engine, the combined stock removal from the cylinder head and cylinder block may not exceed .030 (.762mm). DDC recommends a deck surface finish of 90 Ra for proper sealing.
When the cylinder head has been resurfaced the injector tube bore land width needs to be checked (Figure 2). If necessary, countersink the injector bores to restore a land width of .040-.080 x 45o (1.0-2.0mm x 45o). Always install new injector tubes when a cylinder head has been resurfaced.
Valve recession has been established at .055-.067 (1.4-1.7mm) when measured relative to the cylinder head deck surface (Figure 3).
Install the cylinder head and torque the head bolts using the sequence shown in Figure 4. Lubricate the bolt threads with oil and the bolt contact areas with International Compound No. 2 or equivalent. Tighten the head bolts in sequence to 185-210 lbs.ft. (250-285 Nm). Recheck each bolt to ensure that the
proper torque has been achieved.
For additional information see AERA Bulletin: TB 684
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 |
| NEW ROCKER ARM SHAFTS |
New Rocker Arm Shaft Assembly Released On
Navistar (International) 3.2, 5.0, 5.6 & 6.4L
(196, V-304, V-345 & V-392 CID) Engines
A new rocker arm shaft assembly is now available for the 196 and small V-8 engines. The new shaft assembly has 4 less rocker arm shaft support brackets per cylinder head than the previous shaft assembly.
The four support brackets and their mounting bolts are replaced by springs, new shorter nylon patch bolts and hardened flat washers to seal the previous support bracket mounting bolt holes.
This change was incorporated into production starting with the following engine serial numbers:
Engine Model Starting Engine S/N
V-304, 345, 392 1492201
V-304A, 345A 280934
4-196 59231
The new rocker arm shaft assembly is serviced in a kit. The .312- 18 UNC x .500 bolts with nylon patches which are included should be torqued to 155-190 in.lbs. (18-20Nm).
The AERA Technical Committee |
| REVISED CONNECTING ROD |
New Connecting Rod Assemblies On
Navistar (International) DT-466 &
DT/DTI-466B Diesel Engines
A new 45° split line connecting rod assembly with a revised piston pin oil reservoir has been released for DT-466 & DT/DTI-466B diesel engines. The new connecting rod assemblies, which are not shot-peened, replace the old 35° assemblies starting with serial #32813 for the DT-466 engine and serial #75957 for DT/DTI-466B. The thread length of the connecting rod bolts has been
increased from 1.12 (2.84cm) to 1.70 (4.32cm) to facilitate the new design.
Old and new rods can be intermixed for engines in the field. New con rod bolts (676679C2) can be used in old con rod bolts, but OLD BOLTS (676679C1) MUST NOT BE USED IN NEW CON ROD ASSEMBLIES.
The AERA Technical Committee |
| INCORRECT THERMOSTAT ON 6.9L DIESELS |
Caution On Using Correct Thermostat On
International 6.9L Diesel Engine Including
Those In Ford Vehicles
International Trucks reports that thermostats in 6.9L diesel
engines are being replaced with will fit replacements, which
may cause premature cylinder head gasket failure due to engine
overheating. The overheating occurs because a flat washer
secured to the end of the power pill obstructs the bypass and
normal coolant flow passage. See illustrations below.
(Insert 2 Illustrations)
The AERA Technical Committee
April 1984 - SB 111
##END## |
| REVISED OIL SEAL CARRIER & GASKET FOR 7.6 & 8.7L DIESELS |
Revised Oil Seal Carrier & Gasket For
2000-2003 Navistar 7.6L & 8.7L Diesel Engines
The AERA Technical Committee offers the following information regarding a revised oil seal carrier and gasket for 2000-2003 Navistar 7.6 and 8.7L diesel engines. The revised components have proven to provide more effective sealing. Anytime the previous design paper gasket and flat flange oil seal carrier are removed, the revised components are recommended for use.
The new-machined groove in the oil seal carrier gasket flange, for push-in place seal, is more effective for sealing. The push-in place seal will ensure accurate alignment during assembly and adequate clamp load on the seal. A machined surface has been added to the bottom of the carrier to ensure a proper sealing surface for the oil pan.
Parts are currently only available from Navistar International with Part #1815699C3 for the oil seal carrier and Part #1741974C1 for the seal carrier gasket.
The AERA Technical Committee |
| OIL LEAKAGE PAST CRANKSHAFT REAR MAIN OIL SEAL |
Severe Oil Leakage On
Navistar (International) V-304, V-345 & V-392 Engines
A limited number of V-304, V-345 & V-392 Navistar (International) truck engines have been built with the oil return hole in No. 5 main bearing cap omitted. The omission of the oil return hole will create a high pressure area resulting in oil leakage past the rear crankshaft oil seal.
If such a leak is found and normal seal life has not been realized, check the No. 5 main bearing cap for omission of the oil return hole. If the hole is omitted, remove the No. 5 main bearing cap and drill a 3/8 diameter hole into the oil return cavity as per illustration.
The AERA Technical Committee |
