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ALTERNATIVE CAM BEARING FOR 3406E CATERPILLAR ENGINES |
Alternative Cam Bearing For
1993-2003 Caterpillar 3406E Diesel Engines
The AERA Technical Committee offers the following information regarding an alternative cam bearing for 1993-2003 Caterpillar 3406E diesel engines. This oversize outside diameter (OD) bearing can be used for salvage operations when cam bores are worn.
The bearings can be used at any particular location in the overhead camshaft (OHC) cylinder head and are offered in a .010 (.25 MM) and .030 (.76 MM) oversize. AERA members have reported an oversize bearing also being used on original equipment engines. Use the chart below to determine the bearings required to replace or salvage cam bores.
Housing Bore Part Number Bearing Size
3.5813-3.5829" (90.965-91.005 MM) 2165582 Standard
3.5911-3.5927" (91.215-91.255 MM) 2170751 .010 (.25 MM) O/S
3.6108-3.6124" (91.715-91.755 MM) 2170752 .030 (.76 MM) O/S
AERA is unaware of a source other than Caterpillar for these bearings.
The AERA Technical Committee |
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CYL HEAD OIL GALLERY MODIFICATION |
Cylinder Head Oil Gallery Modification On
1976-85 Volvo 2.1 & 2.3L Engines
AERA members have reported a cylinder head oil gallery modification for Volvo 2.1& 2.3L engines. To enhance upper engine oiling, simply increase the diameter of the oil gallery hole to .563 (14 mm). To do so, requires the removal of the cylinder head and a drilling operation.
This engine design may allow sludge to accumulate in the oil gallery over a period of time if poor oil maintenance exists. To reduce the possibility of a seized camshaft from lack of lubrication at start-up, the following modification should be made to the cylinder head.
1. Remove cylinder head and locate the oil gallery feed hole on
the head gasket surface as shown in illustration below.
2. Obtain a .563 (14 mm) drill, and drill perpendicularly down
a distance of 1.770 (45 mm).
3. Do all other machine operations and clean thoroughly before
placing back in service.
4. Clean crankcase ventilation system and verify those
components are the manufacturer's current design.
The AERA Technical Committee |
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CRANKSHAFT/CAMSHAFT SEAL OIL LEAKS |
Volvo Crankshaft/Camshaft Seal Oil Leaks
Possible oil leaks around the crankshaft, camshaft or other engine gaskets may be due to a clogged flame trap in the PCV system. This does not seem to happen on turbocharged models.
The plastic Y-shaped flame trap is located in the PCV apparatus and may become clogged if engine oil is infrequently changed. Low grade or inexpensive oil may also cause stoppage which allows internal crankcase pressure to build, thus forcing an oil leak. In some cases, the pressure will force the oil dipstick to pop out.
A clogged flame trap should either be cleaned or replaced, says Volvo, and normal maintenance calls for routine cleaning of the trap every 15,000 miles.
The AERA Technical Committee |
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REVISED CONNECTING ROD |
Revised Connecting Rods On
1988-89 Volvo 2.3L B230 Engines
AERA members have reported connecting rod failures in 1988-89 Volvo B230 engines. Rod failures include both bending and actual breakage. Because of the frequency of these failures, Volvo has redesigned the connecting rod for additional strength (See illustration). Engines manufactured as of the 1990 model year use the revised connecting rod.
The revised rod features a thicker beam and has increased in weight by 40 grams. The revised rod should only be installed in complete sets of four, Volvo Part #0271451-7 (four matched rods). Substituting a revised rod, Volvo Part #3531260-2, for the former design will cause an out-of-balance condition and possible engine failure.
The AERA Technical Committee |
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CYLINDER BLOCK & CRANKSHAFT CHANGES |
Cylinder Block & Crankshaft Change On
Volvo 1988 2.3L B230 Engines
Volvo Motors has changed the cylinder block and crankshaft on 1988 and later 2.3L B230 engines. The changes are related to the crankshaft main journal size and thrust location. Volvo also identifies 1988 and newer blocks by stamping K externally on the front timing case.
Crankshaft main journal diameters have increased in diameter to 2.4798-2.4803 (62.987-63.000 mm). The thrust bearing has been relocated to the rear main and uses a flanged type bearing. The thrust length on the crankshaft was also increased to a length of 1.398 (35.5 mm). Connecting rod journals remain unchanged at 1.9285-1.9293 (48.984-49.005 mm) in diameter.
Revising the crankshaft required the block main bearing bores be increased to 2.6378-2.6383 (67.000-67.013 mm) in diameter.
Years Main Journal Rod Journal Thrust Main Brg.
Used Diameter Diameter Location Housing
& Length Bore
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1985-87 2.1648- 1.9285- 1.142 2.3228-
2.1654 1.9293 @ #3 2.3236
1988-92 2.4798- 1.9285- 1.398 2.6378-
2.4803 1.9293 @ #5 2.6383
The AERA Technical Committee |
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ROD SIDE CLEARANCE |
Crankshaft & Connecting Rod Assembly Caution For
1980-1984 2.3L AQ151 & AQ171 Volvo Marine Engines
The AERA Technical Committee offers the following information regarding a connecting rod and crankshaft assembly caution for 1980-1984 2.3L AQ151 & AQ171 marine engines. This information is most useful when engine disassembly and reassembly personnel are different people.
These engines use a crankshaft and connecting rod combination that appears to be ?not right" when the connecting rods are assembled to the crankshaft. The reason for this concern is expressed in the photo below, as it appears there is excessive rod side-play. The view shown below is normal even though it shows approximately .125" clearance on each side of the rod.
Previous service information has been reported to be unclear as to the allowable side play for connecting rods. Illustrations? showing ?normal" rod side play is in most manuals has further confused the issue.
Volvo refers to this extra rod side clearance as a ?low friction" design and they use it in several of their automotive engines as well.
The AERA Technical Committee |
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COUNTERBORE REPAIR FOR 8.3L SERIES ENGINES |
Cracked Counter Bore Repair For
1985-2000 Cummins 8.3L, C Series Engines
The AERA Technical Committee offers the following information regarding a cracked counter bore repair on 1985-2000 Cummins 8.3L C Series diesel engines. Some engine blocks may have extreme wear or cracks in the counter bore where the sleeve flange rests in the block.
One possible repair of this condition involves installing cylinder liner shims that can be installed under the sleeve. These shims can be purchased from Cummins and range in thickness of .010-.040 as shown in the table below with the corresponding part numbers. In most instances, machining the counter bore ledge (C below in Figure 1) is required when wear or cracking is evident. In those instances it is recommended to remove only the minimal amount of material to allow using the thinnest shim. NOTE: Use only one shim.
Clean all deposits and debris from the sealing surface A, B and C shown in Figure 1 before installing each shim. Use Scotch-Brite® and a cleaning solvent to polish the surfaces. Due to critical machined tolerances, care must be taken not to remove any additional material from the cylinder block.
Cylinder Shim Part Number Shim Thickness
3924445 .010 (.25 mm)
3924446 .015 (.38 mm)
3924447 .020 (.51 mm)
3924448 .030 (.76 mm)
3924449 .040 (1.00 mm)
The AERA Technical Committee |
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NEW CYLINDER LINER O-RINGS |
New Cylinder Liner O-Ring Seals On
Cummins NH/NT 6 Cylinder Engines
Cummins Engine Company has released new O-ring seals for the cylinder liners in NH/NT 6 cylinder engines. The new seals are made of an EP material and have a smaller diameter cross-section.
The new seal replaces both the old center seal #3008998 and the old lower seal #183049. The new seal carries Cummins part #3032874 and is black in color with one blue dot.
The new O-ring seals are not to be intermixed with the former seals on the same liner. Cylinder liner deformation will result. You can use the former seals and new seals in the same engine as long as they are used in the correct combinations on each liner. The illustration below shows the correct combinations.
The AERA Technical Committee |
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OIL IN COOLANT |
Oil in Cooling System on
VW 1.5L & 1.6L Diesel Engines
AERA members have reported instances of engine oil in the cooling system on VW 1.5L diesel engines. According to AERA sources, the problem is related to a crack in the cylinder head bolt hole located near the oil gallery feeding the cylinder head.
The oil feed gallery in the block is located on one side of the center head bolt hole and a coolant jacket is on the opposite side of the bolt hole. Pressurized engine oil is diverted through a slot in the head gasket and is feed up the side of the head bolt to the cylinder head. The oil also follows the bolt back down to the bottom of the bolt hole. Should the crack in the head bolt hole extend to the coolant jacket, oil can mix with engine coolant.
This problem is generally found on engines equipped with 11mm head bolt holes. Later design engines utilize 12mm head bolts and do not exhibit this defect. At the time of this writing no successful repair procedure is available.
The AERA Technical Committee |
