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

            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

                                          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

                                   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
----------------------------------------------------------------
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

                       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

                            Flywheel Specifications for Case/IH Tractors

The following chart of new flywheel specifications may be used when surfacing or machining flywheels on Case/IH agricultural and industrial tractors.

Engine    Machine Application       Dim. A                 Dim. B

C-60      Cub, Lo-Boy                         1.625                 0.013
C-123     200, 230, 240 Tractors        1.182                 1.188
C-123     Flywheel #372436R11         1.375                 1.188
C-123     Flywheel #635094R11         1.425                 1.125
C-135     330, 340 Tractors                 1.115                 1.188
C-135     404 Tractor                           1.182                 1.188
C-135     T & TC5 w/CRPTCO             1.425                1.125
BC-144    B-414, 3414 Tractors          1.156                 1.334
BC-144    Flywheel #3047594             2.075                  N/A
BD-144    B-275 Tractor                      1.188                 1.313
C-146     660, 770, 780 Sprayer           0.872                0.800
C-146     424 Tractor                            1.293                1.344
C-146     500 Crawler, single plate     2.050                 N/A
C-146     500 Crawler, dual plate        1.425                 1.125
C-153     504, 2504, 3514 Tractors      1.115                 1.188
C-153     444, 2444, 4000 Forklift         1.293                 1.344
BD-154    B-414 Tractor                       1.156                 1.344
D-155     500C Crawler                        3.216                  N/A
C-157     454, 2400 Tractors               2.000                  1.443
D-166     330, 340 Tractors                 1.115                  1.188
C-169     300 Tractor                           1.187                  1.187
C-175     300, 350 Tractors                 1,187                  1.187
C-175     3514 Tractor                        2.719                   1.188
C-175     454, 464, 2400 Tractors      2.000                   1.443
D-179     454, 484 Tractors                2.494                   1.443
D-188     504, 2504, 3514 Tractors    1.115                   1.188
C-200     544, 2544, 8000 Forklift       2.719                   1.188
C-200     3500 Series A                      2.000                   1.443
          S/N 28344 & above
C-200     574, 674, 2500, 3500 Series A   2.808            1.443
          S/N 28343 & below
C-221     460, 606, 2606, 3616 Tractors   2.719            1.188

C-221     3616 Tractor S/N 49943 & above 2.470        1.437
D-236     460, 606, 2606,                      2.719                 1.188
          3616 S/N 1772 & below
D-236     3616 S/N 1773 & above       2.470                 1.437
D-239     574, 2544, 3544 Tractors      2.460                 1.181
D-239     574, 674, 2500, 3500 Tractors 2.494              1.443
D-239     Flywheel #3144211R91        2.204                  1.437
C-248     M, 6 Series Tractors            1.374                  1.406
C-263     506, 560, 606 Tractors          3.032                  1.406
C-263     706, 2706 Tractors                1.624                  1.406
C-263     656 Tractor                            2.470                  1.437
C-264     Super M, 400 Tractors          1.374                  1.406
D-264     Super MD, 400 Tractors       1.374                  1.406
C-281     400, 450, Super M, Super 6  1.374                  1.406
D-282     560 Tractor                            3.031                  1.406
D-282     660, 706, 2706 Tractors        1.729                  1.406
D-282     656 Tractor                            2.470                  1.437
C-291     666 Tractor                            2.470                  1.437
C-291     9000 Forklift                           1.694                  0.120
C-301     806, 826, 856 Tractors          1.624                  1.406
D-310     706, 756 Tractors                  2.362                  1.406
D-312     666 Gradall                           3.063                   1.437
C-335     W-9, WR-9, WR-9S               1.625                   .500 above
          S/N 501-1439                                                   backplate mounting
C-335     W-9, WR-9, WR-9S               1.625                   1.438
          S/N 1440 & up                       
D-335     WD-9                                      1.625                  .500 above
          S/N 501-1439                                                   backplate mounting
D-335     WD-9                                     1.655                    1.438
          S/N 1440 & up 
C-350     W-9, WR-9, WR-9S,              1.655                    1.438
          600, 650 Tractors
D-350     Super WD9, 600, 650 Tractors 1.655               1.438
D-358     826, 2826 Tractors             2.362                       1.406
D-360     766 Tractor                         1.594                       1.406
D-361     806, 2806 Tractors             1.594                       1.406
DT-361    1206, 21206 Tractors       1.562                        1.938
DT-407    1256, 456, Tractors          1.562                        1.938
                 21256, 21456
DT-407    856, 2856 Tractors           1.594                       1.406
DT-414    966 Tractor                        1.594                      1.406
DT-414    1096 Tractor                      1.562                      1.938
DT-414    815, 915 Tractors              1.562                      1.406
DT-429    4100, 4156                         1.562                       1.938
DT-436    1466 Tractor                      1.562                      1.938                                   
DT-466    4366 Tractor                      1.627                       1.938
DV-550    1468, 1568 Tractors          1.792                       1.938
DV-800    4568, max. stock removal .063 1.437             2.938

Specification `A' is measured from the crankshaft mounting flange surface to the clutch friction surface.  Specification `B' is measured from the pressure plate mounting surface to the clutch friction surface.

                                                                      The AERA Technical Committee

                                    Coolant In The Engine Oil Supply On
                                          Navistar 6.9L Diesel Engines

AERA members have reported several instances of coolant entering
the engine's lubricating oil supply on Navistar 6.9L diesel engines.

The coolant leak has been traced to a crack in the #6 cylinder (third cylinder on the left side) lifter bore area of the cylinder block.  Most of the time the crack can be seen with the naked eye on the bottom side of the lifter bores near the piston
cooling nozzles.  With the engine off and the cooling system pressurized, in some cases, coolant will actually flow from the piston cooling nozzle itself.  

Pressure testing the cylinder block is one way to easily identify cracks in this area.  Don't forget to check both the top and the bottom of the lifter bore area.  Unfortunately there is no repair for this fracture of the cylinder block.

For additional information see AERA Technical Bulletin: TB 544

                                                                       The AERA Technical Committee

                                      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