Front Of Engine Oil Leaks On
                                       1991-92 GM 1.9L Saturn Engines

AERA machine shops have reported engine oil leaks near the front crankshaft oil seal on 1991-92 GM 1.9L Saturn engines.  This leak is between the seal and the pulley or damper.  Both SOHC and DOHC engines have been affected from what appears to be excessive porosity of the pulley or damper.

If the leak is determined to be in this area on 1991-92 engines, pulley/damper and seal  replacement may be necessary.  A replacement pulley for the SOHC engine is available under  Part #21000756.  The DOHC engine requires a different pulley with the Part #21006009.  Both engines use the same oil seal Part #21000707.  Depending on the extent of the porosity, it may be possible to install a thin-wall sleeve on the pulley.

Dampers and pulleys built after VIN Code # NZ143903 in 1992 have been machined to provide a better sealing surface. 

                                                                          The AERA Technical Committee

                               Engine Oil in the Cooling System On
                                   1991-97 GM 1.9L VIN 8 & 9 Engines

AERA members have reported engine oil in the cooling system on 1991-97 GM 1.9L VIN 8 & 9 engines. Only Saturn vehicles equipped with this SOHC engine may encounter this condition. Symptoms of this condition may include engine overheating. The owner may also comment on continuously adding engine oil to the crankcase.

The source of this condition may be located in the rear of the cylinder head at the number four and five camshaft journal bores and areas. Cracks located in 
this area (See Illustrations Below) of the head may allow engine oil to mix with engine coolant. These cracks may have been caused by irregularities during 
manufacturing of the cylinder head. Pressure testing of the cylinder head with the camshaft installed, may not always reveal a leak. Removal of the camshaft
is necessary to successfully pressure test this cylinder head.

AERA members have successfully repaired some of the cracks in the cylinder heads. If the cracking of the cylinder head is beyond repair, Saturn recommends 
replacing the cylinder head. Replacement of the head has been covered under the normal Saturn warranty conditions.
                 
                   Year Model               Head Gasket                       Head Part Number
                                                       Part Number
                 
                    1991-94                      21008324                                   21008232
                       1995                         21007332                                   21007138
                     1996-97                      21007332                                   21006837
  
                                                                              The AERA Technical Committee

                                                  Oil Consumption On
                                       1990-92 GM 1.9L Saturn Engines 

AERA members have reported instances of oil consumption on 1990-92 GM 1.9L Saturn engines.  GM considers excessive oil consumption on this engine to be more than one quart of oil (.95 liter) per 3,000 miles (4827 km).  This condition may result from oil passing by worn valve stem seals into the combustion process.

If cylinder compression values are within the normal range of 185-205 psi (1,276-1,344 kPa) and valves are not damaged, installing new seals Part #21006516 should solve this problem.  It is also possible to install new valve seals without removing the cylinder head from the block with the proper tools.

If cylinder compression values are lower than normal, performing a cylinder leakdown test may indicate further engine disassembly is required.

Another consideration for oil consumption is a problem with the positive crankcase ventilation system, which is described in AERA Technical Bulletin TB-791.

                                                                           The AERA Technical Committee

                                                Cylinder Head Bolt Caution On
                                                2001-02 GM 2.2L VIN F Engines

The AERA Technical Committee offers the following information regarding a cylinder head bolt caution on 2001-02 GM 2.2LVIN F engines. Apparently previously published Saturn service manuals have the incorrect torque listed. 

If the published torque is used, cylinder head bolt breakage may occur. Previously published head torque had an additional 185° added to the torque. The correct torque for this engine should be 22 ft/lbs + 155°. Any time that the cylinder head is taken off of this engine, cylinder head bolts must be replaced. Follow the torque sequence provided below in Figure 1. 

 22 ft/lbs + 155°
Figure 1. Cylinder Head Bolt Torque Sequence.

                                                                         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

                                               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

                                        Cylinder Head Specifications on
                                              Case 207 Diesel Engines

The following cylinder head specifications should be considered when remanufacturing Case Model 207 diesel engine cylinder heads.

The minimum cylinder head thickness has been established at 3.968 with a new head measuring 4.000 +/- .005.  Heads are measured from the deck surface to the rocker cover rail.

Valve recession should be checked and adjusted if necessary to a maximum recession of .015, below the deck surface, for both intake and exhaust valves.  Valves on new cylinder heads are generally flush with a +/- .005 tolerance.

                                                                       The AERA Technical Committee