Swapping Engines


Ever since the introduction of emission controlled engines there
has been much discussion on how this affects swapping engines
among different vehicles and/or model years.  

According to the Federal EPA the following facts apply:
o            Every vehicle sold in the US has an engine or engine-chassis
design which has been certified by the EPA.  This certification
has been achieved prior to production of the vehicle and is based
on a Federal Test Procedure (FTP).

o            EPA policy states that any modifications to a certified
configuration would be considered tampering unless there is a
reasonable basis for knowing that vehicle emissions are not
adversely affected.  Use of the FTP may be necessary to make this
determination.  However, EPA's tampering enforcement policy
states: ... the permanent removal or disconnecting or blocking
of any part of the original system primarily installed for the
purpose of controlling emissions will be presumed to affect
adversely emission performance ...

o            Any engine being installed in a vehicle must provide at
least the same amount of emission controls as the certified
configuration for the model year. For example:  A 1984 Chevrolet
Caprice was available with either a 5.0 or 5.7L (305 or 350 CID)
engine.  If one engine is replaced with the other, all of the
related emission control devices, including the computer, will
have to be changed in order to be in compliance with EPA.

o            Installing a new engine in an earlier design vehicle is
permitted as long as all related components from the new model
year are used.  

o            Installing an older engine in a newer design vehicle is not
permitted.  

o            Installing any engine without reinstalling all of the
emission control equipment, the way it originally came from the
manufacturer, is considered tampering.  This also includes
modifications to the exhaust system, such as changing from single
to dual exhaust unless there was such a certified configuration. 
In each case the installation facility may be cited by the EPA.

o            Replacing a diesel engine with its gasoline counterpart must
include installation of all of the emission control equipment. 
Even the unleaded gasoline only restrictor must be installed in
the fuel tank inlet.

o            The EPA does not accept an exhaust gas analyzer test in lieu
of their FTP test for non-certified configurations.  It is the
responsibility of the installation facility to have the vehicle
tested according to the FTP.


                                                                    
The AERA Technical Committee


October 1990 - TB 707

##END##

                       Crankshaft Thrust Wear On
                      1994-96 GM 4.3L V-8 Engines


AERA members have reported excessive crankshaft thrust wear on 1994-
96 GM 4.3L V-8 engines. This engine is used in Chevrolet Caprice
cars and many of those are in taxi-cab fleets. These cars often
obtain high milage in a short period of time and many are currently
being rebuilt. AERA members have noticed abnormal thrust wear on the
crankshaft cast #10168568, as those engines are disassembled.

In some instances, those vehicles may have already required
transmission service and have had the torque convertor replaced. GM
engineering has expressed to AERA that the torque convertors used in
these vehicles are not the same as previous designs. This
application requires additional internal reinforcement of the torque
convertor. If a torque convertor for a different application is
installed into this vehicle, the converter may expand and cause the
crankshaft to be forced forward. The torque convertor for this
engine, Part #24202174, is also used in high performance engines.

                                         The AERA Technical Committee


April 1996 - TB 1332


##END##

                                      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

                                         Main Bearing Saddle Repair Kits

The Cummins Engine Company has made main bearing saddle repair kits available for several engines.  These kits can be used to salvage cylinder blocks when a main bearing has spun and the main bearing saddle has been damaged.

Each kit contains an 1/8 drill bit, two hold down bolts (one for the lock ring and one for the other side of the saddle), a quantity of rivets and the appropriate number of repair sleeves.  Semi-finished or good used main bearing caps are also needed to complete the repair.

A main bearing saddle can be successfully repaired by following this procedure.
                                                                                                                            Remove the main bearing cap from the saddle to be repaired.  Using the appropriate align bore tooling remove .050 of material out of the saddle.  This will enlarge the main bearing bore by .100.

Clean the saddle and lock tang area.  Install the repair sleeve and align the lock tang slot of the sleeve with the one in the block.

From the repair kit, install the washer marked L on the lock tang side of the saddle.  Install the second washer on the opposite side.  Install the hold down screws and torque to 20 lbs.ft. (Figure 1).

Mount the 1/8 drill bit in a right angle drill, so that the drill extends 1/4 beyond the chuck jaws.

Using the 4 holes in the repair sleeve as a guide, drill through each of the holes into the saddle.  The proper hole depth is achieved when the chuck jaws contact the repair sleeve.

Clean the 4 holes and install the supplied rivets (Figure 2).  Peen the rivets until they are flush with the repair sleeve.

Remove the temporary hold down bolts and trim the ends of the repair sleeve so they are flush with the main bearing saddle.

Clean the main bearing bolt holes and install a good used or semi-finished main bearing cap.  Torque the main bearing bolts to specifications.

Using the appropriate align boring tools, refinish the main bearing housing bore to specifications.  Approximately .050 of material should be removed from the repair sleeve.
                                                                             
Main bearing bore repair kits or sleeves may also be available from several aftermarket sources.

                                                                        The AERA Technical Committee

                          Overheating Of Engines With Electric Cooling Fans

Ever since gasoline prices have shot up, vehicle manufacturers have downsized cars and their engines.  One of the best ways of making a car smaller is to turn the engine sideways under the hood.  This has instituted the use of one or more electric cooling fans to move air through the radiator.  Diagnosing overheating conditions on engines with electric cooling fans requires a few extra steps to ensure that the electrical control system for the fan is operating properly.

o    Perform all of the tests associated with normal
     installations, for example:  check antifreeze level,
     thermostat, water pump and hoses.

o    Check that the cooling fan is moving air through the
     radiator.  With the fan turned on air should never blow out
     through the front of the vehicle.  If there is more than one
     fan, be sure to check both.  It's possible for the
     electrical leads to be reversed during installation causing
     the fan to move air in the opposite direction.

o    If the vehicle is equipped with two fans, be sure that both
     of them work.  If the vehicle is equipped with air
     conditioning, one of the fans may only operate when the air
     conditioning is on.  Consult the service manual if you are
     not sure.

o    Fans are controlled by a temperature sending unit.  Check a
     suspected faulty sensor by bridging the two connections.  If
     the fan comes on, then the sensor is at fault.

o    Verify that the fan comes on at the temperature listed in
     the service manual.  Replace the sensor if the proper
     temperatures are not maintained.

For additional information see AERA Technical Bulletins: TB 706,
SB 158 & SB 137

                                                                         The AERA Technical Committee