Crankshaft Snout Failures On
                                              Mazda 1.6L (323) Engines

AERA members are reporting an unusual crankshaft snout failure on Mazda 323 vehicles equipped with 1.6L engines.  Sometimes the snout has completely broken away from the crankshaft, in others cracks were discovered during disassembly.

In this engine, the snout of the crankshaft supports an oil pump drive, timing sprocket and damper.  Fractures occurred between the damper and the oil pump drive area, at the bottom of the damper bolt hole (see illustrations).  

Consensus among AERA members has been that this type of breakage may be the result of insufficient wall thickness remaining after the bolt hole has been drilled and tapped (see illustration). This design was used in production until September 11, 1990. Later engines use a revised crankshaft with a larger diameter snout and a longer damper retaining bolt.   

While it is possible to use the revised crankshaft in earlier applications, many other components need to be changed as well. The alternative is to use a repair procedure that was developed by AERA member machine shops.

Remove the existing crankshaft snout and replace it with a solid piece of steel that is welded to the front of the crankshaft. The new, in-house replacement snout should be drilled and tapped for a smaller diameter bolt hole than was originally used.  The additional wall thickness and strength should avoid future
breakage.

Another repair method is to machine a stub shaft with male threads the same size (24mm x 1.50mm) as the existing crankshaft snout bolt hole.  On the pulley end of the stub shaft drill and tap a hole for a smaller pulley retaining bolt.  Drill and tap the remaining crankshaft bolt hole deeper, being careful not to
intersect the oil gallery of the front main.  Apply thread locking compound to the stub shaft and screw it into the crankshaft.

                                                                           The AERA Technical Committee

                                                Flywheel Specifications

The AERA Technical Committee suggests referring to the following flywheel
specification chart when re-surfacing flywheels.

Manufacturer        Type  Specification   Comments
--------------------------------------------------------------------
AMC                         C     .125           2.5L GM engine
Acura                       C     .030           Integra  1.6L engine
Acura                       C     .060-.070      Legand 2.7L engine
Audi                          S     .003-.005      4000 1.6L engine
Audi                          C     .982           Quatro 2.1L engine
Alfa Romeo             C     .878           2.0 & 2.5 L engine
BMW                        S     .013-.015      320i
BMW                        F     .984           Minimum thickness
Caterpillar, 3208     F     1.018          Minimum thickness
Caterpillar, 3208     C     1.060-1.070    
Caterpillar, 3406     C     2.937 +/-.005  #9N2646 Cast Number
Chrysler/Renault     S     .014-.021      1.4L engine
Chrysler/Mitsubishi C     .600-.605      2.0L DOHC, #9801 Cast Number
Chrysler                    C     1.00           3.7L engine
Cummins, B Series   F     1.260          Minimum thickness
Cummins, C Series   C     2.925          
Cummins                    C     2.937          Two piece clutch
Daihatsu                    C     .960-.965      6.5 clutch
DDC                           F     1.582          8.2L, Minimum thickness
DDC, 71 Series        C     2.937
Fiat                            S     .018           1600 Spider engine
Ford, Festiva            C     .020           1.3L engine
Ford, Probe              S     .020            2.2L engine
Ford, Falcon             C     1.00           L-6 engines
Ford/Mazda              C     .285           Courier, 1.8 & 2.0L engines
Ford                           C     .310
Ford, Ranger            C     .003           V-6  engines
Ford Truck, 6.1L       F     1.005          Min. thickness, 
                                          c/mount to fric/pad
Ford Truck                C     1.500          478 & 534 CID Truck
Ford Truck                F     .965           New Thickness
Ford Truck                F     1.410          6.9L Diesel, Minimum thickness
Ford                          C     1.140-1.160     Model A 
GM, GEO                  C     .787           Storm
GM, GEO                  C     .105           Metro, 3 cyl. engine
GM, Chevette           C     .018-022
GM, Brazilian OHC   F     .750           New Thickness
GM, Luv Truck         C     .015
GM                            C     .125           2.5L, & Vega
GM, Buick                C     .125           V-6 engines
GM, Buick                C     .656           401 V-8 engine
GM, Spirit                 C     .195
GM, Sprint                C     .1969          Chevrolet/Suzuki, 3 Cyl.
Honda, Prelude      S     .008-.010      2.0L engine
Honda, CRX            C     .017           1.5L engine 
Honda                     C     .030           Small cup
Honda                     C     .030           #K4SC16AG Cast Number
Honda                     C     .100-.104      
Honda                     C     .785           Long alignment pins
Honda                     C     .900            Short alignment pins
Honda, Accord       C     .615           1986
Hyundai, Excel       F     .000            Mitsubishi engine
Hyundai, Sonata     C     .157           1989 2.4 & 3.0L engines
Isuzu                        C     .010-.017      Trooper, Pup
Isuzu                        C     .151-.159      2.6L engine
Isuzu, Diesel           C     1.691-1.695    6BD1 & 6BDT engines
Mack Midliner,MIDR  F     1.260 Min.     Measure from crank/mount to disc
Mack Midliner,MIDS  C     1.500          Renault engine
Mazda                     S     .020           323, 1.6L engine
Mazda                     C     .062           RX2 Rotary engine
Mazda                     C     .310           B2000, 2.0L engine 
Mazda                     C     .640           1984 Rotary, 227 Cast number
Mazda, 2.2L, 1987   C     .785           Hyd. Clutch, Segmented wheel
Mazda, 2.0L             C     .805           Hyd. Clutch, .020 max/removal
Mercedes, 240D      C     .885
Navistar, 404/446    F     .750           New thickness
Navistar, 268D        S     .110           German Diesel engine
Navistar, 466D        F     1.430          
Navistar, 6.9L          F     1.410          Minimum thickness
Navistar 9.0L           F     1.585          Minimum thickness
Navistar 9.0L           F     .907           New thickness
Nissan                     F                     With groove
Nissan, Maxima      S     .003-.005      New thickness 1.010
Nissan, Maxima      F                     With groove, #425 Cast Number
Nissan,                    S     .003-.005      No groove
Nissan 1.6 & 2.0L    S     .006-.010      Sentra, Stanza
Nissan, B2000         C     .807 new       Max stock removel .020
Nissan, 240Z           S     .010           With groove
Peugeot                   S     .020           
Renault                    S     .014-.021      1.4L Alliance
Saab, 96                  C     .656
Subaru                     C     .830           Justy
Subaru                     C     .875
Subaru                     C     .905           4X4 Brat
Subaru                     C     .930
Suzuki                      C     .070
Suzuki                      C     .197           1.0L, 3 cyl
Toyota                     S     .018-.022      Large alignment pins
Toyota, 22RE          S     .018-.022      #627 Cast Number
Toyota                     C     .055           Small cup
Toyota                     C     .965-.970      Tercel, large cup
Toyota                     S     .040           Tercel, 3E engine
Toyota                     S     .015           3VZE engine
Toyota                     S     .020           Land Cruiser
Volvo                       C     .947           B230F engine
VW                           C     .945           Air cooled, 6 Volt
VW                           C     .913-.918      210MM Clutch
VW                           C     .830-.835      Rabbit,Golf,Scirocco
Vanagon                  C     .982           Water/Air cooled bus engine
VW                            C     .830           Air cooled engine
VW                            C     .885           Air cooled engine

                                  C = Cup, S = Step, F= Flat

Specifications listed for Step type flywheels refer to the height of the wear surface above the pressure plate mounting surface.  Specifications for Cup type flywheels refer to the height of the pressure plate mounting surface above the wear surface. 

                                                                        The AERA Technical Committee