T.s.b On Vg30e W-seires Changes

[s12god]

found a t.s.b. on vg30e w seires changes and why they made the changes in the late 80's. i thought it was good info so here it is.



REVISED CYL HEAD & BLOCK ON 1987-UP ENGINES
               Revised Cylinder Head & Block On
              1987-Up Nissan 3.0L (VG30) Engines


Beginning with April, 1987 production, the cylinder heads and
block have been changed on Nissan 3.0L (VG30) engines.
Improvements were made to increase power output and decrease
noise levels of the engine.

Revised production engines can be identified by an engine serial
number that ends in W, such as XXXXXX W.  Former engine serial
numbers end in either A or B.  However, factory service
cylinder blocks will not carry the W identification even though
they feature the improvements listed below.  A visual check is
necessary for proper identification.

Six new water galleries were added to the cylinder block (Figure
1) and the cylinder heads (Figure 2).  This change required a
modification of the cylinder head gasket, where the original 6
water holes were downsized and 3 new holes added on the exhaust
side of the gasket (Figure 3).  The revised cylinder head gasket
can also be identified by its differing identification tab.
Figure 4 best illustrates the former and revised head gaskets.

Additional changes were made throughout the engine.  The pistons
now use full floating, larger diameter wrist pins.  The small end
bore of the connecting rod was increased to accept the larger
wrist pin.  The revised rod is also heavier than the former part.
Again, components are identified by a W stamp.

Nissan advises against the use of former parts when servicing
vehicles with engines manufactured as of April 1987.  Refer to
the chart to determine the proper component combination when
servicing engines manufactured prior to April 1987 (Figure 5).

For additional information see AERA Technical Bulletins: TB 601,
653 & 752


                                    The AERA Technical Committee


     Cylinder   Head     Cylinder   Short   Acceptable
       Head    Gasket      Block    Block   Combination

      Revised  Former     Former     N/A        Yes
      Former   Former     Revised    N/A        Yes
      Former   Former     Former     N/A        Yes
      Revised  Revised    Revised    N/A        Yes
      Revised  Former     Revised    N/A        Yes
      Revised  Revised    Former     N/A        No
      Former   Revised    Revised    N/A        No
      Former   Revised    Former     N/A        No
      Former   Former       N/A    Revised      Yes
      Revised  Revised      N/A    Revised      Yes
      Revised  Former       N/A    Revised      Yes
      Former   Revised      N/A    Revised      No




April 1991 - TB 761

##END##

REVISED CRANKSHAFT
                     Revised Crankshaft On
                  1984-87 Nissan VG30 Engines


Nissan has revised the snout of the crankshaft and related
service parts for VG30 engines manufactured after April 1987.
Since only the revised crankshaft is being serviced by Nissan,
should it become necessary to use this crankshaft in 1984-1987
engines, several associated parts also need to be changed.
Engines manufactured prior to April 1987 carry a serial number
that ends in either 'A' or 'B'.


Component                Prior to            As of
Description              April 1987          April 1987


Crankshaft               12201-02P80 1       12201-02P81 2
Bolt Spacer              Not Required        12308-V5321
Crank Pulley Bolt Washer 12308-V5000 3       12308-77A00
                        12308-V5001 3
                        12308-V5010 3
Crank Pulley Bolt        12309-V5000         12309-16V00


1    Does not include crankshaft pulley bolt washer or
    crankshaft pulley bolt.
2    Includes crankshaft bolt spacer, crankshaft pulley bolt and
    crankshaft pulley bolt washer.
3    Complete application information available on parts
microfiche


The front pulley assembly is the same for either crankshaft.


                                    The AERA Technical Committee


March 1991 - TB 752

##END##

[MachZ]

http://www.machzracing.com/various/87%20Engine%20changes.rtf

[Xano]

This is good info, it will be going into the FAQ/HowTo section.