| 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## |
| REVISED TIMING COMPONENTS |
Revised Timing Components On
1988 Nissan Z24I Engines
Nissan has revised the timing components used in 1988 and later Z24I engines. The actual production change was instituted in January of 1988.
The chain assembly was updated from a single roller to a double roller type. This update requires a new crankshaft and camshaft sprocket as well as the new double roller chain. The tensioner assembly and chain guides have not been changed. Engines manufactured prior to January 1988 may be serviced with the new components as long as all three pieces are used.
The AERA Technical Committee |
| INJECTOR NOZZEL SERVICE |
Injector Nozzle Service On
Nissan SD Series Engines
Nissan has revised the lower fuel injector gasket on their SD series diesel engines.
This engine was introduced in 1981 as the SD-22 with a displacement of 2.2L. In 1984 the cylinder bore diameter was increased to bring engine displacement to 2.5L. This engine, the SD-25, was last used as part of the 1986 model year.
Nissan recommends replacement of both upper and lower fuel injector gaskets whenever the injector assembly is removed from the cylinder head. Be sure to position the lower gasket with the convex edge toward the combustion chamber (see Illustration).
The AERA Technical Committee |
| COOLANT IN THE ENGINE OIL |
Coolant In The Engine Oil In
1989-99 Nissan 2.4L KA24 Engines
AERA members have reported engine coolant in the engine oil supply in 1989-99 Nissan 2.4L KA24 engines. Vehicle owners have expressed engine-overheating complaints and loss of engine coolant. The source of this coolant loss has not been the cylinder head, which is most often first suspected. Removal of the cylinder head may not be necessary if the information in this bulletin is first considered.
These engines use a timing chain to rotate the single or dual camshaft design used. If that chain is allowed to run loose, it may contact the front cover and wear a hole into the aluminum cover allowing coolant to enter the crankcase. To determine if this condition is present, some technicians have detected the area of leakage by attempting to pressurize the cooling system. Before any pressure builds up, an audible hissing noise has been noticed and verified with a stethoscope at the engine?s front cover.
For more information on this engine?s timing chain tensioner, see TB-1652
The AERA Technical Committee |
| ENGINE COOLANT LEAKS ON 2000-2002 NISSAN 3.3L ENGINES |
Engine Coolant Leaks On
2000-02 Nissan 3.3 VG33E Engines
The AERA Technical Committee offers the following information regarding an engine coolant leak on 2000-02 3.3 VG33E engines. Customers may complain of engine coolant under the vehicle if sitting for a period of time or the smell of coolant when the engine is warm.
A leak between the intake manifold and the water outlet housing as shown below in Figure 1 may be causing this condition. Visually inspecting this area could verify that this is the source of the leak.
To cure this problem, Nissan offers a revised fiber gasket, Part #11062-9Z000, to be installed between the water outlet and the intake manifold. When changing this gasket, make sure that you have drained the coolant just below the level of the water outlet. This will keep coolant from spilling when removing the housing.
Clean the sealing surface of the water outlet housing and the intake manifold to get rid of any old sealer that may be present. Install the two mounting bolts through the outlet housing and then slide the fiber gasket over the bolts until it is flush with the sealing surface of the housing.
Once the housing is installed onto the intake manifold, tighten the mounting bolts to a torque of 12-15 ft/lbs. Refill the cooling system and run the vehicle to verify that there are no further coolant leaks.
The AERA Technical Committee |
| SEIZED CAMSHAFTS |
Seized Camshafts On
Nissan SOHC VG30 3.0L Engines
AERA has received reports of sudden camshaft seizures on Nissan SOHC VG30 3.0L engines. This seizure is uncommon because the cause of the failure is a broken cylinder head bolt. The head of the bolt breaks off and then becomes lodged under one of the cam lobes, resulting in the timing belt either breaking or stripping.
If this type of failure occurs, removal of valve covers will reveal that the bolt head is lodged underneath the camshaft. Further engine disassembly is now necessary as this is a non-freewheeling engine. Bent valves can be encountered on both cylinder banks, even if only one camshaft as seized.
For additional information see AERA Technical Bulletin: TB 601 &
TB 653
The AERA Technical Committee |
| TIMING CHAIN GUIDE BREAKAGE |
Timing Chain Guide Breakage On
1989-95 Nissan 1.6L GA16 Engines
AERA members have reported occasional timing chain guide breakage on
1989-95 Nissan 1.6L GA16 engines. The broken guide was usually discovered after complaints of poor performance or noise in the front of the engine. This condition may apply to both SOHC and DOHC engines.
The cause of this breakage may be due to constant inherent engine vibrations that caused the guide to fracture. To reduce the possibility of this reoccurring, Nissan has a revised chain tension guide and hold down bolt. The tensioner guide is available under Part #13085-77A04 for SOHC and Part #13085-0M300 for the DOHC engine. The hold down bolts are available under Part #08120-8161E or #08129-81628.
The revised timing chain guide and bolt should be installed whenever the engine is rebuilt or the timing chain replaced.
The AERA Technical Committee |
| CRANKSHAFT BREAKAGE ON 93-95 3.0L ENGINE |
Crankshaft Breakage On
1993-95 Nissan 3.0L Engines
AERA members have reported instances of crankshaft breakage on 1993-
95 Nissan 3.0L engines. This breakage usually occurs right in front of the front main bearing journal shortly after accessory belt adjustment or installation. The cause of this breakage has been determined to be overtightening of the accessory drive belts.
This engine application uses four belts that drive off the front of the crankshaft and slightly overtightening of any belt is cause for possible component failure. Nissan Motor Company issued a service bulletin (NTB95018) stating a possible accessory failure may result if a belt is overtightened. That bulletin did not however, mention crankshaft breakage.
To prevent possible crankshaft breakage and accessory failures, follow the chart listed below to correctly install the accessory belts on Nissan 3.0L engines. Note that a downward force of 22 pounds must be applied on the individual belt that is being adjusted and values for new and used belts are different.
The AERA Technical Committee |
| TIMING CHAIN GUIDE ELIMINATION |
Timing Chain Guide Elimination On
1991-93 1.6L DOHC Nissan Engines
The AERA Technical Committee has received information concerning the elimination of two timing chain guides on 1991-93 1.6L DOHC engines. Beginning with engines produced in March 1993, the top and left side timing chain guides were eliminated.
All replacement cylinder heads Part #11040-57Y01, will not have the drilled holes to attach the chain guides. Those guides are not necessary and may cause an undesirable rattling noise when the timing chain contacts the guide. To prevent a possible noise complaint, Nissan suggests removing the two guides shown in the illustrations below anytime cylinder head repair is done.
The AERA Technical Committee |
