| The following technical bulletins were published by AERA. |
| | EXCESSIVE OIL CONSUMPTION | Excessive Oil Consumption
on 1978-89 Chrysler Jet Valve Engines
AERA members have reported excessive oil consumption and spark plug fouling complaints on 1978-89 Chrysler jet valve engines. These engines are manufactured for Chrysler Corporation by Mitsubishi Motor Corporation of Japan.
There are several possibilities for allowing oil to pass into the combustion chamber. They are oil leaking past the valve stem seal or the jet valve body O-ring, or a worn jet valve body or valve stem. Since oil can travel among the various air passages in the cylinder head casting, it is important to inspect all jet valves not just the cylinder that is indicated by a fouled spark plug.
Remove the jet valve assembly as indicated in the appropriate service manual and inspect the O-ring for nicks, cuts, tears or deformation. Likewise, a brittle O-ring is not capable of sealing out lubricating oil. The O-ring, Chrysler part #MD009786, should be replaced whenever the jet valve assembly is removed from the cylinder head.
Disassemble the jet valve assembly and inspect the valve stem seal for damage or deformation. Chrysler recommends replacement of the complete assembly if the valve body or valve stem are worn. Use Chrysler part #MD009440.
Any oil residue or carbon must be removed from the jet valve passages before assembly. See the appropriate OE or aftermarket manual for further information and torque values.
The AERA Technical Committee | | REAR MAIN SEAL LEAKS ON 1986 & LATER ENGINES | Rear Main Crankshaft Seal Leaks On
1986 And Later Chrysler 5.9L (360 CID) Engines
The rear main crankshaft seal bore on some Chrysler 5.9L (360 CID) engines built after 1986 may not be concentric with the centerline of the main bearing bore.
This causes irregular contact between the rear main seal and the crankshaft, leading to oil leaks at the rear of the engine. Depending on position, the seal may barely make contact with the crankshaft or may be flattened because of the closeness of the crankshaft seal surface.
Chrysler Corporation has released a Viton rear seal, Part #4483456, replacing Part #4240101, that should be used in this situation. The number on the seal itself is 501473.
At the present time aftermarket gasket manufacturers are packing the former Polyacrylate rear main seal with their gasket sets, which should work well in most applications. However, install the Viton seal whenever a cylinder block with a non-concentric rear main crankshaft seal housing bore is used.
The AERA Technical Committee | | CYLINDER HEAD/VALVE TRAIN CHANGES ON 1985-91 ENGINES | Cylinder Head/Valve Train Changes
Chrysler 5.2 & 5.9L (318 & 360 CID) 1985-1991 Engines
Beginning with the 1985 model year, Chrysler manufactured the 5.2L (318 CID) engines with roller lifters & camshaft. The 1989 model year brought the same design to 5.9L (360 CID) engines. Upon doing so, the size of the push rod socket in the lifter increased to a diameter of .650 (16.51mm). Older non-roller heads have a push rod socket diameter of .500 (12.7mm).
Using older, non-roller cylinder heads on the roller lifter engines can result in push rod to cylinder head contact in that area where the push rod passes through the cylinder head. The 5.2L (318 CID) roller cam cylinder heads are easily identified by the kidney shaped or high swirl port combustion chamber.
Identification of the 5.9L (360 CID) head is more difficult, as both heads share the same 70cc combustion chamber.
The roller cam engine also uses a shorter push rod than the non roller engine. The length of it measures 6.794-6.814 (172.567-173.076mm). Non roller engines use a push rod with a length of 7.505-7.525 (190.627-191.135mm).
In the middle of the 1990 model production year, the push rod was changed from solid to hollow. The hollow push rod provides positive oil flow to the rocker arm socket when used with the later style rocker. The later rocker does not have an oil hole in the push rod socket, whereas all earlier rockers had an oil hole opening in the socket.
Be sure to use the appropriate rocker arm and push rod combination when assembling roller camshaft engines. The solid push rod uses a rocker arm with an oil hole in the push rod socket, while the hollow push rod's rocker arm should not have an oil hole opening in the push rod socket. If the hollow push rod
is matched with the rocker that also has an oil hole in the push rod socket, excess oil will be transported up the push rod, through the rocker's oil hole and into the rocker cover cavity. Excessive oil in this area may lead to engine oil consumption if the valve stem seals are overcome.
Along with push rod and rocker changes, the roller lifters were also modified. The lifters that are used with hollow push rods now have an oil feed hole in the push rod socket. Again, use the lifter with the oil hole on engines with hollow push rods.
Extreme caution must be taken when changing cylinder heads and valve train components on Chrysler built 5.2 & 5.9L (318 & 360 CID) engines. Failure to do so, may result in severe engine damage.
For additional information see AERA bulletins: TB 493 & 712
The AERA Technical Committee | | CAMSHAFT HOUSING CAUTION | Camshaft Housing Bore Align Bore Caution On
Chrysler 3.0L OHC Engines
It is common practice to reclaim the camshaft bearing surfaces on overhead camshaft engine cylinder heads when the camshaft has seized in the cylinder head. Usually the cam bearing caps are cut at the parting face and then the housing bore is align bored.
In the case of the Chrysler 3.0L engine this could lead to trouble, especially when more than .015 of material is cut off the cam bearing caps. As shown in the illustration, the rocker arm shafts and cam bearing caps form an integral assembly. Therefore, removing material from the cam bearing caps brings the rocker arm shafts closer to the valves.
Since valve lash is controlled by small lash adjusters that are located in the rocker arms, there is not very much room to play with before valve geometry is seriously affected. The result is valves that remain open even if the installed valve stem height of 1.635-1.650 is maintained.
It is best to remove as little material as possible from the cam bearing caps or if this is not feasible, reclaim the bearing surfaces through welding. Alternately, it is possible to fit the cylinder head for aftermarket cam bearing inserts.
The AERA Technical Committee | | OIL PUMP FAILURES | Oil Pump And Distributor Shaft Failures On
All Chrysler Equipped 5.2L (318 CID) Engines
Oil pump or distributor drive shaft failure on Chrysler 5.2L (318 CIM) engines may be caused by the lack of flatness or squareness of the oil pump mounting surface on the rear main bearing cap. Check to determine of there is a lack of uniformity in the machining marks on the surface indicating a faulty final
machining operation (Fig. 1). Also determine if there appears to be an interference of the drive shaft in the pump shaft during assembly.
The squareness of this area can be checked by placing a straight edge across the pump mounting surface and measuring to the cylinder block oil pan surface at two points. If the difference in distance from the straight edge to the block is more than .060 in a 6 span, the cap is excessively out of square, and the
cap should be remachined.
This condition should not be corrected with a file or other hand methods. Set up the cap in a mill by locating on the cylinder block face of the cap and machine the oil pump mounting surface to the 2.43 dimension shown in Fig. 2. Extend the threads for the oil pump mounting screws as far as possible into the present
holes in the cap with a 3/8-16 bottoming tap.
Make a spacer of 3/16 thick soft aluminum as per Fig. 3.
After the cap is reinstalled on the cylinder block, assemble the pump to the cap with the 3/16 spacer between the pump and the cap. Use 1-1/2 long 3/8-16 screws to attach the pump in place of the original 1-1/4 screws.
The AERA Technical Committee | | INSTALLING CUP TYPE CORE PLUGS BY CHRYSLER | Procedure For Installing Cup Type Engine Core Hole Plugs
Recommended By Chrysler Corp.
Chrysler Corporation recommended the following procedure to
eliminate the possibility of coolant leaks around the outside of
the core hole cup plugs:
1. Thoroughly clean the inside of the cup plug in the
cylinder head or block. Remove all traces of the old
sealer.
2. Be sure that replacement plugs are clean and free of
dirt, oil or grease.
3. Lightly coat the inside of the plug with Loctite or
equivalent.
4. Drive the replacement plug into the plug hole with a
proper driver so that the plug hole is at least .020
past the bottom of the hole chamfer.
5. If the recommended sealer is used, coolant may be
installed immediately and the engine may be placed in
immediate service.
CAUTION: Some Chrysler engines are produced with one or more
oversize core hole plugs or cam bearing plugs. These
oversize plugs are cadmium plated and must be replaced
with plugs of the correct size.
The AERA Technical Committee
January 1976 - SPB 31
##END## | | CAM BEARING ALTERNATIVE CHRYSLER 3.3L & 3.8L | Cam Bearing Alternative For
1991-2001 Chrysler 3.3 & 3.8L VIN G, J, T, U, R & L Engines
The AERA Technical Committee offers the following information regarding a cam-bearing alternative for 1991-2001 Chrysler 3.3 & 3.8L VIN G, J, T, U, R & L engines. This alternative cam bearing set may be used anytime they are being replaced in an engine.
Previously, AERA published Technical Bulletin TB-1254 concerning a lack of oil supply to either side rocker shaft for these engines. The root cause of that condition was either an out of place cam bearing or a restriction in the oil supply around the camshaft. To make a transfer through the lower portion of the block to the upper portion of the block engine oil was routed through a groove in the cam. On occasion that transfer of oil was impaired and an insufficient amount of oil reached the rocker shafts.
AERA is aware of at least two engine parts suppliers who offer camshaft bearings for the intermediate locations with a groove machined around the outside of the bearing. This groove will help eliminate alignment concerns technicians may have while installing the bearings at those locations. This additional groove assures uninterrupted oil supply to the rocker shaft assemblies around the backside of the bearing. This revised bearing design has been performing well in the field without subsequent rocker shaft concerns. Consult your engine parts supplier for availability of this revised bearing set.
The AERA Technical Committee | | EXTERNAL COOLANT LEAKS ON 1987-89 ENGINES | External Coolant Leaks On
1987-89 Chrysler 3.0L Engines
Chrysler reports that some 1987-89 3.0L engines may experience engine coolant loss from leaks at the cylinder head gasket area.
If such a leak is suspected, attach a radiator pressure tester to the cooling system and apply 15 psi of pressure. Inspect the head gasket joint of each bank for signs of seeping coolant. Any leaks should be cured by replacing the cylinder head gasket. Chrysler recommends replacing both head gaskets even if only one bank is leaking.
Chrysler has updated the cylinder head gasket, Part #MD143540, replacing the former gasket Part #MD111805, to prevent such leaks. The new gasket features an .080 wide bead of print-o-seal around the water ports. The former gasket used a .060 wide bead.
The replacement gasket designed by aftermarket gasket manufacturers has always been fitted with an .080 wide bead of print-o-seal.
The AERA Technical Committee | | LOW ENGINE PERFORMANCE ON 4.7L VIN N ENGINES | Low Engine Performance On
2000 Chrysler 4.7L VIN N Engines
The AERA Technical Committee offers the following information regarding low engine performance on 2000 Chrysler 4.7L Vin N engines. Customers may complain of a lower than expected engine performance. The loss or intermittent loss of the camshaft position sensor (CMP) signal could cause this.
The loss of the CMP signal may be the result of the CMP coming in contact with the tone wheel. If this occurs, the internal electronic circuitry of the CMP may become damaged. When this happens, there is a chance that the Malfunction Indicator Lamp (MIL) may become illuminated.
Most of these engines were inspected and repaired at the manufacturing facility. Some engines may need to be repaired. If the engine is in need of repair, there is a select fit shim that needs to be installed between the CMP and the cylinder head pad, around the CMP sensor attaching bolt as shown in Figure 1. The shims come in four different thickness depending on the amount of air gap that needs to be shimmed. The four sizes are .010, .020, .031 and .047.
The shim may also have been glued in place to either the cylinder head or the mounting tang on the camshaft position sensor. If a technician is making repairs, they may overlook or lose the previously installed shim. This may cause the camshaft position sensor to contact the tone wheel when the CMP sensor is reinstalled or replaced.
Part Number Part Description Qty
05019089AA Kit, CMP sensor shim (.010, .020, .031, .047) 1
53020878 Gasket Engine Cylinder Head Cover Right Side 1
56028133AD Sensor, Camshaft 1
The AERA Technical Committe |
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