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Repair Of Worn Cam Bearing Housing Bores For Detroit Diesel 11.1l And 12.7l Diesel 60 Series Engines


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Engine Builders: The AERA Technical Committee offers the following information regarding the possible repair of worn cam bearing housing bores for Detroit Diesel 11.1L and 12.7L diesel 60 Series Engines. These engines use an overhead camshaft design with seven individual location precision bearing inserts. Over time, the bearing bores may become worn oversize or out-of-round, or an insert may even spin in its bore.

To repair a cylinder for re-use, DDC offers three different oversize outside diameter (OD) bearings. To use the bearings the cylinder head must be align bored to the larger oversize bore selected. Align boring this massive cylinder head requires supporting the cylinder head during the machining to prevent distortion (sag).


Before machining, assemble the numbered caps in their respective locations and torque to 75-86 FT/LBS. The standard housing bore is 2.7163-2.7178˝ (68.994-69.031mm) for all seven locations. The additional oversize bores are specified below in Chart 1.

Bearing Size

Part Number

Housing Bore Diameter




(68.994-69.031 mm)

.254 mm


(69.248-69.285 mm)

.508 mm



(69.502-69.539 mm)

.762 mm



Figure 1. Standard and oversize bearings are available to repair worn cam bearing
housing bores in Detroit Diesel 11.1L and 12.7L diesel, 60-Series engines.


Engine Builders: The AERA Technical Committee offers the following information on a revised fuel injector seal/ring on 1997-2002 Navistar DT466E & 530E engines. An improved single seal is released for use in the fuel injector middle groove position. This new seal replaces the existing cushion ring and seal combination as shown below in Figure 2.

The new middle groove single seal can be identified by its color of blue and black while the original seal has a white coating and the cushion ring is green and black. The new single seal replaces the previous ring and seal combination. The fuel injector assembly part number suffix has been advanced and the seal package part number changed to distinguish the new single seal.


Injector seals and rings are not serviced separately. The seal package contains all seals and rings needed to service one injector assembly (p/n 1823492C97). If one seal on a fuel injector needs to be replaced, the entire set (for that injector) must be replaced.

Each seal has been designed for a specific location on the injector, must be in the proper location and must be free of damage as well as foreign material. Improper installation of the seals could adversely affect engine performance.

Engine Builders: The AERA Technical Committee offers the following information regarding coolant loss on 1996-2002 Ford 4.6L VIN 6, 9, W & X engines. Varied amounts of coolant loss have been reported; on the above listed engines. In some instances no obvious external sign of the coolant has been seen.

In these instances, coolant loss may be traced to small cracks in the intake manifold coolant crossover. The coolant crossover is located below the first intake runner as shown in Figure 3.


Damaged intake manifolds should be replaced. Ford Motor Company offers eight different services consisting of new intake manifolds and all the necessary replacement items specific to individual Ford car or truck models.

Engine Builders: The AERA Technical Committee offers the following information from General Motors regarding a revised cylinder head torque on 2001-2002 3.1 & 3.4L engines. Vehicles with the 3.1L engine will have the Vin Code of J while the 3.4L engine will have the Vin Code of E.


To correctly install the cylinder heads on these engines, tighten the cylinder head bolts to 44 ft.lbs. (60 Nm) in the sequence shown in Figure 4. Using a torque angle meter, turn the bolts an additional 95



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