How much cam end play is acceptable when working on a Nissan Quest cylinder head?
The AERA Technical Committee explains that the following information regarding camshaft end play for 1996-2004 Nissan 3.3L engines (Pathfinders and Quests) should be referenced whenever camshaft or cylinder head service is performed.
Install the camshaft and locate plate in the cylinder head and torque the plate bolt to 57-65 ft.lbs. (78-88 Nm). Then, measure the camshaft end play as shown in Figure 1. Camshaft end play should be .0012-.0024″ (.03-.06 mm).
There are three additional thickness plates available for service and each is marked to indicate its size. If it is out of the specified range, determine if an available different thickness plate will achieve the proper camshaft end play. Refer to the illustration in Figure 2 to determine if a different plate will provide the correct amount of end play.
As an example: When camshaft end play is .0031″ (.08 mm) with camshaft locate plate 1, replace camshaft locate plate 1 with camshaft locate plate 4 to set the end play at .0016″ (.04 mm).
If the correct end play cannot be established, either camshaft or cylinder head replacement may be required.
Can you explain the alternative cam bearing repair for Cummins 5.9L B-series diesels?
There have been several different bearings with different dimensions used for these engines. AERA’s Technical Committee says an alternative cam bearing bore repair for 1985-99 Cummins 5.9L B Series diesel engines requires a single repair operation for many engine blocks, allowing them to be put back into service.
Cummins supplies multiple part numbers for the different locations and the front bearing is slightly wider than the other 2-7 locations. The Cummins p/n 3904369 which is listed as an oversize repair bushing for the front is actually the same as the late model standard size front cam bearing. Refer to Figure 3 for help in selecting the bearings required.
To install these oversize bearings, first determine a .0020-.0025″ interference fit before align boring the camshaft housing bore.
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