Kent-Moore J-43690-A Rod Bearing Checking Tool
For General Motors. 5.0, 5.7, 3.0, 3.1, 3.4, 4.3, 7.4, 8.1L, Engines J-43690 is used to diagnose rod bearing clearance on customer complaints of hot & cold engine knock noise. GM has determined that Plasti-Guage is not a reliable method to use for checking rod bearing clearance. J-43690 applies to only the non-deep skirted engines listed above. Adapters for deep skirted engines (2.2, 3.5, 3.8, 4.0, 4.6, 5.3, 6.0L) will be required. One of the causes of engine knock noise is excessive connecting rod bearing clearance. Typically, this noise occurs at initial start-up, and may be audible up to 1, 500 or 1, 800 rpm. Rod bearing knock typically diminishes or goes away at normal temperature. The traditional method of checking connecting rod bearing clearance involves disassembling and cleaning the rod bearing, inserting a length of Plasti-gauge and torquing the fasteners to specification, then disassembling again and measuring the width of the crushed Plasti-gauge. This method is time consuming and labor intensive and it disturbs the very clearance you are attempting to measure. Use J-43690 to measure connecting rod bearing clearance without disassembly. Following the procedure in the instructions included with the tool or the GM published service procedure, clamp a piece of paper stock in one of the intermediate crankshaft main bearing to keep it from turning. Then attach the pivot arm of the tool to the rod, and bolt the base to the oil pan rail. With the kit's test Indicator on the bearing cap, use the tool to move the connecting rod up and down on the bearing journal and record the measurement. If clearance is OK, you'll leave the connecting rod bearing surfaces undisturbedEmail
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