Info - Essential Tool J 43690 - Rod Bearing Clearance Checking Tool

A new service tool J 43690 and the supporting service procedure have been developed to more accurately measure connecting rod bearing clearances. Engines with excessive connecting rod bearing clearances may exhibit a cold knock/bearing rattle type noise (refer to Corporate Bulletin Number 99-06-01-003). Typically, this noise occurs at initial start-up and may be audible up to 1,500-1,800 RPM. The rod bearing knock typically diminishes or goes away at normal operating temperature. Tool J 43690 permits measurement of connecting rod bearing clearances without removing the connecting rod bolts, bearing cap, and bearings. The selective fitting of the connecting rod bearings is necessary in order to obtain close tolerances. For this reason, standard and undersized bearings are available. While the micrometer method of measuring for bearing clearances is acceptable, the use of J 43690 is the preferred method. The use of plastic gauging material will result in unreliable measurements and is not to be used.

Follow the tool instructions included with the tool or the revised electronic service information.