Measuring Connecting Rod Bearing Clearance - Using J 43690/J 43690-100

J 43690  and J 43690-100  have been developed as a more accurate method to measure connecting rod bearing clearances. The instructions below provide an overview of tool set-up and usage. For more detailed information, refer to the tool instruction sheets as supplied by the tool manufacturer.

J 43690 

Fig 1: Identifying J 43690

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• J 43690-20 Swivel Base (1)
• J 43690-19 Dial Indicator (2)
• J 43690-2 Base (3)
• J 43690-5, -6 Handle (4)
• J 43690-10,-11 Foot (5)
• 280307 Screw (6)
• J 43690-1 Pivot Arm Assembly (7)
• J 43690-3, -7, -8 Screws (8)
• 280319 Screw (9)
• 280311 Screw (10)
• J 43690-17, -18 Adapter (11)
• 280310 Pin (12)

J 43690-100 

Fig 2: Identifying J 43690-100

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• J 43690-104 Spacer (1)
• J 43690-105 Retainer Plate (2)
• 505478 Bolt (3)
• 511341 Bolt (4)
• J 43690-106 Retainer Plate (5)
• J 43690-107 Cap (6)
• J 43690-102 Foot (7)
• J 43690-101 Pivot Arm Assembly (8)
• J 43690-103 Adapter (9)
• 505439 Adapter (10)

Important:  The crankshaft must be secure with no movement or rotation in order to obtain an accurate reading.

1. Rotate the crankshaft until the journal/connecting rod to be measured is in the 12 o'clock position.
2. Remove a bearing cap and bolts (1).
3. Remove the bearing half (2).
4. Insert a piece of paper card stock onto the crankshaft journal.
5. Install the bearing half (2) and cap and bolts (1). Refer to Fastener Tightening Specifications .
   Fig 3: Removing Bearing Cap And Bolts

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6. Install the following:
   1. 6.1. J 43690-2 (5)
   2. 6.2. J 43690-3 (4)
   3. 6.3. J 43690-101 (2)
   4. 6.4. 280310 (3)
   5. 6.5. J 43690-5 (1)
   Fig 4: Installing J 43690 Components

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7. Install the swivel base (1) and dial indicator (2).
   Fig 5: Installing Swivel Base And Dial Indicator

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8. Adjust per the manufacturers instructions and measure the connecting rod bearing clearance.

   A connecting rod with a clearance in excess of 0.076 mm (0.003 in) is considered excessive. Service components as required.