52191 Mercruiser PLUG, EXPANSION - CAM

Note: Either Tooling (A) can be used. Use the Tooling that is most suitable.
Illustration 1 g06512670
Typical example
(1) Idler gear 2
(2) Balancer gear 1
(3) Idler gear 1
(4) Balancer gear 2Inspect the gears for wear or for damage. If the gears are worn or damaged, use new parts for replacement. Refer to Disassembly and Assembly for more information.Backlash for Balancer Gears
Backlash Between the Crankshaft Gear and the Balancer Idler Gear 1
Use Tooling (A) to rotate the crankshaft so that number one piston is at the top center position on the compression stroke. Refer to Systems Operation, Testing and Adjusting, Finding Top Center Position for No.1 Piston for the correct procedure.
Remove Tooling (B) from the camshaft.
Remove the flywheel. Refer to Disassembly and Assembly, Flywheel - Remove for the correct procedure.
Remove the crankshaft rear seal. Refer to Disassembly and Assembly, Crankshaft Rear Seal - Remove and Install for the correct procedure.
Mount Tooling (C) on a suitable flat surface to measure the backlash between the crankshaft gear and the balancer idler gear 1. Ensure that the point of the finger attachment is in contact with the balancer idler gear 1. The backlash measurement point is half way down the pitch circle diameter and along the relevant tooth.
Set the dial gauge indicator to zero. Gently rotate the balancer idler gear 1 backwards and forwards. Measure the backlash between the crankshaft gear and the balancer idler gear 1 in both directions. Refer to Specifications, "Gear Group (Rear) - Engines with a Balancer" for the backlash measurement.Note: Apply a sufficient force to be able to rotate the balancer idler gear 1, but not enough force to rotate the crankshaft.Backlash Between the Balancer Idler Gear 1 and the Balancer Idler Gear 2
Remove the engine oil pan. Refer to Disassembly and Assembly, Engine Oil Pan - Remove and Install - Cast Iron Oil Pan With Balancer for the correct procedure.
Use a suitable tool to clamp balancer idler gear 2 in position. Ensure that balancer idler gear 2 is not damaged when the operation is performed.
Mount Tooling (C) on a suitable flat surface to measure the backlash between the balancer idler gear 1 and the balancer idler gear 2. Ensure that the finger attachment is vertical. Ensure that the point of the finger attachment is in contact with the balancer idler gear 1. The backlash measurement point is half way down the pitch circle diameter and along the relevant tooth.
Ensure that the other gears that mesh with balancer idler gear 1 can rotate freely. The other gears should not restrict the movement of the gear that is being measured.
Set the dial gauge indicator to zero. Gently rotate the balancer idler gear 1 backwards and forwards. Measure the backlash between the balancer idler gear 1 and the balancer idler gear 2. Refer to Specifications, "Gear Group (Rear) - Engines with a Balancer" for the backlash measurement.Note: Apply a sufficient force to be able to rotate the balancer idler gear 1, but not enough force to damage the locking tool.Backlash Between the Balancer Idler Gear 1 and the Balancer Gear 2
Use a suitable tool to clamp balancer gear 2 in position. Ensure that balancer gear 2 is not damaged when the operation is performed.
Mount Tooling (C) on a suitable flat surface to measure the backlash between the balancer idler gear 1 and the balancer gear 2. Ensure that the finger attachment is vertical. Ensure that the point of the finger attachment is in contact with the balancer idler gear 1. The backlash measurement point is half way down the pitch circle diameter and along the relevant tooth.
Ensure that the other gears that mesh with balancer idler gear 1 can rotate freely. The other gears should not restrict the movement of the gear that is being measured.
Set the dial gauge indicator to zero. Gently rotate the balancer idler gear 1 backwards and forwards. Measure the backlash between the balancer idler gear 1 and the balancer gear 2. Refer to Specifications, "Gear Group (Rear) - Engines with a Balancer" for the backlash measurement.Note: Apply a sufficient force to be able to rotate the balancer idler gear 1, but not enough force to damage the locking tool.Backlash Between the Balancer Idler Gear 2 and the Balancer Gear 1
Use a suitable tool to clamp balancer gear 1 in position. Ensure that balancer gear 1 is not damaged when the operation is performed.
Mount Tooling (C) on a suitable flat surface to measure the backlash between the balancer idler gear 2 and the balancer gear 1. Ensure that the finger attachment is vertical. Ensure that the point of the finger attachment is in contact with the balancer idler gear 2. The backlash measurement point is half way down the pitch circle diameter and along the relevant tooth.
Ensure that the other gears that mesh with balancer idler gear 2 can rotate freely. The other gears should not restrict the movement of the gear that is being measured.
Set the dial gauge indicator to zero. Gently rotate the balancer idler gear 2 backwards and forwards. Measure the backlash between the balancer idler gear 2 and the balancer gear 1. Refer to Specifications, "Gear Group (Rear) - Engines with a Balancer" for the backlash measurement.Note: Apply a sufficient force to be able to rotate the balancer idler gear 2, but not enough force to damage the locking tool.
Check the end float for the balancer gears. Refer to "End Float for Balancer Gears" for the correct procedure.End Float for Balancer Gears
If necessary, use Tooling (A) to rotate the crankshaft so that number one piston is at the top center position on the compression stroke. Refer to Systems Operation, Testing and Adjusting, Finding Top Center Position for No.1 Piston for the