For drawing in the timing chain.

Retains timing chain with camshaft sprockets in proper timing position.

Makes it possible to position the camshafts in the installed position.

Makes it possible to slacken and tighten the bolts attaching the camshaft gear.

To install the plug into the timing case cover(access to chain tensioner)

For unloading the timing chain tensioning device.

Release the timing chain.

To do this,in the timing case and push back the tensioning rail.