Remove Harmonic Balancer from GM 3800 Engines

Having a hard time removing the retainer bolt from the harmonic balancer to replace seal or crank position sensor? In many cases this bolt seems to be either glued in or welded. Needless to say, it is VERY tight. This article will guide you to do this job.

Steps

  1. Do the usual jacking and placing of car on jack stands procedure (safety first).
  2. Remove the serpentine belt, right front wheel and front splash guard. Observe a 15/16" hex in center of harmonic balancer (it's metric, but a 15/16" socket will fit).
  3. To keep the crankshaft from turning, fabricate a crankshaft retaining tool from whatever scraps at your disposal. This can be a piece of 1/4"X 3/4" flat iron stock with holes drilled and tapped for 5/16"X 1-1/2" bolts appropriately spaced to fit in holes in the harmonic balancer.
  4. Impact wrench (1/2" or preferably 3/4") only partly factor in here. Also needed is a good 18" pipe wrench and about a 24" box end wrench large enough to use as a pry bar over the handle of the pipe wrench.
  5. While an assistant below uses the impact wrench with a 15/16" deep impact socket, simultaneously from above apply reverse pressure on the socket with the pipe wrench and box end wrench for leverage. You must push hard until you hear a crack, which is the bolt breaking loose.
  6. Reload pipe wrench and go at it again repeatedly until the impact wrench can handle removal by itself.

Warnings

  • Make sure the fabricated crank retainer is propped against the frame and fits securely into the harmonic balancer. Slipping will result in mashed knuckles and much cursing.

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