So you wanna be a mechanic, huh?

Here’s a head scratcher…
1999 GC 247k, original crank pulley, tensioner, belt. Tensioner showing subtle signs of spring/bearing wear. Small wobble at crank pulley. Time to replace with good components.
Ordered Gates Serpentine Kit (Tensioner/Belt) and Dorman Harmonic Ballancer off of Amazon.
Balancer came off straight and slow. Replaced front crank seal, cleaned and lubed area prior to pressing balancer on.
Used Long Reach Installer. Lubed collar inside and out and cranked her in as far as she’d go showing @ 1/4" of bare collar.
Tensioner installed at correct torque. Belt fit nicely.
Upon firing up my 4.7 I observed miniscule crank wobble. Belt riding slightly off tensioner pulley. Good throttle response.
Went thru usual checks on tensioner, e.g., remove and chk for clean mating area, correct torque at tensioner/
tension idler/idler pulleys, bearing sound/feel, pulley allignment, etc.
Realized after several checks and adjustments that by placing the spacer from old pulley on the new that it would smudge her over a hair.
Idea worked! My colleague, Kevin talked me into it. Went to take a spin to WM and noticed oil pressure running high. Stopped and popped hood. Balancer wobble scared the %#@! outta me. I knew Kevin’s idea was taking the easy way out! :yum:
Removed Tensioner. She wasn’t holding near enough tension. Replaced with Duralast. Belt in proper allignment. Crank pulley bolt holding at 130 fps. Felt good about this.
Fired and Kevin had me shut down immediately due to severe balancer wobble. Dorman Tech Support reluctantly felt balancer was defective. UPS picking up my Amazon return in the morning. New Dorman arriving Monday.
Is it worth a try to install old balancer and see how she spins? Could’ve been a counterfeit Dorman pulley. Looked pretty shabby out of the box. Any ideas, advice, blessings?

Sounds like the crankshaft nose is damaged which is quite common in cases like that. The crank is screwed and unfortunately so are you. The problem is the crank; not the balancer and this is not as rare a problem as you might think.

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