Author Topic: Harmonic balancer help  (Read 107 times)

Zach

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Harmonic balancer help
« on: May 07, 2025, 11:29:34 AM »
Howdy, my harmonic balancer wobble has gotten significantly worse I can easily see it at idle, noticed a very marginal wobble last year. I keep the rpm’s under 4k on pulls. Previous owner put in a crank shaft 20 years ago so I have no idea if it was all installed properly. Can anyone tell me the proper torque for the bolt and or any other steps I should take, will also take suggestions on a new quality balancer I’m 99 percent sure it’s the original one. Also any tips on how to lock the engine to torque the bolt. I have a video of the wobble if you are curious but I figured a wobble is a wobble so it shouldn’t matter. The max performance py forums that all my googling brings me too seems to have a database error on my end and I can’t look at any old forum posts and couldn’t find any on this forum easily.

Thanks.
1977 #s W72 400 4 Speed Trans Am
1971 351c 4 Speed Mustang Mach 1

71455formula

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Re: Harmonic balancer help
« Reply #1 on: May 10, 2025, 01:31:44 PM »
On a Pontiac engine the balancer only goes on one way. There is a woodruff key the puts it in the right position. The bolt is torqued to 160 lb-ft. Here is the balancer i use. It's a great upgrade over stock. Here is the balancer and a woodruff key.

https://butlerperformance.com/i-24453461-powerbond-pontiac-1968-up-except-301-performance-street-4-bolt-harmonic-balancers-dampers-w-timing-marks-non-sfi-pbo-pb1056st.html?ref=category:1234723

https://butlerperformance.com/i-30861834-crank-key-standard-each-pio-pk-126.html?ref=search:http%3A%2F%2Fbutlerperformance.com%2Fsearch.html%3Fq%3Dkey

While the balancer is out; its a good time to look at the front main seal to see if it's still good or needs to be replaced. Make sure to put a little oil on the balancer to help with front main seal to slip over the balancer.
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tinpusher

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Re: Harmonic balancer help
« Reply #2 on: May 10, 2025, 02:08:24 PM »
X2

tajoe

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Re: Harmonic balancer help
« Reply #3 on: May 11, 2025, 08:31:19 PM »
If you can visually see the balancer "wobbling", you probably have bigger problems then a loose bolt. Doesn't matter if it's 50 in/lbs, or 50 ft/lbs, if it's that far gone, it needs replacing, "before" it comes apart. If your belt pullys aren't following the outter shell of the balancer, then maybe the rubber has deteriorated so bad, it's gunna go...maybe any day. Hoping for the best.
"You can sell an old man a young mans car,
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Zach

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Re: Harmonic balancer help
« Reply #4 on: May 11, 2025, 09:38:31 PM »
If you can visually see the balancer "wobbling", you probably have bigger problems then a loose bolt. Doesn't matter if it's 50 in/lbs, or 50 ft/lbs, if it's that far gone, it needs replacing, "before" it comes apart. If your belt pullys aren't following the outter shell of the balancer, then maybe the rubber has deteriorated so bad, it's gunna go...maybe any day. Hoping for the best.

Yeah that is sort of what I was thinking, I have it parked currently. Ordered a powerbond balancer a few days ago and a new bolt. I really just need this engine to survive another year or so for the 71 to be done then this engine will come out and get a full refresh.
1977 #s W72 400 4 Speed Trans Am
1971 351c 4 Speed Mustang Mach 1

Re: Harmonic balancer help
« Reply #4 on: May 11, 2025, 09:38:31 PM »

FormTA

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Re: Harmonic balancer help
« Reply #5 on: May 12, 2025, 03:58:09 AM »
Let us know how it goes
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Re: Harmonic balancer help
« Reply #5 on: May 12, 2025, 03:58:09 AM »
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