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Engine New harmonic balancer wobbles

  • Thread starter Thread starter keel
  • Start date Start date Jul 6, 2021

keel

Active Member
Aug 23, 2020
205
69
38
Seattle, Wa
Jul 6, 2021
#1
  • Jul 6, 2021
  • #1
Just installed a new OEM harmonic balancer on my 5.0. Is it normal for it to wobble still? Or could the part be damaged or my crank be damaged? I did not use a harmonic balancer installation tool but rather just used the crank bolt to tighten down the balancer, and I'm thinking it could be related to that but it seems that many people have no issues doing it that way.
 

Hoytster

I don't dare do that to my Knob
20+ Year Stangneter
Dec 30, 2002
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Cornwall, PA
Jul 7, 2021
#2
  • Jul 7, 2021
  • #2
Are you sure the harmonic balancer is wobbling and it isn't just the pulley? The balancer should not wobble if it's new, installed correctly, and the crank snout isn't bent. Technically you should use a installer tool to install the damper, but I've used the bolt many times with no problems. I usually use moly lube on the bolt threads and a lubed junk washer under the bolt head to drive the balancer in, then take it back out and put the permanent washer on and torque it down. I also heat the balancer in boiling water right before installation so it goes on little easier.

Are you sure the balancer is fully seated? What did you torque the balancer bolt to?
 

keel

Active Member
Aug 23, 2020
205
69
38
Seattle, Wa
Jul 7, 2021
#3
  • Jul 7, 2021
  • #3
I torqued it to 110 ft/lb.
 

Hoytster

I don't dare do that to my Knob
20+ Year Stangneter
Dec 30, 2002
1,069
700
164
Cornwall, PA
Jul 9, 2021
#4
  • Jul 9, 2021
  • #4
That should be good for a stock bolt (90 ft/lb is spec). I'd check everything closer to see if it's the balancer or your pulley. If it's the balancer, I would check runout on the bottom half (Hub) of the balancer to narrow it down to installation or the crank being bent, or something wrong with how they bonded the balancer (bottom half would measure correctly, the top half (outer mass) would have runout.
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,016
1,613
194
NJ
Jul 10, 2021
#5
  • Jul 10, 2021
  • #5
I think the first question has to be, why did you change it? Did the old one go bad and shake the hell out of the car?
Also, are you sure it's wobbling and not just an optical illusion?
 

keel

Active Member
Aug 23, 2020
205
69
38
Seattle, Wa
Jul 10, 2021
#6
  • Jul 10, 2021
  • #6
The rubber on the old one had begun to crack and I was getting some minor vibrations. I know it's wobbling because I touched a screwdriver to the flat surface on the front and the screwdriver would bounce from side to side as the balancer wobbled.
 

Hoytster

I don't dare do that to my Knob
20+ Year Stangneter
Dec 30, 2002
1,069
700
164
Cornwall, PA
Jul 12, 2021
#7
  • Jul 12, 2021
  • #7
keel said:
The rubber on the old one had begun to crack and I was getting some minor vibrations. I know it's wobbling because I touched a screwdriver to the flat surface on the front and the screwdriver would bounce from side to side as the balancer wobbled.
Click to expand...
So I'll go back to one of the original questions in my first post, did you verify it was the balancer itself that is wobbling, or are you looking at the pulley mounted to front of the balancer to check if it's wobbling? Also, if it is the balancer itself that is wobbling, did you verify it is wobbling from the hub or the outer mass? This will determine it it's a harmonic balancer issue, or something wrong with the crank or installation.
 
Reactions: Gs1987GT and General karthief
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