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#1
11-13-2020, 06:40 PM
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Vibration problem solved
Car is a 65 GTO with stock 389. No A/C. Went to install a crank pulley and water pump pulley designed for A/C cars to improve engine cooling at idle. It did but that's another story.
I've always had a vibration between 48-52 MPH. I checked the normal things like U joints pinion angle and the other things you need to check. Everything checked good. I removed the crank pulley and balancer from the balancer hub. I was shocked at what I saw on the crank pulley. The 6 bolt holes on the pulley were badly elongated. I also noticed that the 6 bolts that hold the balancer and the pulley to the hub were not very tight. The balancer holes and reinforcement plate holes were good. Put the new pulleys on and torqued the 6 bolts to 25 ft.lb as per the 65 service manual. Went for a test drive and ,to my surprise, no more vibration between 48-52 MPH or any other speed for that mater. I guess it just goes to show that with a 50+ year old unrestored car you have to think outside the box |
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#2
11-13-2020, 06:49 PM
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nice catch
b4 the implosion occurred the balancers also like to crack at the keyway too , seen on the seal side zoooom zoom Last edited by Scott Thelander; 11-13-2020 at 06:58 PM. |
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#3
11-13-2020, 06:50 PM
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Should be only 4 holes that thing was molested or from another make engine buggered up to somewhat fit
__________________
A man who falls for everything stands for nothing. |
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#4
11-13-2020, 06:56 PM
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thats the style thru 67 on the early 2 piece balancers
68 was first 4 bolt and new balancer,,, |
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#5
11-13-2020, 07:14 PM
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I dont have experience with early years just 66 and later, but it was sure buggered up
__________________
A man who falls for everything stands for nothing. |
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#6
11-14-2020, 06:57 AM
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Nice find, it's good that you stuck with it !
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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