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Old January 29th, 2017, 11:28 PM
1972RedNeck 1972RedNeck is offline
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Default Re: 478M Loosening Rod Bolts

Quote:
Originally Posted by bluestreak1854 View Post
the 401 and 478 have an externally balanced crankshaft-- that means that the flywheel and harmonic balancer have the counter weights on them-- if someone has the wrong flywheel or balancer on this engine it could be sending vibrations that are loosening the rod nuts-- but the vibration should be very noticeable
That is definitely something to check.

Also, only the 379, 432, and 478 have externally balanced flywheels. The 401 should be the same crank as a 305 and 351.
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