Re: What size vibration damper bolt head do you 356 owners have?

Posted by su8overdrive On 2024/2/22 0:32:39
Thank you, gentlemen. Your detailed candor underscore that Packard was indeed "A gentleman's car, built by gentlemen."

Both the 356 bolt #341404 head size 1 3/4" and the junior # 304128 head size 1 1/4", are, other than head size, identical: 3/4-16. The senior bolt's additional 1/2 inch head width allows it to forego a washer since it has more metal against the vibration damper, albeit it being a thinner head than the junior bolt, which calls for a lock washer.

Just discovered my engine has a 1 1/4" vibration damper bolt head. A lifelong Packard wrench tells me it doesn't matter what size bolt head i have. Assume this another case of Packard's over-engineered overkill? The junior vibration damper is a few pounds lighter, but that's the only difference.

Sure, the perfectionist, OCD in me, beloved of factory standard, would like to have the 1 3/4 bolt. But given there's only 2 3/4 inches between the face of the vibration damper and radiator in my '47 Super Clipper, and the car's traveled 16,000 miles since hot tanking, machining, balancing, assembly by my late mechanic's mechanic, who ran motor pools in the War II Pacific, then worked at a Packard dealer before my car left Detroit, then various Hudson dealers setting up winning cars for the Capitol and Sacramento speedways, then a Pontiac dealer before starting his own renowned shop in 1958-59; and given the above's assurance it doesn't matter, i am sorely tempted to live with 1 1/4. What think you?

BDeB's experience using a 3/4" drive doesn't surprise. For those with a 1 3/4" bolt head, you'd think a 1/2-inch drive 1 3/4" socket would fit that cramped space given the 1 3/4" bolt head is thinner than the 1 1/4" junior and doesn't have a washer and lock washer, is recessed in the damper cavity. The 1 1/4" bolt head protrudes slightly.

Meanwhile, MJG, i f it comes to yanking everything out, consider lightening your flywheel. I've heard a Packard maven report doing so to a 356. Wish i'd so done mine when for the sake of an effing $18 pilot bearing which squalling would wake the dead, we had to remove the transmission, so thought i'd replace the F-series Ford truck clutch so many 356 owners use, for a Packard pressure plate rebuilt using the original jig. As long as we were in the neighborhood. But, my flywheel's still stock weight. I bow to others' insight regarding this and don't want to give MJG a bum steer.

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