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Alright, next on the list of pedantry - tightening of the connecting rod cap screw/nuts. The bearings all look about like the one below, which seems to match what the manual describes for normal wear, so I'm going to leave them alone. The service manual says these of the 7/16 variety should be tightened to 60-65 ft. lbs. Questions on this,

- I assume these torque specs were for a dry (no lube or Loctite) installation. Can these nuts be reused, or should new 7/16-28 self-locking nuts be used? I will say, a quick perusal of McMaster doesn't show a lock nut for 7/16-28. Their two options are a regular 18-8 stainless steel nut and aluminum for that size.

- Either way, is it a good practice to use Loctite (red or orange) when installing these?

Anything else I should be thinking about when reinstalling besides ensuring the oil holes point toward the camshaft side of the engine? I've got the top and bottom rings facing the opposite side of the slot on the piston, and the middle ring facing the slot.

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You don't need Loctite on any of that. You can buy new nuts from McMaster but IDK if it's necessary. The torque, rinse off the heavy oil with gasoline or the like, and hit it with something like PB Blaster just to get it wet.

Remove each bearing shell from the cap one at a time, and clean the mating surface on both with brake cleaner so it's dry between the bearing and cap. This reduces the chance of a spun bearing. Obviously you must use oil or prelubricant paste on the bearing surface itself.

Those are Marsden nuts and used in countless applications throughout Packard (they were invented by a Packard engineer), then later by other manufacturers. They should be readily available online.

If I was that far in, and with new rings, I'd replace the rod and main bearing inserts. That would assure long wear, good oil pressure, and good oil control.

Here are the new nuts:mcmaster.com/94820A245/

As long as you can't thread the old ones on by hand, you can probably reuse them just fine. If they spin on no problem then it's best to replace.

Thanks, guys! I did just want to reiterate that I have the larger bolts that requires 7/16-28 nuts, which is only available from McMaster as a regular (non-self-locking) nut. I'll keep scouring the internet, and worst case, MM carries the nuts for $10 each.

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Only $10 each, a bargain!

I reused mine, haven't fallen off yet!

Fun fact, 7/16-28 is the same thread as the 55-56 dashboard bezels use. E.g. Headlight, Antenna, etc.

I have no clue where MM is getting them. Either NOS or they just had a bunch made sometime. Wonder how much it would cost from a place likeengineeredcustomnuts.com/

Regarding not falling off, that's why they used such an unusual thread. It's like extra-extra fine. 28 TPI is fine thread on 1/4" which is barely larger than half the diameter.

Nice! I will check that out. Worth looking into at the least!

I have several boxes in various sizes of the Marsden nuts at my other house but not sure if 7/16-28 is among the sizes. I was just there today but didn’t think to look but will try to do so next time. That said, the ones used on the rods are longer (taller) than a standard nut so unless you’re actually missing some I would use only the originals.