Packard Forum Index » Post-War (1946-54)

Thanks Tx that’s helpful! I’ll for sure try it though to date I’ve never been able to rotate via the fan belt but I usually rock the car in gear and that does the trick.

Also just confirming my head tolerances are in spec, some low spots between cylinders but none above .010, some between .006/.008/.010 but my understanding is that anything under .010 is considered acceptable.

The engine should rotate easily with the head off and the transmission in neutral.
I should have mentioned to put some oil in each cylinder. If you put very much in, it will probably run all over everything when the various pistons reach the top of the stroke. Avoid this by limiting the amount of oil in all but the cylinder you are working on, and keep the piston in that cylinder below the top of the bore.

You put a 1" wrench on the bolt that holds the vibration damper on, basically at the end of the crank. It should turn easily. Engine rotation is clockwise when facing the engine. It should turn easily that way.

Hi all, so thank you for the replies, I was able to get it all cleaned and together. The good news is that the head gasket seems to be working well, the car has some more pep and seems a bit smoother/better overall in that department. I followed Dave's article on the process and retorquing, just waiting for the final post 100 miler now but no leaks there. The car is movable and that's good at least. Some things I experienced about the reassembly that I'll say in case it helps others:
-I got to a point where I had to call it when it came to cleaning the block itself and the pistons because I was likely not cleaning it any more and just repeatedly wiping it down with no further benefit. The head, being out of the car, I did first and was able to get it ready to eat off of.
-I didn't realize the gasket would need some convincing to get over the studs, particularly the large one next to the thermostat housing. This made it bend all around but I avoided kinks or any major damage... still unexpected I guess in my head I naively pictured it sliding right on. Paired with the tacky copper spray, being outside in the driveway, and the heft of getting the head back on by myself, it felt a little like I prepped for surgery then had to crawl into the room on my hands and knees.
-I forgot that the stud behind the thermostat neck is super close to the neck flange itself which presents challenges, to the point where mine actually interfered with getting a seal on the neck flange gasket. Rather than untorque the head nut and reorient the washer (which had a side cut flat), I decided to grind a bit at the neck flange to get enough clearance, it looked like someone previously poorly did the same type of thing so I did a bit of a better cleanup and also tried to get the sealing surfaces of the bottom aligned a bit better too (without removing too much strength). Next I also needed gasket sealer like a permatex to really get that neck gasket to hold the water again, I knew this from when I replaced the thermostat before but just forgot and it cost me another day because you don't really find out until you get everything filled up and ready to start.

Unfortunately today I did need to refill the water after the heat started to build and I checked to find it low, so I might have a thirsty crack in the block. Still have some hope that it's the system working out air bubbles and filling the heater. But, given I did an initial refill after the short run before the final retorque, I think today's fill is most likely something else. Major bummer.

Plan from now, pick one of these "chemical magic" block sealers as a Hail Mary to buy more time. Long term is hoping a rebuildable good engine/block surfaces here in the NE. Here are my new questions:
-Does anyone have a positive experience with irontite or something similar? (I know they all have failures, but I'm trying to identify which ones have actually had some success).
-Does it make sense to bypass the heater for this sealing? I've heard they can be negatively impacted

I would bypass the heater before doing anything else. It could be leaking.

If you're losing water, look everything over very carfefully. External water leaks can be very sneaky.

If you have an internal leak, it could be a crack or you may still have a gasket issue. If the studs are clean, the gasket should slip down over them without much trouble. The studs need to be totally clean right down to the block and there should be no crud or rust around the base of the studs. It can be tedious to get the studs and the gasket surface of the block completely clean. It might be helpful to make a dummy head out of 3/4" plywood to install the gasket. Lay the head on a straight, clean piece of quality plywood, clamp it, and drill through the head stud holes and plywood with a drill bit 1/32 smaller than the bolt holes in the head. Then re-drill the plywood with a bit 1/32 larger than the head stud holes . Then use the plywood to help get the gasket down over the studs. If the plywood jams, look to see where it is hanging up, and see if the stud is bent or has scale on it.

Check for water in the oil.

You could have an internal leak. It's important to retorque at this point. 100 miles is a rough guide, and dependent on usage. The most important thing is heat cycles.

Re-torque, and try the stop-leak stuff, which works, I don't believe it will hurt the heater, those aren't that complicated in these cars.

Thanks all, I’ve retorqued according to the procedure, not enough miles/usage to do it the 5th time yet. The gasket is on otherwise I’d use the plywood technique, it’s not coming back off now. I will try a thorough check of the heater and maybe rig up a bypass valve, though I would think this much water loss in relatively short drives under 10 miles through a heater core would be noticeable.I think I’ll be using a ceramic sealer hoping for more time until I can afford an engine swap or a metal stitching repair/sleeve and valve. Unfortunately both of those will likely not make sense value wise. Buying another running 22nd is the smarter path but I’m going to have a hard time letting go of this car that I’ve poured so much of myself into.

About how much water do you lose on a short drive? (How long is short?)

If you are losing significant water internally, you should have steam/condensation at the tailpipe and probably water in the oil.

An engine losing water internally will usually missfire on one or more cylinders and is likely to show bubbles in the upper radiator tank when running.

After such an engine sits for a few hours after a run, examining each spark plug in turn is likely to show some evidence of where the trouble is.


Either a head gasket leak or a crack can leak only when cold, or only when hot, or only when sitting. Looking for evidence of which cylinder or which cylinders are affected can make diagnosis easier.