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

That could be a game changer, every shop I’ve talked to won’t consider any block work without the engine being out of the car. Napa did this?

Certainly tools and skills to install hardened valve seats with a flathead block in the car were commonly available and it was routinely done. But I can't say I ever heard of installing cylinder sleeves in that manner.

It has to be a Napa that has a machine shop (some do; most do not) and it was located very near my outdoor storage in San Jose, CA. Where my shop is now in Oregon, the closer Napa in Redmond does not have a machine shop (they can press wheel bearings but that’s it) while the one about 40 miles away in Bend does and just recently rebuilt the engine for my 1965 Imperial LeBaron.

It's unusual to have a crack at an intake valve seat. Are you certain it's a crack?

A significant head gasket leak will usually show some indication on the gasket itself or on the surfaces it contacts where a leak is. The cylinder or cylinders affected by the leak will usually show some indication, too. In some cases, a cylinder may be free of carbon when the others aren't, or rust or other staining may be evident, or the spark plug will look different from the others. A head gasket leak often causes rapid rust-up of the cooling system, and coolant may turn rust colored.

Valve seat area cracks often don't reach the water jacket, although some certainly do.

It's possible the crack has nothing to do with the recent symptoms, and you just have a head gasket leak. An intake valve might run a good while with a cracked seat without burning. Uneven torquing or overtorquing the head could possibley lead to a crack at an intake valve seat.

An exhaust valve will usually burn pretty quickly running with a cracked seat. A burned or warped valve can cause a cracked seat, as could a rusted or clogged water distribution tube, or an overheating incident could cause it.

For what it is worth, I have in a 54 327 just now with an humongous crack between intake and cylinder. The perpetual steam cleaning in the cylinder makes for a lot of ugliness. Will add a picture later today.

You can surely patch the thing up enough to move the car with a new head gasket and some chemical magic and it might surprise you with how far it will go.

Straight eight engines are readily available. ANY 48-54 288 or 327 block with 5 mains will do with the addition of your front motor mount details and water pump.
Those overly concerned about originality usually can't get their walkers close enough to the car to raise a fuss.

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My 1952 had crackers on at least two cylinders running through the valve seats.

It would be great if the crack happened to be coincidental with the head gasket leak, the suddenness of the coolant loss without a major overheating event is what gives me some hope with that. The gasket has some indications of being blown between cylinders for sure, and some suspect water passage areas. It’s a little confusing to know on the parts that got mangled/split during disassembly.

Ross, chemical treatments meaning the water passage additives/treatments? I did also consider using some space age ceramic metallic epoxies which seem to work well above the combustion temps and fix cast iron cracks in things like blast furnaces and turbines, but the ones that seem to meet all the criteria also need heat curing around 200 degrees for a few hours. Aremco pyro putty is what I was close to trying.

I’d appreciate seeing another crack that’s in a running engine if only to make me feel better about this one!

It seems unlikely to me that a crack would suddenly occur, especially across an intake valve seat, unless the engine was severely overheated or the water jackets frozen at the time. I'd think it far more likely that a head gasket failed. Is the old head gasket steel over asbestos? Steel faced gaskets can corrode while sitting. Copper faced gaskets can also corrode, but they usually don't. K&W used to offer a pretty good head/block sealer product. I'd install a new gasket, making every effort to do a proper job, including cleaning everything surgically clean and checking the head bolt lengths carefully and making sure the bolt holes in the block are clean to bottom and have good threads. Then add water only for coolant, and run the engine and do the retorque procedures by the book. If it still leaks, you have a problem, and one of the block sealer products might be worth a try. Don't overlook the possibility the head is cracked. It's not likley, but it can happen. Clean it up and give it a good looking over, paying close attention to the block side of the head.

The old gasket was steel, not sure if it is over asbestos or not.

Is there some trick to cleaning out the pistons? I have the shop vac, rags, cleaning sprays of a couple kinds and some brushes plastic and wire. It seems like gunk is going to get in between the piston and the wall above the first ring but I don’t have anything that can fit running through that tight space… a feeler gauge maybe plus shop vac hovering above? I don’t want to damage anything.

The best way I know of to clean loose debris out of the space above the top ring and between the piston and cylinder wall is to start at #1 cylinder, and use the fan to move the engine in the direction it runs just enough to move the #1 piston down about 2 inches from the top of the bore.

Then pour about an ounce of cheap, clean motor oil or ATF on top of the piston, or enough to completey cover it about 1/8" deep. Then use the fan to rock the engine back and forth far enough to move the piston up and down about an inch or so, but keep it below the top of the bore. This action will cause much of the debris to be lifted out of the space around the piston by the oil and left clinging to the cylinder wall.

Mop up the oil and debris with a clean rag, then repeat, adding more clean oil as needed. Repeat the process until only clean oil is left on the cylinder wall when the engine is rocked.

Then move on the next cylinder and repeat the process. Change rags as needed.

Avoid turning the engine full turns backward. Doing so may cause the oil pump to lose prime.

This process will remove most loose debris above the top ring and will help flush any remaining debris from around the second and third ring.