Cont. from page 2
In the 59A block family there are several casting series, with some of these commonly regarded as possessing heavier cylinder walls and other heavy-duty attributes. In addition to the 59A and 59AB cast on the bellhousing of passenger car blocks, designations Y, L, and Z are also found, designating industrial applications. But, in spite of the lore that says the industrial blocks are better than the passenger car blocks, sonic testing of the cylinder walls proves that this is not the case. Dave speculates that perhaps the industrial blocks were thicker than passenger car blocks when they were new, but through 50-60 years of use they have been steadily rusting away in the water jacketing, and while some received better care than others, they are generally no better today than good passenger car blocks. "You don't know what you have until you clean, magnaflux, and measure them sonically," he says. In the later engines, the C8BA ('49-'53) was a commercial version of the 8BA and CM engines, and these blocks appear to be heavier, better quality castings. Dave has several in the shop that he has tested and found that they are definitely heavier. The individual foundry played an important role in the quality of the casting, he points out, such as the Canadian castings that have a higher nickel content than domestic blocks. In Dave's experience, the '49-'50 castings are not as nice as the '51-'53 castings, and the Mercury blocks are generally cleaner than the Ford blocks. He speculates that while they probably were produced with the same tooling, the better blocks were allocated to Mercury. And speaking of the later Mercury, it has a very desirable hot-rod piece included in its basic package - a stroker crankshaft. All of the earlier cranks, both Ford and Mercury, are 3-3/4-inch stroke, while the stroke of the '49-'53 Mercury crank is four inches - 1/4-inch more arm' at no extra charge in a Mercury engine.
From the outside, there's no indication of the interesting work that takes place in these two old barns. Disassembly and cleaning operations are carried out in the one in the foreground, while the other..
..Houses a modern full-service engine machine shop, display area, and engine-assembly clean room.
TEARDOWN
Like most engines, the as-found condition of a flathead will determine the degree of difficulty in getting it separated into its component parts. For a tired runner that's just been taken out of service it's likely to come apart routinely, although don't count on all the head bolts or studs unscrewing neatly; a snap-off or two isn't uncommon, and the remaining pieces can be removed later, in the machine shop. For a non-runner that's been sitting for an indeterminate period of time, particularly if it's very rusty, a thorough and long soaking in penetrating oil, such as Liquid Wrench, or stove oil, or diesel oil is essential. When Dave talks of a long soaking he's speaking of two weeks to a month to allow the oil to do its work and free up the pieces. Valve assemblies cause the most trouble, even with the aid of the obligatory valve bar, and if you can remove all 16 without resorting to a ‘heat wrench,' count yourself lucky. Stubborn assemblies are usually dealt with by either disassembling from the bottom - removing the keepers, the spring, and pulling the valve out from the top - or cutting off the valve head with a torch if the valve is also stuck - to disassemble it, and then driving the guide down and out of its bore from the top. As you would with any engine, identify the main-bearing caps and connecting rod assemblies for location and direction.
BLOCK
Cleaning & Inspection: Block cleaning and inspection should be done in interrelated steps so that unnecessary time and money won't be spent on an unserviceable block. For example, it makes no sense to pay to have a block acid dipped --- an essential step in the cleaning process - if the block has unrepairable damage. Conventional hot-tanking alone will not clean the block well enough, but hot tanking or jet washing or steam cleaning, is sufficient to permit visual and magnaflux inspection for stress cracks in the deck, in the reliefs between the valve seats and the cylinders, as well as stress cracks in