Ok I did a search and found nothing, I have 2 221 cubic inch 24 stud flathead engines so that puts them in the 1939 to 1942 year range, one has the twin rear crank slinger, the other the single with rope rear main seal. Can someone tell me what year they went to the single crank slinger with rope rear seal.
Is the intake manifold deck raised above the block deck or flush? Also are there bumps on the pan rail or is the pan rail flat down the sides of the block?
That matches up...I'm at work but memory says the seal castings for rope carry 29 prefixes, meaning 1942 intro. The slinger one for 24 studs carry 91, 1939, the year the big crank was introduced. Those parts allow swapping of either type crank into any long crank flathead '39-48, and of course '49-53 cranks into any of the same.
Another oddity...the 24 stud was introduced during the 1938 model year. '39-up use the main bearing size and long snout kept until 1953, but the 1938s only used the 1936-1938 crank that went into the last two generations of 21 stud engines. This had smaller mains and a snout roughly 1" shorter than the late one. The extra length was apparently to support the crank driven fan introduced on many 1939's. Looking at the front of a bare engine, the shorter crank is roughly flush with the hole formed by bottom of front cover and front of pan, the late sticks out about an inch.
Bruce, thanks for the info I originally thought I had a 59AB engine as it had 59AB cylinder heads fitted, but not 59 cast into bell housing which has H 5 3 11 cast. I was under the delusion that the single slinger rope seal crank was introduced in 1946 for the 59AB engine, but from what you are saying it was introduced in 1942, the con rods are marked 21A made in USA which from info I can find matches with 1942, the pistons are 3 ring units made in Canada ?? The engine looks like NOS standard bore and crank with no signs of wear, still has cross hatching on cyl bores, water gallery's are clean as a whistle.
41-42 blocks, to my knowledge, are the only years which had the "raised" intake deck as well as no freeze plugs in the pan rail, thus the smooth side down the block. Bruce is spot on with the single slinger rope seal being introduced in 42 leaving the 41 with the earlier version of the long snout crank. While not a 59 series flatly, these are great motors that represent the last of the pre-war cast iron in these United States. Posted using the Full Custom H.A.M.B. App!
Postwar30 all good info, seems like the 42 motor is basically the same as a 59AB except for the 3 1/16 bore, not that I intend to bore this block but do you know what is the maximum these blocks can be bored out to.
Cully, those flattys had a 0.040 tin sleeve in the bore from the factory. Egge use to make a set of pistons that would allow for sleeve removal, cylinder hone and run 'em. While I have never done it myself, the old timers I run around with say they'd take them out to 3/16 without issues. Considering I find some significant historical value in these engines, pre-war iron reference, I always return the 41-42's back to stock. The sleeves are readily available as are the original style pistons. Honestly, unless the sleeves/block are damaged I don't see a reason to destroy the history for another 5-10hp and likely another 10-20 degrees of operating temp in the Texas summer.
Postwar30 I could pm you for info, but in the interest of sharing information with other HAMB members, can please tell me who sells the sleeves and original style pistons.
In the prewar 24 engines, both 221 and 239 had mixed production use of the sleeves and conventional iron bores, with different spec pistons. A 42 221 in Australia is likely a military engine from same Canadian based WWII vehicle. I don't think the sleeves were used in wartime motors at all, but might well be wrong. Does this one have either a 3rd oil hole at rear or a circular boss where one could be drilled near the normal 2?? I think of that as a WWII mark, for the various filtered and cooled applications. Pre-1946 engines had slightly different valve angles than 59A (though I have heard it rumored that the change actually was made during the war on some of the last 21/29 types) and had different water holes in deck. Ford's postwar rebuild instructions called for minor drilling and use of 59A gaskets to modify the water flow to 59 style.
Bruce, the engine is not an Australia made unit, was already fitted in a 32 roadster imported from the US. Only has the 2 oil holes and the circular Bose, it does not look like sleeves are fitted, has the large triangle water jacket holes in the block. I was intending to use the small round hole 59A head gaskets, not sure if this will be a issues.
Ford update called for 59 gasket and redrilling of the vertical row holes in the head if prewar heads were used. If heads are postwar or postwar aftermarket, all you need are 59 gaskets without the big triangular holes. My belief is that the existence of the circular boss on a prewar type block means that it is actually wartime production...the boss then remained on all the postwar flatheads.
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