The first 8N Tractors were available in July, 1947. "8" was to designate it for the new Model Year, 1948. The early ones had a casting date code on the block, on the starter pocket, as Kirk showed. That is only the date the block was cast, not the build date of the tractor. The others stated other parts that have casting date codes too---axles, hydraulic pump, et al. Casting codes were part of the mold with cast raised characters on a boss tag applied to the sand casting. Serial numbers were hand stamped by a person AFTER the assembled engine passed QC Inspection and Break-in Testing. All this being sad, don't rely on s/n's for a positive ID. Engines got swapped out often. Unless you plan on doing a total, correct restoration, forget the serial number. Know the important features on your tractor to deal with the technicalities. Those are: #1 - Front Mount Distributor. These were used on all N's from 1939 thru April, 1950. At s/n 263844, Ford had made several changes to the 8N and the angle (side) mount distributor was one of them. This necessitated that the generator also be revamped as well and moved now to the LH side of engine. #2 - Early 8N steering box or the later version. In late 1949 Ford revised the troublesome Saginaw Steering Gear box to the later improved version. #3 - Electrical System. Is it the OEM 6V/POS GRN setup or has a 12V/NEG GRN switchover job been done? #4 - 4-Speed Transmission. The 8N introduced the 4-speed transmission, improved from the prior 9N/2N 3-speed tranny. #5 - POSITION CONTROL. The 8N model also introduced POSITION CONTROL to the standard hydraulic 3-point DRAFT control only lift system. Switching back and forth was possible via a lever located beneath the RH drivers seat. If ya just hasta know yer serial number, there are methods to try to decipher it. AVOID anything abrasive like sandpaper, wire wheel, sandblasting, et al. You can search the archives as this topic has been covered multiple times over the years. The serial numbers, being hand stamped by a man, often got weak and illegible especially after a long day of whacking a 5 lb. hammer with hand stamps. ALL 9N/2N and early 8N's serial numbers began with a STAR prefix and suffix to designate steel sleeves. ALL standard production 9N/2N tractors used the '9N' prefix in the serial number -no such thing as a '2N'stamped s/n. ALL standard production 8N tractors used the '8N on s/n's. Mid-8N production introduced the cast iron cylinder liners and now the prefix and suffix was a diamond symbol. No longer a concern today because they only make and sell the cast iron sleeves nowadays. It is strongly suggested you do not buy any engine kit when rebuilding your engine until you get it bare naked to see what is in there now. It may already have cast iron sleeves of which then the cylinders had to have been bored out for the larger cast .090 wall thickness units. Hope this clarifies things for you.
Tim *PloughNman* Daley(MI)