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This is EXACTLY the condition my 9N had when I acquired it. Terrible knocking in cylinder #1 turned out to be a completely missing sleeve which was found in pieces down in the sump. Not to worry. This engine is really easy to rebuild. I did "in situ". Get the ITO FO-4 manual! (Tractor Supply, or this website can sell it to you.) Drain all the fluids. (gas, radiator, transmission-rearend) Jack up the front of the tractor and place heavy beams, (I used 16" I-beam drops left over from a metal bldg project) or railroad ties, etc. IMPORTANT: Do not use construction blocks or anything likely to crush or fail...You will have your BODY under this heavy thing! When the front end is off the ground a few inches, remove the hood/gas tank/radiator and unbolt the front axle from the engine. Leave the axle and steering attached and pull the axle forward a foot. (The wheels will turn inward,...so what? They"ll be out of your way. No need to completely disassemble the stuff.) Remove the head and oil pan (sump). Remove the rods/pistons and keep them oriented with each other. Note the orientation of the rod-caps on the rods also. Same thing with main bearing caps if you remove them. (Unless you want to go all-out, you might consider leaving the mains alone. But if you pull one main lower cap, you can read the part number on it to find what size to order with your rebuild kit, even if you do not intend to replace them. If no evident damage to the mains, I"d replace them with the same size, personally. I wouldn"t spend a lot of time micro"ing, grinding, polishing a crank unless there was damage. Just replace the bearings with new so you"ll have good oil pressure when this is all over. They can be replaced without completely dropping the crank, but the upper main oil seals are not as easy. Theres a tool, a so-called "sneaky Pete" that like a chinese finger-puzzle is supposed to enable you to remove/replace the upper oil seals. I"ve never found one that could do anything other than encourage skinned knuckles and expand your nearby young daughter"s vocabulary. (!!&^%$#@@#%) Be happy to replace just the lower half of the rope seal unless you"ve removed the crank and can access the uppers. Make sure when you install the mains/con-rod bearings that you lubricate them with Lubriplate engine assembly grease, or at the very least, clean motor oil. (Another good product is Permatex anti-seize, a silvery-slippery lubricant sold in a small jar with a brush-applicator, but it"s also messy.) Rebuild your oil pump. Don"t skip this. The oil pumps came with different size impellers/bushings/etc. so take yours apart and make measurements so you"ll know what parts to order. Do not expect to have to "bore" out your block. You"ll likely be able to do a very nice job without even removing the block from the tractor. Use an old screwdriver to split the sleeves and pull them out, and clean, dry, and inspect the bores. (Lightly hone any deep scratches if necessary, just don"t try to remove metal. A perfect finish isn"t important at this step. Just a clean, round hole is necessary.) Use a solid block of wood that completely covers the entire circumference of the sleeves, laid flat across the top of the new sleeves and a mallet to drive them in. Forget all the advice about "sealing" or glueing the sleeves to the block, etc. Not necessary and was never intended by the maker. No O-rings are used on the N Ford. A lip at the top of the sleeve fits into a cut-out ring in the top of the cylinder, and the head/gasket holds the sleeve in place. Just make certain that cut-out is cleaned out and not damaged before you install the new sleeve. With the sleeves installed, and the oil pump rebuilt/reinstalled, then put the new pistons on the rods. Pay attention to the bushings in the upper rod-ends which accept the piston pin. This should be a snug fit. If your old bushings fit the new pin snugly, then just make sure the lubrication holes are open/clear. (If your old rod bushings are worn, the overhaul kit will have new ones, but they must be properly pressed in and reamed. You"ll probably just want to take them to a machine shop for this work.) Use a soft brass or copper wire to push out the coked oil in the old bushing passageways. Lubricate the new pin with engine oil (or better yet, Lubriplate engine assembly grease) and install the pistons with their new rings. (Use 3 ring pistons is my recommendation.) Use a ring-expander (cheap $6 tool at Napa) to install the rings, and be sure to orient the rings with their open ends at opposite sides of the piston. (Before placing the rings on the piston you can push them down inside their cylinder to check end gap. You want about .005" minimum adn you can use a file if necessary. If you order your rings/pistons/etc as a complete kit from the same supplier, they"ll most likely fit without any trimming.) Use a ring compressor to reinstall the pistons in the cylinders which have already been lubed with engine oil. Protect the crank journals from being scratched by the lower rod-end bolts. Use heavy stainless safety wire or mechanic"s wire to lock your main/rod caps. (Some folks use cotters, but if you do, make sure they"re stainless.) I used Permatex #2 for gasket sealant except on the head gasket where I used nothing. Do not grind or "face" your head or you may create a piston/head clearance problem. Use a torque wrench and BE CAREFUL with the head bolts at the front of the head (toward the radiator near the center. A couple of them penetrate all the way into the water jacket of the block and if overtorqued will strip and then you"ll have a nasty coolant leak. Torque to the low value, in my opinion. See the ITO manual. Now is the time to make sure you have a healthy governor also. Rebuild the carb while you"re at it, and inspect your radiator and gas tank now while you have them off. This is the time to rebuild, replace, or clean/reseal them. New hoses should be used. Don"t forget to install engine oil and coolant. Now is the time to follow the manual to remove/rebuild the distributor and replace the points. It"s easy. Reverse the disassembly process of the steering/radiator/hood. Having replaced all the ignition components, plugs and wires, start "er up, and SMILE when she purrs. Now wasn"t that easy? (Took me a two days and a case of Becks beer.) ;Þ
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