In Old Small Farm Tractors, Lubrication is Key
Keep Your Old Tractors and Machinery In Top Shape With Simple Maintenance
By Dave Boyt – Call me sentimental, but I have a soft spot for old small farm tractors and here’s why. Just a couple of weeks ago, my wife, Becky, surveyed my latest acquisition, a nearly four-foot diameter by 10-foot oak log that I had salvaged from a residence in town after it had died and a tree service company cut it down. The two-ton log was sitting on a trailer behind “Scotty,” my ‘87 Chevy pickup. “How are you going to get that monster off the trailer and to the sawmill?” she asked skeptically. “No problem,” I replied. “Henry and I can get it all right.” “Henry?” she scoffed. “When is the last time you managed to get any work out of him?” “I just need to get him gassed up and choke the daylights out of him,” I replied indignantly. “He’ll pull his weight, and then some.” Henry and I have worked together for over 40 years, so we pretty much know what to expect from each other. And yes, sometimes it involves choking … and kicking … and all manner of verbal abuse, to which “Henry,” my 1951 8N Ford tractor appears indifferent.
Henry is a fine example of one of the most successful and versatile small farm tractors ever built. Though not ideally suited to any specific task, the 8N is sort of the “Swiss Army knife” of small tractors. Equipped with a front-end loader and various other attachments, it can lift, haul, plow disk, mow, power a generator, and even cut firewood. Henry is by far the best tractor for small farm tasks that I’ve ever had, and he has served me well.
Naming my equipment, by the way, is a trick I learned from Becky. She brings home stray dogs, cats—even turtles—and, before I have a chance to protest, she informs me that she had already named it. Somehow, that makes it official that it now belongs with us. So now, when I pick up a “new” piece of equipment at a farm auction, I have a name for it before it comes in the driveway. I have never understood how the same hopeful eyes that persuade me to keep a stray dog can give me the “woman look” before rolling heavenward when I proudly show her my latest acquisition.
Growing up on a farm in central Iowa in the 1960s meant that keeping old equipment running, including our small farm tractors, was a way of life. We didn’t have duct tape or WD-40 back then, but we had a plethora of bailing wire and used motor oil — you know, common farm equipment. Old farm tractors and other farm machines, like their owners, can be temperamental and finicky, but once you understand them, they can be hard working and reliable friends. Maintenance of these small farm tractors is actually pretty simple, compared to their modern counterparts. With only a screwdriver and pair of pliers, you can replace the ignition system. Add a set of wrenches (American wrenches, none of that metric nonsense), and you can overhaul the engine. That’s how they were designed. If you are fortunate enough to have such equipment, proper lubrication is the key to keeping it on the job.
The engine is the heart of the tractor, and certainly the most complex component. Check the oil level at least every 10 hours of use. The tractor engine has a dipstick somewhere on the side. If the oil on the dipstick appears milky white, it has water mixed with it. Change the oil and check it again after you have used the tractor a few hours. If the oil appears milky again, the head gasket is leaking, or the block is cracked and needs repair. Change the oil (and oil filter) on a regular basis. I try to remember to change the oil twice a year, and the filter once a year. Check the oil requirements for your truck or tractor engine. Older tractors should have straight 30-weight non-detergent oil. Detergents in modern oil can loosen up sludge that has formed over the years, which can clog up oil lines and cause bearing seals to leak. There are also oil additives that are designed for high mileage engines. Lucas oil products have a good reputation for increasing the compression and stopping smoking.
Somewhere on the tractor is a dipstick (possibly several) for checking the transmission oil level. Check this every month or so. The transmission oil on many tractors also serves as hydraulic oil (called “universal” transmission oil), so make sure you use the type recommended for your tractor. Water in the transmission/hydraulic oil can crack the hydraulic pump when it freezes, and replacement pumps for old tractors are getting hard to find. To check for signs of water, examine the dipstick for a milky fluid every time you check the oil level. In the fall, loosen the drain plug just enough to let some oil out. If water comes out, or the oil appears milky, go ahead and change it. A five-gallon bucket of oil will set you back around $75, but that is a lot cheaper and easier than replacing a hydraulic pump. There may be several drain plugs, so make sure to drain all of them.
Although not part of lubrication, many older small farm tractors use an oil bath air filter. This should be checked and cleaned out every month or so, and the oil replaced every year. The last time I checked Henry’s air filter, it had acorns in it, no doubt deposited by an industrious mouse.
Finally, many small farm tractors have a gearbox for the steering. Follow the shaft from the steering wheel. If it goes to a box with a bolt on top, remove the bolt, and fill with 90-weight gear oil.
Then there’s the grease. Grease serves two purposes. It lubricates the part, and drives out moisture. If you don’t have a grease gun, you can buy one at a farm or automotive store. Get a couple of tubes of grease, while you’re at it. You don’t need the high performance stuff, since it didn’t even exist back when the tractor was built. The grease gun should fit onto the fitting (called a “zerk”) tightly. For the most part, simply add grease until you see it oozing out from around the joint. Wipe off the excess, and go on to the next one. I generally start at the front of the tractor and work my way back.
Wheel bearings (front wheels on tractors and trailer wheels) use special bearing grease, which comes in a can. To apply grease to the wheel bearings, you will need to remove the wheel. Make sure the tractor is in gear, the wheels chocked, and the brake set. There should be a metal cover over the bearing that either screws off or comes off with persuasion from a screwdriver (sort of like opening a paint can). A “castle” nut with a pin (usually bailing wire) holds the bearing in place. Remove the pin, unscrew the nut, and the bearing should slide right out. If the bearing is dry and rusty, appears damaged, or has rollers missing, replace it. When I took the hub apart to photograph the process for this article, the rollers promptly fell out of the bearing, so it was a quick trip to the auto parts store for a replacement! Greasing bearings is a messy job, so have some extra rags handy. Put the grease in the palm of your hand and roll the bearing through it to work it into the rollers. Then wipe some grease onto the bearing surface in the hub. When re-assembling the hub, tighten down the nut just enough so that there is no play in the wheel when you wiggle it (usually finger tight), then re-insert the pin, using the closest gap in the “castle”. When you replace the wheel, by the way, do yourself a favor and put a little grease on the threads of the stud bolts so you won’t have such a hard time removing the wheel next time.
Sometimes in the morning, I wish I had a few grease zerk fittings so I could lubricate my joints, too. But as long as I can convince old Henry to pull his weight around the farm, I avoid the heavy lifting and give my 60-year-old joints a bit of a rest. With proper care, there is no reason why my grandson can’t use Henry when he gets to be my age. Lubrication of old small farm tractors is the key to ensuring a long and healthy life.
As a final note, manuals for the most common small farm tractors are available at farm supply stores or online. There are also a number of online forums where you can ask questions and benefit from the experience and wisdom of experienced mechanics. A couple of good ones are My Tractor Forum and Yesterday’s Tractors.
Author’s Bio: Dave Boyt has a degree in forestry, operates a sawmill, and manages a certified tree farm in southwest Missouri. He has been working around tractors most of his life.
Originally published in Countryside January/February 2015 and regularly vetted for accuracy.