It’s not uncommon for a tractor that has been sitting a while to become stuck. If your tractor’s engine is stuck from sitting, there’s a good chance you’ll be able to free the engine without resorting to an extensive overhaul (a tractor that becomes seized while running or is seized from running out of oil is a different story). While there are a few different methods for freeing a stuck (or seized) engine, here’s our favorite. First, pour a high-quality penetrating oil down the cylinders (through the spark plug holes). Use up the entire can, dividing it between each cylinder. Let it sit overnight. The next day, remove the starter to expose the teeth on the flywheel. Place a large bar in the flywheel and gently rock back and forth to loosen. If this doesn’t work – or if you are uncomfortable with placing a pry bar in the flywheel – try putting the tractor in a high gear and rocking the rear tires back and forth. Once the flywheel is loosened, do a quick tune-up on the carburetor. Re-insert the starter and spark plugs, put in fresh gas, and start the tractor up! There’s a risk with this method. Pry too hard, and you could break the teeth off the flywheel. However, I think it’s worth the risk. The way I look at it, if you tractor is stuck you are already in trouble. Your chances are pretty good of successfully freeing the motor with this method. I would use penetrating oil rather than engine oil, it has a better chance of freeing off stuck rings though obviously it will contaminate the sump, so change the oil (which you should be doing anyway after 28 years!) before actually running it
An engine can seize due to running on low/no oil, overheating or succumbing to a broken timing belt. These conditions eventually stop your engine in its tracks and a professional technician will be required to restore function. However, if an engine seizes due to rusted cylinder walls, you can restart the engine without professional help. This is how rusted cylinder walls develop: When a vehicle sits for an extended period of time without running, the lubricant coating the cylinder walls thins and drains away due to gravity. Shutting down a vehicle always leaves some of the intake valves open on some of the cylinders. This allows moisture-laden air from the environment to circulate through the engine's air intake, progress through to the cylinder head, and cause condensation on the cylinder walls, piston surface and rings. Left long enough, that condensation causes rust that can freeze the pistons in place, causing a seized engine. If you suspect that this is the case for your vehicle, this is how to fix a seized engine.
The crankshaft drives many parts located outside of the engine block. Disconnect any belt-driven accessories and parts under the hood. These parts, such as the alternator, water pump and power steering pump, increase drag on the crankshaft. Disconnecting them reduces the power needed to dislodge the pistons and allow the crankshaft to turn. This is how to protect your engine with additives.
Equalize PressureUse a socket to remove the spark plugs, taking care to number the wires as each is disconnected. You will need to reconnect each wire to its original cylinder when putting everything back together to keep the timing in sync. Removing the plugs releases any pressure within the engine that could push against you as you work to free the pistons. How often does your car need new engine coolant? Check the owner's manual and then check out how to change your engine coolant yourself.
Remove the Valve CoversUse a wrench to loosen the restraining bolts holding the valve cover in place on each cylinder head. Remove the covers to expose the rocker arms. Next, remove the nut holding each rocker arm in place and remove the rocker arms. Pull the exposed push rods out of the cylinder head. This step also reduces the resistance you must overcome to turn the crankshaft manually.
Turn The CrankshaftLocate the front of the engine block. On a transverse engine, this will be to one side or the other. At the front, you will find either a round harmonic balancer or a pulley that drives a belt. In either case, at the center will be a bolt head. To this bolt, attach a socket fitted onto a long-handled breaker bar. Turn the bolt in a clockwise direction to free the engine. If you cannot get the engine to turn, apply penetrating oil to the walls of each cylinder through the spark plug wells. Give the oil a couple of hours to work its way past the piston rings and try again. This process may require several applications over several days. If the car is equipped with a manual transmission, you can put the car in gear and rock it back and forth using the momentum to rotate the engine. These are 13 ways you're shortening the life of your car.
ReassembleOnce the engine is freed, work backward to reassemble the engine, replacing any seals or gaskets uncovered in the process of opening things up. Make sure the battery has a charge, then try to start the engine. If you can't get the engine to turn, the damage may exceed simple cylinder rust and you will need to make a decision on whether an overhaul is worth the effort to save the vehicle. Is your engine dirty? If so, this is how to clean a dirty engine. Originally Published: March 20, 2020
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