Table of Contents
How To Restore A Classic John Deere
There are several steps to restoring a John Deere, depending on your skill level and budget. While every restoration project will vary, many general rules will apply. We strongly recommend the book How To Restore Your John Deere 2-cyl Tractor by Spencer Yost. This book is the definitive guide to any restoration project and can take you through the process step by step. (It also has pictures, which I dearly love). In addition, Spencer Yost has published many other books on restoring classic tractors.
Set A Realistic Goal
While it is lovely to be able to restore a classic tractor, not everyone has the mechanical chops to overhaul an engine. If you are a novice to these issues, enlist the help of a mechanic who can help you. Consider sending the unit to a repair shop so trained technicians can diagnose and rebuild the engine components or hydraulics.
This step is an excellent time to inspect the engine for any signs of leaks. While some leaks can come from faulty gaskets (valve cover gaskets are a big culprit), they can also be a sign of more serious engine issues (cracked block, thrown rods, bent valves). A leak is another reason that having a trained technician help you from the start because they can determine where the leak is coming from and whether it is worth repairing).
If you decide to jump into the restoration project, you must quickly determine how much needs to be rebuilt. Does the engine fire, or does the entire unit need to be pulled? Do you have the necessary tools to perform the work? Is there a clean place to work without getting parts soiled or exposed to dirt, dust, and debris? Is there enough room for organizing the parts as you pull them off?
Begin With The Engine
The engine is the most significant part of any rebuild. Once you have determined your goals and have a clean place to disassemble the engine, position the engine lift into position and secure the safety chains. You will want to use a lift (a tractor engine is not something you want to try and muscle on your own. Be safe by using a lift and wearing safety goggles while working on your tractor. You will likely have to remove the radiator to access the engine. As you perform these tasks, examine all hoses and belts to see if you need new parts for the rebuild. (There are times when you can reuse a hose or a belt, but more often than not, buying and installing new parts is the way to go).
Disassemble the Engine
Begin removing mounting bolts and brackets so that the engine can be removed from the frame of the tractor. Depending on what is wrong with the engine, you will need to begin to remove the flywheels and crankshaft pulleys. Examine the clutch assembly to determine whether it needs to be replaced.
Remove the Valve Cover and Inspect the Cylinder Heads
Many times the cylinder heads need to be machined, which is likely something you will need to have a machine shop perform. Depending on where you live and how much work is involved, most machine shops will clean cylinder heads for $200.
This step is a great time to inspect the valves (if you have smoke from the engine or the values appear loose, they will likely need to be replaced and adjusted once reinstalled). The nice thing about two-cylinder engines is that there are only four valves to adjust.
Inspect the Engine Block
Like any other internal combustion engine, the engine block can crack or show signs of weakness if overheated or stressed. Just because an engine rotates freely does not mean the block isn’t bad. Look for cracks or oil or coolant seepage. If the oil or coolant appears to be discolored, if the engine smokes (from burning off oil or coolant, then the block is likely cracked and no good. While there are many reasons for a cracked engine block, the primary cause is overheating, which causes the components to expand, and leak. Chances are you have issues with the water pump that will need replacing.
What can you do if you discover a cracked block on your tractor? Not much, other than getting a new engine. Since most classic tractors will have other issues on top of a cracked block, the repairs are expensive and usually not worth spending the money on. (If it was a new tractor and the crack wasn’t too large - it might be able to be repaired). Either way, a mechanic can tell you if it is worth spending money on replacing the block or just buying a new engine.
Remove the Pistons and Crankshaft
You must replace the piston rings any time you take the pistons out, along with the new wrist pins and journal bearings. The crank rods can often be reused, but you should inspect them to ensure that there is no evidence of bent rods. If the unit has a cracked block, chances are fair that the rods will have to be replaced as well.
Inspect crankshafts to see if they need to be machined. This step is a great time to work with a machine shop that you trust or replace them altogether.
Remove Fuel Lines And Rebuild The Carburetor
An engine will only run if it gets enough fuel. Remove the fuel lines, inspecting them for any signs of crimping or breaking. Remove the carburetor, and begin rebuilding it so your tractor receives the proper mixture of air and fuel. Replace all gaskets (trust us).
John Deere experimented with many different carbs during their production cycles, so it is
essential to replace the carb with an exact unit. The serial number is usually stamped on the throttle body bowl, so be armed with that information when you search online or visit your local parts store.
Some carburetor parts are almost impossible, but don’t let this dissuade your search.
Reassemble the Engine
Now is the time to take everything you have disassembled and put it back together. Again, this is a good time to enlist the help of a mechanic. If you are working independently, use the engine rebuild's restoration guide. Take your time. (It will take longer to perform a complete restoration than taking the engine apart). While John Deere two-cylinder tractors are easy to work on, you cannot do a first-class job without taking care. Many restorers label the parts and organize the parts so that they can more easily rebuild the engine.
Replace or Restore the Electrical Components
This step includes any needed electrical repairs, including the distributor, spark plugs, and wires. Once again, getting new points and spark plug wires. This step is an excellent place to replace the battery if needed so that your tractor will have the juice it needs to turn over.
Test The System
Once everything has been reassembled, then comes the moment of truth when you turn the key, and everything fires up. If the tractor does not work correctly, disengage the key and go back to work tracing the problem.
Depending on the issue, you might have to disassemble the engine again or tweak something like distributor points. Again, take your time, assess the problem, make adjustments, and work systematically to determine the issue.
