THE JOHN DEERE UTILITY TRACTOR
A few years ago we had retired the well used John Deere lawn tractor that my mother had gotten back in 2006. Obviously for all intents this machine has long since outlived its normal life expectancy. It was having little issues that more or less continued to cost us money in the form of replaced parts several times a season. Not to mention the capability of the machine wasn't as great as the zero turn that we ended up picking up as the replacement for this old tractor. From there the machine sat in the front corner of the garage accumulating dust.
Fast forward to now and after looking at this thing enough, I decided I may as well do something with it because we wouldn't get much for the machine in the current state and I already know there really isn't much wrong with it short of being an old machine. My solution, turn it into a utility tractor for around the yard and grounds. I had recently picked up a utility trailer that can hitch behind the tractor and this combo would be perfect for those jobs such as yard work where we need to haul bundles of branches or other trash from a work site to a staging area for disposal. This machine could even serve as a mule for moving small cargo between neighboring houses in lieu of using a regular truck. The main thing is that we have to restore the machine to regular operation, while doing some other converting work.
This lawn tractor is an 18.5HP single cylinder front engine mounted machine with a 42" twin blade cutting deck. My first plan was to remove the cutting deck as it would not be used anyway. For where the tractor would probably travel, the deck would be a hindrance. After pulling the deck free from under the machine the next move was to start doing the typical service style work, such as draining oil, changing the spark plug, fuel filter and draining the old gas from the tank.
I conveniently had some leftover components from some service kits I had ordered in the past for the zero turn and the whole house genny my mother has, both of which use the same size Briggs engine, which used the same spark plugs and in the case of the zero turn, used the same fuel filter. I even had a couple of small bottles of oil to use. I also had a couple of replacement spark plugs.
The first thing that came out was the fuel filter. A simple swap out, the small filter was taken care of, allowing me to quickly move to the spark plug. After finding the location of the plug I pulled the plug, examining it. Surprisingly it was in good shape, electrodes weren't burnt away. But being rusty I still replaced the piece. The next area of address is the carburetor.
The carburetor needed to be pulled with the intake tubes still attached in order to remove the two bolts that hold the carb to the intake pieces. There were only two bolts holding the downstream intake tube to the engine so after pulling that free the other tube popped free as well. After removing the linkages and the fuel cut off solenoid I had the assembly out in the open. From there I was able to get the two nuts pulled free to remove the carb from the intake tubes. With the carb free I was better able to match up the old piece to a new replacement piece to make sure I get the right item.
With the carb out of the way and the oil drained, I was better able to get my hand around the oil filter to spin it out. After removing this thing my next order of business was draining the fuel tank. Since the fuel was probably over 5 years old, there was no chance in this fuel being any good except for fire starting fuel. I had to examine hoe the hose goes from the fuel tank over to the engine.
While I was able to route the fuel hose through the hole in the frame and out towards the back to give me more hose to work with, I would've had to remove the whole top shell from the tractor in order to be able to get the fuel tank completely removed from the machine. As this wasn't feasible, the next best thing would be to use the siphoning effect of this design to my advantage to remove the old fuel.
Now a little on the design of the fuel system on this tractor. The engine has a little fuel pump that draws fuel from the tank. On the tank the hose actually connects to the top of the fuel tank and inside the tank there's an internal tube that goes down to the bottom of the tank to pick up fuel. When the fuel pump starts drawing fuel the siphoning effect further allows the fuel to draw out of the tank which is mounted higher than the fuel filter and carburetor on the engine.
Because of how this system is set up, it didn't take much to get the fuel to start flowing. I only had to lightly draw on the open end of the fuel line before old fuel started flowing, which is good, I don't want to taste fresh gas much less 5 year old gas. Since there wasn't much gas in the tank, the tank drained out fast but since the pick up doesn't touch the very bottom of the tank, a little gas remained. This is fine as I'll put fresh gas in the tank to dilute the remaining old stuff to where it won't affect anything.
As for the battery, this didn't take too much effort to remove. The cables/terminals were held in with simple nuts and bolts. Despite them being rusted and giving me some grief, I was able to get them freed up and separated so I could pull the old battery out. Because this battery is 5+ years old there is no possible chance in my opinion of reconditioning this battery to where it can even be restored to a partial level of normal use as with a brand new unit. This battery has to go.
Now that we got everything removed from the tractor, it will be time to start ordering parts. I have to get a replacement carb, oil filter, battery and maybe the hardware for the steering mechanism. After examining the steering everything still looked relatively fresh. I'll try oiling everything up and test out the steering to make sure it does work properly before ordering these specific parts. At least when I do get the initial components the tractor will be all good.
After installing the carburetor and other parts, we were able to get the tractor running for a short time. It was then discovered that the fuel pump had to be bad due to the engine sputtering from fuel starvation. After replacing the fuel pump I still had to do a little adjustment. The engine had a hunting idle/hunting RPM issue between the governor and the carb throttle. Even after manually manipulating the governor the engine would sometimes run full RPM and sometimes not. Unlike some engines that don't have these internal governors, this type of small engine can be finicky, sometimes requiring some finesse to get it to act right. In this case I ended up adjusting the idle screw all the way in so the carb throttle was unable to throttle down much. While this would have a non governor engine racing at high RPM, the governor plays a major part in the engine speed. Even with the throttle at a wider open position, the engine was still able to be throttled down to a lower RPM with the throttle linkage working the governor. Of course with this bootleg way of "fixing" the problem, the engine seems to prefer running at full/high RPM. Of course this is fine since the tractor's speed is controlled via the fluid drive transmission while the engine runs at a fixed RPM at all times. At this point the John Deere Utility Tractor is ready for normal use.