Restoring a Kubota B20 Tractor – Part 2

You can find part 1 on this rebuild here.

Update: I have tires and wheels on the Kubota B20 and aired up. Was able to get 3 of the 4 to hold air with some tire slime. Front left still has a slow leak that I am hoping will seal up once I get it rolling.


Changed the engine oil, oil filter, air filter, fuel filter and radiator fluid.

Engine was completely seized and would not turn over. Removed the injectors and squirted sea foam and engine oil into the chambers to let sit for a couple days. Still wouldn’t crank over with the starter so I used a wrench on the flats of the crankshaft / hydraulic pump shaft coupler to work it loose.


Also needed a new fan belt. Side-note – Not an easy job on these machines. If I ever need to do a belt on a machine set up like this again, I am using one of these:

Engine now cranks over and after lots of working the air out of the injector lines sounds like its firing on one cylinder, but not enough to start. It was in the low 40s (F) when I was attempting, so I plan to give it another try on one of the upcoming warmer days.

Part 3 on the Kubota B20 Rebuild.

Restoring a Kubota B20 Compact Utility Tractor and putting it back to work!

A friend of mine has this tractor that was been sitting unused for several years. It ran when it was parked, but at the time it was having some overheating issues, as well as we suspect at least one of the injectors was leaking down causing a surge of heavy smoke for a few minutes when it would first start up.

I am going to go through it and get it back up and running. Once I get it back operational again, I may also consider setting it up to run on waste fuels such as used vegetable oil, motor oil, etc.

Kubota B20

First up is get the front tire back on it (was borrowed to be used as temporary spare for a different tractor),new battery, and get the supplies together to change out the motor oil, and coolant.

Kubota B20

It definitely has been sitting for a few years!

Kubota B20
Kubota B20

The hours meter has definitely turned over at least once. I am also not sure what the expected lifetime is on these Kubota 3 cylinder diesels.

Kubota B20 Hours

The engine compartment isn’t too bad. There is a mouse nest in the coolant overflow bottle though!

Kubota B20 Engine

Should be a fun project! Click here for part 2 on the Kubota B20 project.