Items you will need
Pliers
Funnel
SAE 30 oil
The Farmall H tractor was made by International Harvester from 1939 to 1953 as an all-purpose tractor able to cultivate up to 35 acres of row crops per day. Quite a few of these models are still on the job, and they're popular with collectors, so parts are still readily available. However, many routine maintenance procedures on these old tractors differ from the processes for modern machinery, such as checking the engine crankcase oil.
Park the tractor on a level surface and allow the engine to cool if it has been run recently to allow the oil to drain back into the pan.
Locate the two oil petcocks on the right side of the oil pan, located at the bottom of the engine block.
Remove the uppermost petcock by twisting it counter-clockwise by hand, or use pliers if needed. Set the petcock aside.
Stick your finger in the hole where the petcock was removed. Make sure the oil level is up to the bottom of the petcock hole.
Replace the petcock if the oil level is up to the bottom of the hole. Tighten it with pliers clockwise. If the oil level is low, do not replace the petcock and follow the next steps.
Remove the oil filler cap on the right side of the engine near the magneto if the oil level was low. Place a funnel in the oil inlet pipe and add SAE 30 motor oil until the oil level comes up to the bottom of the uppermost petcock hole in the oil pan. Remove the funnel and replace the oil filler cap.
Thread the petcock back into the oil pan by hand. Tighten the petcock clockwise with pliers.