The oil pressure sending unit is important to know the amount of oil pressure that is built up within your engine. Low oil pressure is an indication that either the oil level is low or something is wrong within the engine. Replacing, or installing, a new oil pressure sending unit is not a hard project, but does require some time and removal of different parts on the engine. The actual location of the sending unit makes this project a little difficult for a backyard mechanic.
Step 1 - Read through Repair Manual
Sometimes before doing any work on something that you are not familiar with you should read through the repair manual. This will help to familiarize yourself with the different components of the engine and their locations. By doing so you will have a better idea as to what you need to remove and how do it.
Step 2 - Remove Air Breather
The air breather will need to be removed in order to access the rear of the engine compartment. The oil pressure sending unit is located in the rear of the engine underneath the distributor. To get to that part of the engine, remove the top of the air breather. This is done through either a wing nut, or simple clamps. Once off, lift the entire case away from the engine unhooking any wires or other relays.
Step 3 - Mark Spark Wires
As a part of the process you will need to remove the distributor of your vehicle. Before you do so, mark the spark wires so you will know how they will go back on. Use some tape and a marker and label each of the spark plug wires as to how they are configured on the cap.
Step 4 - Remove Distributor Cap
Pull the spark plug wires from the distributor cap and place them aside. Remove the cap and loosen the distributor. Lift this from its housing and set aside.
Step 5 - Remove Oil Pressure Sending Unit
Use a small wrench to remove the oil pressure sending unit. Make sure not to drop any screws or any debris into the lines. Disconnect the wiring from the unit and remove from the engine.
Step 6 - Install New Unit
Place the new oil pressure sending unit in place and connect the wire to the terminals. Place the screws into the right holes and tighten them to secure the unit.
Step 7 - Replace Distributor
Set the distributor back into position and secure with the locking nut. Place the cap back onto the part and follow the marks on your tape to reconnect the spark plug wires.
Step 8 - Replace Air Breather
Set the air breather case into position and connect the different relays and wires. Place the air filter back into the casing and secure the cover back on.
Step 9 - Set the Timing
Because you had the distributor out of the vehicle you will need to set the timing again. Use a timing light to get it as close as you can. If you need help take the vehicle to a garage for a quick timing adjustment.