What to know about the Distributor O Ring:

The distributor plays a vital role in creating power for your vehicle. It accepts electrical pulses from the ignition coil and disperses them to the proper spark plug through the spark plug wires, which ignites the air/fuel mixture in the combustion chamber. The distributor shaft is fixed in the engine, either through the intake manifold or into the engine block.


Any amount of moisture inside the distributor can and will cause an irregular run and loss of power, so it is critical to keep it as dry inside as possible. There are actually two seals on the distributor shaft; one seals the shaft to the intake manifold or block to stop external oil leakage, and one is a shaft seal where the distributor shaft enters the distributor housing to stop oil from entering inside. Both seals are planned to keep oil inside the engine, not in or on the distributor. When the distributor o-ring in the intake is leaking, oil and grime builds up on the exterior of the distributor and the intake. If the distributor shaft seal is leaking, oil enters the distributor up the distributor shaft, albeit in small amounts, and stops the proper transmission of the ignition spark. This will cause the engine to misfire and run poorly, along with a lack of power.


Facts to Note:


Pulses of high voltage electricity go through the distributor and spark plug wires. Detach the battery before servicing the distributor.


How to Fix:

The Distributor O Ring is confirmed that it needs to be changed. The battery is then disconnected and the distributor cap is detached.


The distributor is removed and the faulty Distributor O Ring is detached from the bottom of distributor.


After the new Distributor O Ring is fixed and the distributor is reinstalled, the engine timing is set


The engine is started and the Distributor O Ring is tested for leaks.


The vehicle is road tested to ensure proper operation of the Distributor O Ring and timing.


Our Proposal:

The distributor cap needs consistent servicing and inspection during an engine tune-up. If oil is observed in or around the distributor, the distributor o-ring or shaft seal will need to be changed by one of your expert technicians. Sometimes the distributor itself will need to be changed if the seals are not serviceable separately.


Common symptoms indicating you may need to change Distributor O Ring:

Noticeable oil leak at the base of the distributor by the valve cover

Rough run and loss of power

Importance of this service:


An external oil leak from the distributor o-ring is almost always a minor concern that can be addressed in time. An internal distributor oil leak needs to be addressed straightaway as it can lead to power-robbing symptoms which can leave you in a dangerous situation while driving.