ASE G1 Auto Maintenance and Light RepairMaintenance and Light RepairMedium
A technician is performing a routine oil change on a vehicle with a spin-on type oil filter. After installing the new filter, what is the MOST important step before starting the engine?
- ACheck for proper fluid levels in other systems.
- BTorque the drain plug to specification.
- CApply a thin film of new oil to the filter gasket.
- DPrime the oil filter with new oil.
Show answer & explanationAnswer & explanation
Correct answer: C. Apply a thin film of new oil to the filter gasket.
Applying a thin film of new oil to the filter gasket ensures a proper seal between the filter and the engine block, preventing leaks and making future removal easier. While other steps are important, this is critical for the filter's immediate sealing function.
Why the other options are wrong
- A. Checking other fluid levels is part of a complete service but not the most critical step *specifically* after installing the oil filter and before starting the engine.
- B. Torquing the drain plug is important to prevent leaks and overtightening, but it's not directly related to the *filter* installation's immediate integrity.
- D. Priming the oil filter (filling it with oil) is a good practice for some applications to reduce dry start time, but it is not universally required or considered the *most important* step for filter installation and sealing.
Oil Filter Installation
The correct procedure for replacing an engine oil filter to ensure proper sealing and function.
- Always use the correct filter for the application.
- Lubricate the gasket before installation.
- Tighten to specification (hand-tight plus a quarter to half turn, or torque wrench).
- Check for leaks after engine startup.
Memory trick: New filter: prep the seal, then tighten and check.