Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Disconnect the spark plug for safety, then remove the oil cap and tip the mower with the air cleaner up to drain the oil through the fill tube. Use 20 oz. of SAE 30 detergent oil with an API service classification of SF, SG, SH, SJ, SL, or higher. to refill it.
Hope this helps!