Home > Gear Oils
Since oil prices have been on the increase, it has been increasingly hard to provide gear oil at a competitive price. Therefore, I am no longer providing gear oil. Howerver, I've found that SAE 140 gear oil can be ordered from your local NAPA store (product number: SL 24228 [Stay- Lube SAE 140 Multi-Purpose Hypoid Gear Oil]) in the USA or SeagullParts.co.uk in the UK.
Always use straight SAE 140 and SAE 90 - not the modern SAE 85W-140 or SAE 80W-90 blends. Otherwise, you risk damaging your lower end unit gears. Oil is cheap, lower end units are expensive! NEVER USE GREASE!
If you are using your outboard in cold or freezing weather conditions, use SAE 90 grade in outboard models that use SAE 140. In tropical weather conditions a heavier weight gear oil of SAE 250 may be used - oil must pour.
Note: Make sure you know which gear oil is right for your outboard. All pre-1979 British Seagull outboard motors use SAE 140, and those manufactured from 1980 on use SAE 90.
To check the gear oil level, lay the outboard on it's side with the tank side up. Remove the filler plug (see diagram at right) with a coin or Seagull combination spanner. The correct gear oil level is at the bottom of the filler hole. To make sure the level is correct, stand the engine upright and allow any excess oil to drain out before replacing the filler plug. Do NOT over fill with gear oil. NEVER USE GREASE!