Outboard Engine Fuel Troubleshooting Quick-Fixes

Outboard engines are incredibly reliable these days, but they’re still subject to many of the same old fuel problems we’ve always had to deal with. If your engine is cranking but just won’t start and you suspect it may be a fuel issue, remember these quick-fix tips.

1. Inspect the ball in your fuel line, which can indicate a number of problems. If it’s easy to pump and doesn’t grow firm as you squeeze it, there’s a good chance your fuel line has a leak and air is getting in and/or fuel is getting out. When the fuel line is properly sealed, the ball grows firm after a few pressure-building pumps. If, on the other hand, the ball is so firm you can’t pump it, that tells you that fuel isn’t moving through the system. This could be due to blockage, air-lock (inspect the fuel tank’s vent and make sure it’s open), or a faulty connection between the fuel line and the tank or the fuel line and the engine.
2. If you’re sure fuel is getting to the engine, your next suspect is the fuel filter. It’s rare that an external canister filter gets so clogged that fuel won’t move through it, but many outboards have small (read: easily clogged) filters inside the cowl. Since these are out of sight they often are out of mind, and few boaters remember to regularly clean them.
3. If you’re sure fuel is flowing properly but the engine won’t fire or starts then quickly shuts down, you may have water in your fuel or an ethanol issue. In either case, there’s only one way to find out for sure: disconnect the fuel line at the tank, and bring a different tank of fresh fuel aboard. Then try to start the engine on the new supply. If everything runs right, you’ll have to drain the boat’s tank and fill it with fresh stuff.

Naturally, there are plenty of other problems that can keep an outboard from running. Be sure to read Strange Outboard Problems (and how to fix them) and Clogged Carb? This is How you Fix It, to learn more outboard tricks and tips that will keep you on the water.