jbjennings
Captain
- Joined
- Jul 18, 2007
- Messages
- 3,903
Just thought I'd make a list of common problems I've noticed over time and ways to avoid them, and things to check if problems arise.....
Lower unit oil---check for seal leaks, condition of oil. If oil is black and/or opaque, it needs changing.
Fuel line and/or oil injection lines-----check for kinks, leaks, cracks, line retainers being present, and whether they're ethanol resistant or not. Leaking fuel lines could easily catch your engine on fire!
Recoil starter rope----check for rope condition. If rope appears worn or has excessive abrasions, replace it. If the rope breaks, it could easily break your recoil spring as well.
Spark plug check---- check for water on plugs, electrode condition, color of each plug. If water is found, a common problem is the inner exhaust cover is corroded and water is spraying into the cylinders through pinholes created by the corrosion. I worked on a 2003 40 hp Yamaha with less than 20 hrs on engine and only run in fresh water that had a corroded inner exhaust cover plate and was spraying water in all 3 cylinders, but still idling pretty good. A bad head gasket is also a possible cause. A tan color on the insulator of your plug is what you want. If you see melted metal on the plug--detonation is occurring that will destroy your engine. If the plug is gray or white, that cylinder is running lean and could lead to scored pistons/cylinders.
Engine compartment check--- A quick look for dirt dauber nests (if you live in the south) may save your engine. The dirt can break loose and be sucked into your carb. Any kind of leak in the compartment is something that needs to be addressed. Check spark plug wires for abrasion, under the flywheel for a leaky upper main bearing seal, corrosion on electrical connectors or wires (FIX IT!!!), condition of sound insulation on cowl--if it's deteriorating replace it or remove it.
Water pump indicator check----if it's not working, run some weedeater string up through the hole to clear any insect nests or trash. If you notice any change in the indicator stream--it's a sign of a problem. Watch for intermittent flow, steam in the flow, bubbles in the flow, etc. Some larger outboards won't allow indicator flow until the thermostat opens up--so know your engine...
Prop check--- remove the prop and check for fishing line or other stuff on the propshaft that could cut an oil seal. Also pay attention that the blades of the prop have no dents, breaks, or improper bends. Bent props can cause excessive vibration that can prematurely wear your seals out and lead to water intrusion.
Tank check--- Is your vent open? Do you have gray fuel line? If so, I hate that gray fuel line and recommend replacing it with the good stuff. The OEM fuel lines are worth the money--even though they're high priced. Fuel injection line from an auto parts store is better than the gray stuff. The inner liner of that gray stuff will get broken down by the ethanol in today's fuel and break loose, thereby fouling carbs. The gray lines also harden in cold weather and will snap in two easily. The pickup tubes in tanks sometimes split, and the check valves can start sticking in the primer bulbs as well, both resulting in no fuel getting to the engine.
Battery check-- Clean connections, loose connections, water in battery reservoir full, proper voltage, etc. I like to use a voltmeter to make a quick check of my battery before going fishing. If you left the switch on, etc., then you won't know the battery is dead or low charge until you get to the lake and the motor won't start without a voltage check. I like my batteries to have at least 12.6 volts when going fishing. If less, the battery needs a charge or is going bad. I get around 12.9-13 volts when fully charged.
If anyone has anything to add, feel free to do so. There's nothing worse than a ruined trip due to a failed outboard!
Hopefully someone will find this thread useful.
Lower unit oil---check for seal leaks, condition of oil. If oil is black and/or opaque, it needs changing.
Fuel line and/or oil injection lines-----check for kinks, leaks, cracks, line retainers being present, and whether they're ethanol resistant or not. Leaking fuel lines could easily catch your engine on fire!
Recoil starter rope----check for rope condition. If rope appears worn or has excessive abrasions, replace it. If the rope breaks, it could easily break your recoil spring as well.
Spark plug check---- check for water on plugs, electrode condition, color of each plug. If water is found, a common problem is the inner exhaust cover is corroded and water is spraying into the cylinders through pinholes created by the corrosion. I worked on a 2003 40 hp Yamaha with less than 20 hrs on engine and only run in fresh water that had a corroded inner exhaust cover plate and was spraying water in all 3 cylinders, but still idling pretty good. A bad head gasket is also a possible cause. A tan color on the insulator of your plug is what you want. If you see melted metal on the plug--detonation is occurring that will destroy your engine. If the plug is gray or white, that cylinder is running lean and could lead to scored pistons/cylinders.
Engine compartment check--- A quick look for dirt dauber nests (if you live in the south) may save your engine. The dirt can break loose and be sucked into your carb. Any kind of leak in the compartment is something that needs to be addressed. Check spark plug wires for abrasion, under the flywheel for a leaky upper main bearing seal, corrosion on electrical connectors or wires (FIX IT!!!), condition of sound insulation on cowl--if it's deteriorating replace it or remove it.
Water pump indicator check----if it's not working, run some weedeater string up through the hole to clear any insect nests or trash. If you notice any change in the indicator stream--it's a sign of a problem. Watch for intermittent flow, steam in the flow, bubbles in the flow, etc. Some larger outboards won't allow indicator flow until the thermostat opens up--so know your engine...
Prop check--- remove the prop and check for fishing line or other stuff on the propshaft that could cut an oil seal. Also pay attention that the blades of the prop have no dents, breaks, or improper bends. Bent props can cause excessive vibration that can prematurely wear your seals out and lead to water intrusion.
Tank check--- Is your vent open? Do you have gray fuel line? If so, I hate that gray fuel line and recommend replacing it with the good stuff. The OEM fuel lines are worth the money--even though they're high priced. Fuel injection line from an auto parts store is better than the gray stuff. The inner liner of that gray stuff will get broken down by the ethanol in today's fuel and break loose, thereby fouling carbs. The gray lines also harden in cold weather and will snap in two easily. The pickup tubes in tanks sometimes split, and the check valves can start sticking in the primer bulbs as well, both resulting in no fuel getting to the engine.
Battery check-- Clean connections, loose connections, water in battery reservoir full, proper voltage, etc. I like to use a voltmeter to make a quick check of my battery before going fishing. If you left the switch on, etc., then you won't know the battery is dead or low charge until you get to the lake and the motor won't start without a voltage check. I like my batteries to have at least 12.6 volts when going fishing. If less, the battery needs a charge or is going bad. I get around 12.9-13 volts when fully charged.
If anyone has anything to add, feel free to do so. There's nothing worse than a ruined trip due to a failed outboard!
Hopefully someone will find this thread useful.