Why is my Yamaha outboard overheating?

A: A faulty water pump is a major cause of overheating-related outboard engine failures. Trimming the outboard up too much while underway or in turns can cause the water pickups to ingest air – this causes a sudden loss of water pressure – not a good thing.

The most common cause of outboard motor overheating is water pump failure. Water pump failure can also be caused by a defective heat exchanger, though this is harder to check. Generally, if it is not a problem with lack of raw water flow or fresh water, the heat exchanger will be the cause.

Subsequently, question is, what would cause a boat to overheat? Overheating can also be caused by a worn or damaged water pump impeller. If the impeller is damaged and is missing a vane, make sure any displaced pieces are accounted for and removed. Any debris left in the water passages may reduce flow, which leads to persistent overheating.

Similarly, it is asked, how do you know if your outboard is overheating?

If it has a telltale, and there’s water coming out, it ain’t getting hot. If you stick your finger under the telltale water it should be warm, but not hot. If the motor has a thermostat, it will probably run a little hotter.

How does the cooling system work on an outboard motor?

An Outboard Cooling System. As gasoline is burned in an outboard motor, the temperature quickly rises in and around the piston and cylinder. The water comes into the outboard’s engine through the lower unit, which is below water level as the boat is moving.

How long can you run a boat motor out of water?

Run the engine for 10 minutes, or according to the manual’s instructions. If you’re flushing the motor, most manufacturers recommend running it for 5 to 10 minutes. If you’re running the engine for another purpose, such as to test its function, run it for as long as your maintenance task requires.

Does my outboard need a thermostat?

Yes, you can temporarily run your outboard without the thermostat and not harm the engine. Getting through the current problem and getting back on the water without harming your engine is the end goal to all boaters.

Does an outboard motor have a thermostat?

One of the least appreciated components of an outboard motor is the lowly thermostat. A thermostat regulates the temperature of the water for engine cooling and keeps pressure in the cooling system to facilitate heat transfer from the heads and the cylinder walls.

Will timing cause engine run hot?

If the ignition timing is incorrect, not only will the engine run too hot but it won�t have the power it should. An incorrect air/fuel mixture can also cause an overheating problem; a lean air/fuel mixture will cause an engine to create more heat than a rich air/fuel mixture.

How hot should outboard motor run?

The thermostat will usually run the engine somewhere around 135f at idle if operating properly. Have found through the years that the statement about holding your hand on it for about 3 seconds is usually correct. That’s usually around 135f!

Should I change thermostat when changing water pump?

Most of the time, RRT will recommend replacing the thermostat at the same time as the water pump. A thermostat is also essential to a properly running engine and it’s simple design is also it’s downfall because it can become gummed up or jammed.

What temp is too hot for an engine?

For most cars, the normal operating engine temperature is in a range of 195 to 220 degrees Fahrenheit, though most dashboard temperature gauges don’t show an exact temperature. Instead, there are typically markings for cold and hot on the edges of the gauge and a normal range in the middle.

How long does it take an engine to cool down?

30 minutes

Should boat motor be stored up or down?

Should I leave my engine up or down? Simply put, if you are leaving the boat in the water, leave it in the up position to avoid growth. If you are leaving it out of the water, trim it down to drain the water and protect the Power Tilt and Trim seals from the sun.

What causes a boat motor to lose power?

You most likely have a filter problem or fouled plugs. That could be why your boat motor is losing power. Prevention: It’s possible to buy a bad load of fuel, but it’s more likely that the fuel went bad while in your boat. Leaving a tank near empty for long periods of time can cause condensation and water in the gas.