What temperature should an inboard motor run at?
There are two common tstats – 140 degree and 160 degree. If you’re running normal you should see temps about 10 degrees above the tstat. You might have a 140 degree tstat in yours.
How does a MerCruiser thermostat work?
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. As the waxy mixture expands from water heating up, it pushes upward on the piston attached to the bottom of the thermostat valve.
Can you run a MerCruiser without a thermostat?
Can I Run My Outboard Without The Thermostat? Yes, you can temporarily run your outboard without the thermostat and not harm the engine. No, you can not remove the thermostat and continue running the engine for long periods of time without causing harm to the engine.
How many horsepower is a 350 MAG MerCruiser?
300-hp
The 350 MAG MerCruiser is called a 350 MAG and typically is rated at 300-hp. As you can see the engines are pretty much the same, except for the 15% difference in displacement and horsepower.
What temp should a Mercury outboard run at?
NORMAL idle temps should fall in the 120-140 degree range. Most commonly right around 125-132.
What temp should Mercruiser run at?
The “temp” gauge you are referring to on your dash should be reading somewhere between 160-180.
How do I know if my boat thermostat is bad?
Symptoms of a failed thermostat (open position)
- Engine slow to warm up.
- Engine not reaching its correct operating temperature.
- Poor cold weather performance.
- Water flowing from the exhaust pipe at idle.
How do I test my boat thermostat?
Step 2: Put the thermostat in a bowl and immerse it in boiling water. As the thermostat heats up, it should open. When you remove it from the boiling water, allow it to cool and it should close again. If the thermostat remains open or closed, it has failed and must be replaced.
How many hours will a MerCruiser 350 Mag last?
The 350 MAG with proper maintenance should last at least 2000 hours before it needs a major rebuild.
How much fuel does a 350 MerCruiser use?
| Select MerCruiser Test Model | HP | Fuel consumption WOT |
|---|---|---|
| MerCruiser 5.7 L – 350 cid | 260 hp | 21.0 GPH |
| MerCruiser 5.7 MAG – 350 cid | 300 hp | 23.0 GPH |
| MerCruiser 6.2 MAG – 377 cid | 320 hp | 24.5 GPH |
| MerCruiser 7.4 MPI – 454 cid | 310 hp | 28.5 GPH |
How do I know if my outboard thermostat is bad?
Why is my Mercury outboard overheating?
The most common cause of outboard motor overheating is water pump failure. Lack of fresh water can be noted if there is a large increase in temperature between the inlet and and outlet of the heat exchanger. Water pump failure can also be caused by a defective heat exchanger, though this is harder to check.