What does the poppet valve do on a Mercury outboard?
A poppit or poppet (sp?) valve is sort of a water-pressure regulator for the cooling system on an outboard engine. At slow rpm’s the pressure from the water pump is pretty low, so the poppit stays closed, and allows all the cooling water from the impeller to circulate thru the engine cooling system.
How does a poppet valve work?
A poppet valve consists of an orifice that is opened and closed by raising and lowering a sealing surface onto the orifice. It usually has an internal spring that holds the valve in the closed position. When the spring force is overcome, the sealing surface lifts off the orifice and the valve opens.
How do you know if your outboard is overheating?
How To Tell If Your Boat Is Overheating
- The first and easiest is if the dash gauge for the temperature goes out of the green and into red.
- If it feels like the engine is losing power, you might be overheating.
- An overheated engine may not want to start up again after you shut it off, until it cools down.
What type of valve is a poppet valve?
directional control valves
Poppet valves are often associated with pressure control equipment and applications. They are directional control valves and are typically characterised as being high flow, fast acting valves. This is due to the large flow paths through the main body of the valve.
How does a diaphragm valve work?
Diaphragm valves use a flexible diaphragm connected to a compressor by a stud which is molded into the diaphragm. Instead of pinching the liner closed to provide shut-off, the diaphragm is pushed into contact with the bottom of the valve body to provide shut-off.
How does an outboard motor cooling system work?
Most newer marine engines use an enclosed cooling system. This means that there is a small tank on the top of the engine that uses a combination of fresh water and coolant. This fresh water is circulated through the engine and through a heat exchanger. The fresh water, in this system, absorbs the heat of the engine.
What happens when 2 stroke outboard overheats?
When a 2-stroke engine is overheating, something within the system is in a bind. It may be physical bind such as gears grinding from inadequate lubrication or something less tangible like a clogged air filter. But something is causing the engine to run harder than it is designed to run.