Pumps & Dumps
Let's start with the foundation of a good hydraulic setup, the pumps.
A pump is exactly what you think it is. It pumps fluid from one place to another. Real simple really. You can equate it to a compressor in an airbag setup if it makes it clearer to understand. Here's how the pump works.
On one end of the pump is a 12 volt motor. That motor has a splined end on it, and the motor bolts to what is called the block. The block is a 6X6X1 piece of aluminum that is milled to accept fittings and so on.
At the other end of the block is the gear. The gear has a splined end on it also. The two splined ends, one from the motor and one from the gear, are connected by what's called a key. This key can come in many different spline patterns so that you can change motors without having to change gears.
Surrounding the gear is a tank. The tank itself is a reservoir for hydraulic fluid. It serves to provide fluid to the gear when the gear turns, as well as to catch the returned fluid when it is expelled from the system.
So how does it work? If you give the motor 12v of power, it turns the splined end. That splined end turns the key, which turns the gear. The gear itself has two gears inside of it which suck the fluid from the tank into the gear, and pulls it through passageways in the block, out to the port at the top known as the "press" or pressure fitting.
Dumps
After the pressure fitting, there has to be a way to divert where the fluid goes. In an airbag system, they're known as valves. Hydraulic systems have valves too, they're called Dump Valves, or dumps for short. On the inside, a dump is shaped like a "T". Fluid can pass through the top of the "T" all day long without any problems. The bottom of the "T" is controlled by the valve itself. When power is given to the dump, the stem of the dump opens, which releases pressure and allows the fluid through the bottom of the "T'. The fluid then goes through a hose called a return line, and then into a slow down valve. All a slow down valve does is control the flow of fluid to the tank. It's a needle valve, so you turn a screw to speed up or slow down the fluid. Since the truck is dropping only as fast as the fluid can move, the slow down is essential to keep the truck from "gravity dropping." The slow down is the ported into the block, which dumps the fluid back into the tank, recycling the fluid and resetting things to normal. The slowdown gives hydraulics a distinct advantage over airbags, as you can now control how your truck drops, even how fast each corner drops, depending on how your slowdowns are installed. I've seen plenty of bag setups that drop by gravity, and that can't be good.
There is one other piece that goes between the press and the dump, and that's the check valve. Just like any other check valve, it keeps fluid moving one direction, and doesn't allow it to go back. Hydraulics work on pressure, and the check valve allows the pump to build up pressure. Without it, the truck would fall right back down once the truck had been lifted.
Let's start with the foundation of a good hydraulic setup, the pumps.
A pump is exactly what you think it is. It pumps fluid from one place to another. Real simple really. You can equate it to a compressor in an airbag setup if it makes it clearer to understand. Here's how the pump works.
On one end of the pump is a 12 volt motor. That motor has a splined end on it, and the motor bolts to what is called the block. The block is a 6X6X1 piece of aluminum that is milled to accept fittings and so on.
At the other end of the block is the gear. The gear has a splined end on it also. The two splined ends, one from the motor and one from the gear, are connected by what's called a key. This key can come in many different spline patterns so that you can change motors without having to change gears.
Surrounding the gear is a tank. The tank itself is a reservoir for hydraulic fluid. It serves to provide fluid to the gear when the gear turns, as well as to catch the returned fluid when it is expelled from the system.
So how does it work? If you give the motor 12v of power, it turns the splined end. That splined end turns the key, which turns the gear. The gear itself has two gears inside of it which suck the fluid from the tank into the gear, and pulls it through passageways in the block, out to the port at the top known as the "press" or pressure fitting.
Dumps
After the pressure fitting, there has to be a way to divert where the fluid goes. In an airbag system, they're known as valves. Hydraulic systems have valves too, they're called Dump Valves, or dumps for short. On the inside, a dump is shaped like a "T". Fluid can pass through the top of the "T" all day long without any problems. The bottom of the "T" is controlled by the valve itself. When power is given to the dump, the stem of the dump opens, which releases pressure and allows the fluid through the bottom of the "T'. The fluid then goes through a hose called a return line, and then into a slow down valve. All a slow down valve does is control the flow of fluid to the tank. It's a needle valve, so you turn a screw to speed up or slow down the fluid. Since the truck is dropping only as fast as the fluid can move, the slow down is essential to keep the truck from "gravity dropping." The slow down is the ported into the block, which dumps the fluid back into the tank, recycling the fluid and resetting things to normal. The slowdown gives hydraulics a distinct advantage over airbags, as you can now control how your truck drops, even how fast each corner drops, depending on how your slowdowns are installed. I've seen plenty of bag setups that drop by gravity, and that can't be good.
There is one other piece that goes between the press and the dump, and that's the check valve. Just like any other check valve, it keeps fluid moving one direction, and doesn't allow it to go back. Hydraulics work on pressure, and the check valve allows the pump to build up pressure. Without it, the truck would fall right back down once the truck had been lifted.