- 1 Which fuel line goes to the primer bulb?
- 2 Which fuel line is the return line?
- 3 Why do Weedeaters have 2 fuel lines?
- 4 Can I bypass the primer bulb?
- 5 What lines connect the engine to the fuel tank?
- 6 Can a fuel return line be too big?
- 7 Do you have to have a return fuel line?
- 8 How much pressure is in a fuel return line?
- 9 What are the two hoses on a carburetor?
- 10 How do you seal threaded fuel lines?
- 11 How do you put fuel back in a carburetor?
Which fuel line goes to the primer bulb?
The (clear) fuel intake line runs from the top of the carburetor (straight nipple) and goes to the short post on the back of the primer bulb. The return line (blue) comes from the long post on the back of the primer bulb and goes into the bottom of the fuel tank.
Which fuel line is the return line?
The vapour-return line normally runs from the fuel pump or the fuel filter to the fuel tank. This vapour-return line is connected to a special outlet in the fuel pump. Any vapour that forms in the fuel pump returns to the fuel tank through this line.
Why do Weedeaters have 2 fuel lines?
The supply lines need to connect to the fuel tank so that, when the weed eater is held in the operating position, they are below the fuel level. The vent and return lines will typically attach higher up. The lower line on the carburetor should be the supply line, the upper one would be above fuel to vent air.
Can I bypass the primer bulb?
No, it won’t work depending on the engine design. Without going into details the primer bulb forces fuel to the carb jets and not the engine directly. It also forces pressure and vacuum. Without the bulb your carb will be flooded on a permanent basis.
What lines connect the engine to the fuel tank?
The fuel line typically consists of rigid metal pipes, with flexible rubber or plastic hoses running from the pipes to the tank and the fuel pump, and from the pump to the carburettor. The flexibility of the hoses allows some movement between these different components.
Can a fuel return line be too big?
The return line has to flow enough not to create a back pressure on the regulator. This will effect fuel flow and pressure on the rail side. You cannot go to big.
Do you have to have a return fuel line?
You don’t need it with a mechanical pump. Mechanical pumps supply fuel based on RPM, and so long as you’re not running a big hipo mechanical pump, you’re fine without a return.
How much pressure is in a fuel return line?
around 40 PSI in an EFI system, though it could be higher or lower depending upon the application. The return line should only have residual pressure on ita PSI or two caused by the reistance of the fuel line to flow.
What are the two hoses on a carburetor?
The two hoses circled in red are vent/over flow hoses. Should not have any plugs in them. They basically both route between the two carbs, hanging down. Each carb has a vacuum nipple.
How do you seal threaded fuel lines?
Liquid or paste type sealant won’t clog. For gasoline, regular old gasoline resistant Aviation Form-a-gasket Number 3 is the best option. Another product also offered by Permatex is the High Temperature Thread Sealant.
How do you put fuel back in a carburetor?
Priming the Fuel Pump
- Disconnect the hose that connects the fuel pump to the carburetor.
- Spray a three second burst of starting fluid into the carburetor.
- Repeat the spray-and-die procedure until you see fuel begin to wet the rag on the fuel line.
- Reconnect the fuel line to the carburetor.