How to bypass the fuel pump on the carburetor?
How to bypass the fuel pump on the carburetor?
Onan B48M 18 HP – Bypass the fuel pump on the carburetor? I have been working on a ’78 Onan B48M opposed twin cylinder engine. The engine runs fine when I pour gas down the carburetor. However, when I feed gas through the fuel line, it leaks out the bottom of the fuel pump, which is connected directly on the carburetor.
Do you need a bypass regulator for an EFI fuel pump?
Because an EFI fuel pump can produce a large amount of flow, a bypass regulator is necessary in order to return the excess fuel back to the fuel tank. When shopping for a bypass regulator make sure that you buy one that is specific for carbureted applications. This is because most carburetors only require around 6 psi to operate.
Can a EFI fuel pump support a carbureted engine?
Keep in mind that since the pressure requirements of a carbureted application is lower that an EFI application the flow rate of your pump will be higher. This means that the fuel pump is capable of supporting higher horsepower.
What kind of fuel pump does Onan b48m use?
With time the seals in the pump tend to dry out. Don’t know which carb and fuel pump you now have, because you did not give us your spec number. Most of the older Onan engines came with a Marvel Schebler carb. I have seen this engine with a Marvel Schebler carb with mounted pump with both three and four hoses.
Onan B48M 18 HP – Bypass the fuel pump on the carburetor? I have been working on a ’78 Onan B48M opposed twin cylinder engine. The engine runs fine when I pour gas down the carburetor. However, when I feed gas through the fuel line, it leaks out the bottom of the fuel pump, which is connected directly on the carburetor.
With time the seals in the pump tend to dry out. Don’t know which carb and fuel pump you now have, because you did not give us your spec number. Most of the older Onan engines came with a Marvel Schebler carb. I have seen this engine with a Marvel Schebler carb with mounted pump with both three and four hoses.
Do you need a carb mounted fuel pump?
Carb kits are not that expensive and if you have an electric pump, they are reasonable also. If you have a carb mounted pump, we will need to know which style, because if it is part of the carb, with no visible fuel outlet, you will need to rebuild or replace the pump, even if you try to convert to a gravity system.
