General background - for "interest"
I have just rebuilt my fuel pump, as the diaphragm was on its last legs and little or no fuel was making its way to the carb. The rebuild included new diaphragm and new one-way valves. Having installed it, I tested it, and there was a healthy amount of fuel going down the line. I connected it up to the carb using the existing pipework - i.e., nylon pipe, connecting with a short piece of rubber hose, connecting to a short piece of clear hose, connecting with another short piece of rubber hose which connected to the carb. I think the middle clear hose probably was a replacement for an in-line filter.
As this leaked, I temporarily replaced most of this i.e., from the nylon to the carb with a single modern piece of fuel pipe, with some nice new fuel line clips.
When I started the engine, fuel spurted out of the various "new" joins, and I had to sort these out one-by-one (insert in the nylon pipe, tighter clip all round etc)
Question:
What is the mechanism in the fuel pump that allows it to cope it wanting to send more fuel than the carb wants?
i.e., It is clear that the pump is now sending fuel at a very good pressure. As the carb is only taking the fuel it needs, what happens to the "excess" fuel, does this damage the one-way valves?
I have just rebuilt my fuel pump, as the diaphragm was on its last legs and little or no fuel was making its way to the carb. The rebuild included new diaphragm and new one-way valves. Having installed it, I tested it, and there was a healthy amount of fuel going down the line. I connected it up to the carb using the existing pipework - i.e., nylon pipe, connecting with a short piece of rubber hose, connecting to a short piece of clear hose, connecting with another short piece of rubber hose which connected to the carb. I think the middle clear hose probably was a replacement for an in-line filter.
As this leaked, I temporarily replaced most of this i.e., from the nylon to the carb with a single modern piece of fuel pipe, with some nice new fuel line clips.
When I started the engine, fuel spurted out of the various "new" joins, and I had to sort these out one-by-one (insert in the nylon pipe, tighter clip all round etc)
Question:
What is the mechanism in the fuel pump that allows it to cope it wanting to send more fuel than the carb wants?
i.e., It is clear that the pump is now sending fuel at a very good pressure. As the carb is only taking the fuel it needs, what happens to the "excess" fuel, does this damage the one-way valves?
