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His by pass system puts high pressure fuel back to the suction side of the fuel pump, also reducing the need for micro sized fits within the pump. Probably why a bigger bore fuel pump is required.Just my thoughts and observations from afar.Best RegardsBob
Bob, the bypass does go back to the inlet, but what I found was that it is at greater pressure than the incoming, so it tends to go to the tank as well. you may be right, in that the backflow takes care of the overvolume. Like my wife says to me at times," it can't be that hard to do"!!!! It bugs me that this is so difficult.
My mistake, it is 4mm....that is why I picked 3/16", come to think of it. I emailed him re my problems, and he said that he was having similar problems. He pulled the spring out of the injector. The only way he could get it to run "slow" was to restrict the inlet to 1/8" dia. I asked him if he heated it to start it, but there was no reply to that yet. He has a needle valve on the return line to adjust the fuel volume going to the injector. he said that it is too coarse and a small movement makes a too big change. said he was going to fiddle with the taper on the needle. I couldn't get that working at all, it was either too closed, or too open.
he was invited to got to the Detroit Diesel factory, and while there, he toured some of the manufacturing area'sHe was a big fan of Detroits and called them" Detroit drippah's "
Now 3x that tolerance is .0001" or 1 "tenth"....WE MIGHT be able to do that in a home shop....but I think it won't be easy, and we'll need to think about that for a bit Dave