 Fuel pump physics, Push/pull/suck/pump? |
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| lmcchesney |
 Feb 3 2004, 06:49 PM
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Member  Group: Members Posts: 488 Joined: 24-November 03 From: Ocala, Fl. Member No.: 1,381 Region Association: None  |
My little fuel pump(72) has been working for six years without a problem. Now that I am rebuilding the car and looked at the fuel hose diagram with fuel flows as per PP and DD, I must admit. I have not the foggest how this little pump works.
Fuel tank supply feeds a "Y" connector with the "R" port on the pump and the fuel line feeding the engine compartment. I do not see a valve in the "Y" connector. Fuel returns from the engine compartment to enter the "S" port. Then the "D"port returns the fuel to the tank. If the roller pump works by pushing fuel out the "R" port, why would the fuel not flow to the engine compartment and back to the tank via the supply line? I have done a search and reviewed the classic section without finidng the answers. What mechanism is being used? Thanks, L. McChesney lamcchesney@netzero.net |
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| lmcchesney |
Feb 8 2004, 07:30 PM
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Member Group: Members Posts: 488 Joined: 24-November 03 From: Ocala, Fl. Member No.: 1,381 Region Association: None |
I got the test run of the dual pump dual fuel runner circuit done and it looks great.
The engine is not in as yet so I hooked up the circuit and powered it directly from a 12V source. I triggered the injectors using a 3V battery supply. Adjusted the rale pressure to 40psi. Triggered a injector and pressure rock solid at 40psi. To review the system: Feed line 5/16 from the tank, through filter, split to two Bosch 0580463009 pumps in the front trunk. Two seperate (D)delivery lines via 5/16 metal fuel lines through center tunnel to engine firewall. Each fuel line via 5/16 hose to a fuel rale created from 3/8" brass fittings with 3/8 hose feeds to injectors and a "Tee" for pressure gauge and cold start. The rales are "Y"ed together to enter the single fuel regulator. The fuel regulator feeds a 5/16 return line through the center tunnel to front trunk. There return is split to the two pumps "R" and "T"ed to fuel tank. It took a couple minutes to get up to pressure and one injector leaked for a while but then stabilized. The spray cone from the injectors looks good. Have not measured flow yet, next project. Any advice on cleaning/rebuilding the injectors? Thanks all, L. McChesney |
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Posts in this topic
lmcchesney Fuel pump physics Feb 3 2004, 06:49 PM
Brad Roberts Um.. the Y is only used on the R side (return from... Feb 3 2004, 06:53 PM lmcchesney Brad, that is the way I understood the system as w... Feb 3 2004, 07:15 PM lmcchesney I think I have it now. The diagram confused me. ... Feb 3 2004, 07:21 PM Brad Roberts No problem.. when I come across some free time, I... Feb 4 2004, 01:12 AM Dave_Darling S = "Saugen" == German for "suction"
D = "Druck" =... Feb 4 2004, 10:51 AM lmcchesney Thanks Guys,
No complaints DD. Now a question tha... Feb 4 2004, 05:59 PM Dave_Darling 9mm feed line, 7mm return.
If you mean was I look... Feb 4 2004, 06:09 PM Racer Chris I like to think of S as "supply", D as "delivery",... Feb 4 2004, 09:18 PM lmcchesney Thanks all,
Chris, the duel pump is for stable pre... Feb 5 2004, 06:24 AM Racer Chris L.,
Twice the pumps equals twice the volume. Ther... Feb 5 2004, 07:15 AM
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