fuel pump/dual tank explaination???
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From: CONCORD NC
fuel pump/dual tank explaination???
does anyone know how exactly the single fuel pump manages to keep the tanks balanced on the C5's. This is one part of the car I still haven't figured out.
Thanks!
Dave
Thanks!
Dave
Burning Brakes
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From: Annapolis, MD USA
Re: fuel pump/dual tank explaination??? (davidfarmer)
Dave - I have asked this question before, but never received an answer. The point of my question was "how do you keep more fuel in the right tank in order to keep the overall balance better."
I have to assume that there is a siphon-type arrangement between the tanks which keeps the tanks more or less equally filled. I also would like to know the definitive answer, and if there is a means of adjusting the balance between the tanks. Regards, Robert
I have to assume that there is a siphon-type arrangement between the tanks which keeps the tanks more or less equally filled. I also would like to know the definitive answer, and if there is a means of adjusting the balance between the tanks. Regards, Robert
Drifting
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From: San Francisco CA
Re: fuel pump/dual tank explaination??? (davidfarmer)
Excess fuel pump pressure is used to create a siphon jet in the crossover that draws fuel from the right tank to the left tank. When the left tank is full, excess fuel returns to the right tank through another crossover :cheers:
Burning Brakes
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From: Annapolis, MD USA
Re: fuel pump/dual tank explaination??? (SFVetteman)
Now that you mention it, I recall that the problem is that the left tank is kept full, while drawing from the right tank.
This is not an optimal setup for a car with the driver on the left.
This also may have something to do with the screwy fuel guage on these cars. The question remains - how would one go about keeping more fuel on the right, or even reversing the fuel tank bias left to right??
This is not an optimal setup for a car with the driver on the left.
This also may have something to do with the screwy fuel guage on these cars. The question remains - how would one go about keeping more fuel on the right, or even reversing the fuel tank bias left to right??
Melting Slicks
Joined: Jan 2001
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From: Aloha, Oregon
Re: fuel pump/dual tank explaination??? (SFVetteman)
Excess fuel pump pressure is used to create a siphon jet in the crossover that draws fuel from the right tank to the left tank. When the left tank is full, excess fuel returns to the right tank through another crossover :cheers:
robert judd
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From: CONCORD NC
Re: fuel pump/dual tank explaination??? (rwj383)
The ultimate question is this, I seem to be empying my driver (primary) tank without using all of the fuel from the passenger tank. Is there a way to increase the crossover rate, so that the driver tank stays full?????
At this point, balance is not nearly as big a problem as starvation.
Thanks!
Dave
At this point, balance is not nearly as big a problem as starvation.
Thanks!
Dave
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From: CONCORD NC
Re: fuel pump/dual tank explaination??? (MANNY)
I was under the impression the primary pump in the drivers' side tank, does both. There is no pump in the passenger side tank.
Other than replacing the OEM pump with a bigger unit from Lingenfelter, everything is stock.
The manual mentions a "jet pump", but I think that is an expression, and not an actual pump. If it is, please point me to it.
Dave :withstupid:
Other than replacing the OEM pump with a bigger unit from Lingenfelter, everything is stock.
The manual mentions a "jet pump", but I think that is an expression, and not an actual pump. If it is, please point me to it.
Dave :withstupid:
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Drifting
Joined: May 2002
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From: San Francisco CA
Re: fuel pump/dual tank explaination??? (davidfarmer)
Dave, perhaps an even bigger fuel pump would increase the transfer rate, if one is available.
Otherwise, the only solution I can think of to solve your problem is to plumb in another line from the right tank to the left with a small fuel pump to assist in the transfer.
Ideally, you would want the pump operation controlled by the float/fuel sensor in the right tank so that when the right tank is dry the pump would shut off.
Otherwise, the only solution I can think of to solve your problem is to plumb in another line from the right tank to the left with a small fuel pump to assist in the transfer.
Ideally, you would want the pump operation controlled by the float/fuel sensor in the right tank so that when the right tank is dry the pump would shut off.
Melting Slicks
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From: DFW TX
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Re: fuel pump/dual tank explaination??? (Godspeed)
Dave, I asked Lou about it and he recommended just tapping the lowest point on each tank and connecting it was an AN line. Gravity will balance out the tanks - he said he used to do that in his Mustang World Challenge car years ago.
Melting Slicks
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Re: fuel pump/dual tank explaination??? (MANNY)
don´t get why some "specialists" above figure out their own fuel-pump-setup-inventions and base an answer on imagination. What´s the point?
Drifting
Joined: May 2002
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From: San Francisco CA
Re: fuel pump/dual tank explaination??? (Godspeed)
I knew if I lived long enough I would eventually make a mistake :bb Manny is right :smash: I had thought from reading the manual that the jet pump was not a real electric pump, but such is not the case.
My parts book describes it as a fuel pump and it has an electrical harness associated with it as well. The part number of the pump for a 2001 is 88895126.
It is now apparent that the your problem is most likely a bad jet pump :banghead:
Thanks, Godspeed for posting that diagram as it gave me the idea to look in my parts book.
My parts book describes it as a fuel pump and it has an electrical harness associated with it as well. The part number of the pump for a 2001 is 88895126.
It is now apparent that the your problem is most likely a bad jet pump :banghead:
Thanks, Godspeed for posting that diagram as it gave me the idea to look in my parts book.
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From: CONCORD NC
Re: fuel pump/dual tank explaination??? (SFVetteman)
Apperantly, the jet pump is so small I never realized it actually was a pump. I will pull the right tank apart and ispect everything. Hopefully, I can manually run the pump and check it out. If it is working properly, I may rig the right side float so that it apears "empty" to the computer, just in case the pump is shutting down due to all of the cornering and "sloshing".
Thanks for all of the help!
Dave
Thanks for all of the help!
Dave
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From: CONCORD NC
Re: fuel pump/dual tank explaination??? (bowtiebandit)
I finally found it in the manual. It is indeed a venturi pump, not an electric pump. It uses a small amount of pressurized fuel from the main pump to pump fuel back to the left side. It seems like it would take more fuel to run the pump than it could pump back, if I remember my physics properly.
I am going to drain the tanks and look things over. I may buy a cheap electric pump to simply pump all fuel from right to left. I am starting to think that maybe, on certain tracks, the crossover jet pump simply cannot keep up. I get 3 miles to the gallon on track, and it may simply not be able to keep up.
Any spare parts are welcome!
David Farmer
2504 W Main Street
Albemarle NC 28001
I am going to drain the tanks and look things over. I may buy a cheap electric pump to simply pump all fuel from right to left. I am starting to think that maybe, on certain tracks, the crossover jet pump simply cannot keep up. I get 3 miles to the gallon on track, and it may simply not be able to keep up.
Any spare parts are welcome!
David Farmer
2504 W Main Street
Albemarle NC 28001
Drifting
Joined: May 2002
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From: San Francisco CA
Re: fuel pump/dual tank explaination??? (davidfarmer)
That's what I thought from reading the manual. However, what's a fuel pump harness doing in the right tank when there is no electrical pump? The part number for the harness is the same as the one in the left tank and the parts book calls it a fuel pump harness.
I'm sure when you get the right tank apart, you'll solve the mystery. Perhaps the harness while the same as the one in the left tank only uses the wires for the fuel sensor and the fuel pump wire is unused.
I'm sure when you get the right tank apart, you'll solve the mystery. Perhaps the harness while the same as the one in the left tank only uses the wires for the fuel sensor and the fuel pump wire is unused.
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Re: fuel pump/dual tank explaination??? (MANNY)
Well, it is in there, but I am basically convinced that the "jet" pump simply cannot move the fuel fast enough to keep up with my needs. I am going to block off the pressurized jet "feed", and add a dedicated electric return fuel pump to pump fuel back to the primary tank. Any overflow can easily pass back up and over the top crossover.
Eventually, I want to make the passenger tank the primary, and feed into and out of it. That would help with weight. However, the in-tank pump Won't fit properly (I tried), and I don't have time before Sears Point to switch pumps.
Thanks for all the help!
Dave
Eventually, I want to make the passenger tank the primary, and feed into and out of it. That would help with weight. However, the in-tank pump Won't fit properly (I tried), and I don't have time before Sears Point to switch pumps.
Thanks for all the help!
Dave
