Fuel pump help, Please |
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Fuel pump help, Please |
gster |
May 19 2018, 02:55 PM
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#1
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Newbie Group: Members Posts: 11 Joined: 15-April 17 From: canada Member No.: 21,021 Region Association: Canada |
I've installed an Airtex pump on the car as recommended by many.
The car does run but terribly.... I hope I've installed correctly and put the "T" adapter in the right place. The fuel line from the tank goes to the filter then to the pump. The pump output line is then T-eed to the other 2 lines.... Have I got this wrong? Is the filter restricting flow? The car has been sitting awhile and I've put fresh gas in. Otherwise nothing has changed. Any help is appreciated. |
jcd914 |
May 19 2018, 08:14 PM
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#2
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
The Fuel pressure regulator in the engine compartment dumps fuel to the fuel return line back to the tank. The 3 port fuel pump also has a pressure relief valve that can dump fuel to the return line to the tank. The return line from the fuel pressure regulator and the pressure relief valve on the pump are "T"d together near the pump.
If you replace the 3 port pump with a 2 port pump you eliminate the "T" fitting and the old line from the pump to the "T". The return line from the pressure regulator goes straight to the fuel tank. You should also be sure you are using fuel line rated for Fuel Inject pressure and the ethanol our gas has these days, J30R9 rating I believe. I have not seen any cloth braided fuel line that is rated for I pressure. Jim |
gster |
May 20 2018, 07:18 AM
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#3
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Newbie Group: Members Posts: 11 Joined: 15-April 17 From: canada Member No.: 21,021 Region Association: Canada |
The Fuel pressure regulator in the engine compartment dumps fuel to the fuel return line back to the tank. The 3 port fuel pump also has a pressure relief valve that can dump fuel to the return line to the tank. The return line from the fuel pressure regulator and the pressure relief valve on the pump are "T"d together near the pump. If you replace the 3 port pump with a 2 port pump you eliminate the "T" fitting and the old line from the pump to the "T". The return line from the pressure regulator goes straight to the fuel tank. You should also be sure you are using fuel line rated for Fuel Inject pressure and the ethanol our gas has these days, J30R9 rating I believe. I have not seen any cloth braided fuel line that is rated for I pressure. Jim Thanks to all for the advice. I thought about it last night ... I've re routed the fuel return line (from engine) back to the pump input ahead of the filter. Seems to run good and no leaks! Took it out for some fresh gas and air in the tires and all seems good. |
SirAndy |
May 20 2018, 11:26 AM
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#4
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Resident German Group: Admin Posts: 41,633 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
I've re routed the fuel return line (from engine) back to the pump input ahead of the filter. No! Do you still have fuel injection or do you have carbs? If you still have FI and you switched to a 2-port pump, the return line will go from your pressure regulator (the last part in the fuel system on your engine) straight back to the second nipple on the tank. That way the system can bleed off excess pressure and pump the not needed fuel back into the tank. Again, if this is still FI, you are also using the wrong hose and hose clamps, the whole system after the pump is under a lot of pressure and using the wrong components is a good way to burn your car to the ground. (IMG:style_emoticons/default/shades.gif) |
Mark Henry |
May 20 2018, 11:40 AM
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#5
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
I've re routed the fuel return line (from engine) back to the pump input ahead of the filter. No! Do you still have fuel injection or do you have carbs? If you still have FI and you switched to a 2-port pump, the return line will go from your pressure regulator (the last part in the fuel system on your engine) straight back to the second nipple on the tank. That way the system can bleed off excess pressure and pump the not needed fuel back into the tank. Again, if this is still FI, you are also using the wrong hose and hose clamps, the whole system after the pump is under a lot of pressure and using the wrong components is a good way to burn your car to the ground. (IMG:style_emoticons/default/shades.gif) (IMG:style_emoticons/default/agree.gif) Outlet of tank, inlet of filter, outlet of filter, inlet of pump, outlet of pump, back to engine's FI loop, in/out pressure regulator and back to inlet of tank. High pressure FI pump That's it. Carbs only need one line. Outlet of tank, inlet of filter, outlet of filter, inlet of pump, outlet of pump, to engine, here there can be a T fitting to feed the two carbs. Low pressure fuel pump and some use a low pressure regulator used before the carbs. Plug the FI return line. Exception, the PMO regulator for carbs does do a return to tank from the regulator. High (Stock) or low pressure pump can be used, PMO regulator only and a return must be used if using the high pressure pump. |
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