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Discussion Starter #1
My fuel pump will not switch on,The relay clicks on but no power to pump, I supplied 12 Volts direct from battery and the pump works, But will i burn it since it pumps all the time, What other electric component is major player besides the fuel pump please? The model is SEL 500 1983 model
 

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My fuel pump will not switch on,The relay clicks on but no power to pump, I supplied 12 Volts direct from battery and the pump works, But will i burn it since it pumps all the time, What other electric component is major player besides the fuel pump please? The model is SEL 500 1983 model
1. The fuel pump is intended to run non-stop when the car is running.
2. Usually the cause of FPR failure is just bad solder joints at the connector of the relay. Dissassemble it and solder those. You may have your relay working again.
3. Fuel pump relays are cheap on ebay. AFAIK, the relay is the same for 1982 to 1984 M116/M117 V8 engines. Euro versions cut at 5850 rpm, US versions at 5500 rpm, but that's just nitpicking, you can use either.
4. Search the forum before you get Teutoned.
 

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To check if the FPR is the problem you can jumper the appropriate pins and see if the pumps run that way. If they do, FRP is the problem. If not, you have another problem.
 

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1. The fuel pump is intended to run non-stop when the car is running.
2. Usually the cause of FPR failure is just bad solder joints at the connector of the relay. Dissassemble it and solder those. You may have your relay working again.
3. Fuel pump relays are cheap on ebay. AFAIK, the relay is the same for 1982 to 1984 M116/M117 V8 engines. Euro versions cut at 5850 rpm, US versions at 5500 rpm, but that's just nitpicking, you can use either.
4. Search the forum before you get Teutoned.
I heard that Flavio.
Actually of the three Euro FPR I have, two are marked 5950 rpm, and another has an adjustment knob, and is marked 6000 rpm.
 

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I heard that Flavio.
Actually of the three Euro FPR I have, two are marked 5950 rpm, and another has an adjustment knob, and is marked 6000 rpm.
Actually, both of the FPRs i've seen, have two internal potentiometers inside. I BET they are for adjusting (a) the kickdown cancelling RPM and (b) the fuel cut-off RPM. I don't have a signal generator and oscilloscope at hand so i chose not to tinker with those.
 

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Discussion Starter #7
fuel pump wiring diagram

Is there anyway to have complete fuel pump circuit?As to know which pins goes to where?
 

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Time to get re-Tuetoned. Do a search. It has been covered approximately 6.23541 billion times. Jump pins 7&8 in the relay socket. That will send power to the pump. If the pump runs, do what flavio said in his first post of this thread.

Flavio, let us know if you figure anything out about the potentiometers. would be nice to be able to adjust the relays. thanks
 

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Discussion Starter #10
Ok

I found the pins ,pump is Ok ,Is there way to repair the relay or or check if power is supying the relay?
 

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I assume you got the car started by jumping the "pins", which I guess if you think about it is badly named, since they aren't the pins on the relay, rather the "socket holes" that thee pins plug into. Anyhow, with a wire between those two "holes", did the car start and run? If so, the problem is simply the relay and the wiring is fine and you are getting power, etc. You might be able to take apart the FPR and try resodering the insides, but not sure how easy or hard that is to do. Probably easier to get a good FPR and be done with it.
 
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