Bullmoose44 Posted October 27, 2012 Share Posted October 27, 2012 I have a 72 240Z with a L28 turbo fuel injected swap. I have been working on the body and interior for about 18 months and when I went to fire it up, I could not get the old rail mount fuel pump to fire at all. I checked all the wiring and determined that the pump was bad and I figured that it had set up since it had been ran in about 1 1/2 years. I ordered a new pump from Summit Racing and installed in the same location with a new inline filter between the tank and the pump. I fired it up and it ran fine as I started the car and just eased around for about 30 minutes to circulate all the fluids and check for leaks in the aluminum radiator. I backed it in the garage and the pump has not fired since. I thought it was just a wiring short so I ran a new hot wire from the relay to the pump and even changed out the relay. It never dawned on me that it would be the pump until I chacked the power at the pump and it was reading 12.1 volts across the terminals. So, it seems that the pump is bad and I am going to return it to Summit and they are going to exchange it. My question is did I get a bad pump or do I have something else that is damaging the pump? The previous one had ran for years before I tore the car apart so it is not location I don't think. I am using gthe same wiring setup and the same ECU so I can't think of any new variables that would damage it. What are you thoughts and experiences? I was also wondering what pressure you guys were running on EFI setups? Quote Link to comment Share on other sites More sharing options...
Domzs Posted October 27, 2012 Share Posted October 27, 2012 How you did test your pump wiring ? One should be 12 v and the other should be ground . If both wires show 12 v then you don't have ground . Quote Link to comment Share on other sites More sharing options...
tamo3 Posted October 27, 2012 Share Posted October 27, 2012 Did you replace entire fuel rail? I thought fuel injection require bigger diameter fuel pipe than carb. Quote Link to comment Share on other sites More sharing options...
Bullmoose44 Posted October 27, 2012 Author Share Posted October 27, 2012 I guess I was not clear. There is 12.1 on the hot side and the ground is solidly connected. The fuel rail is the same one that has been on the car and worked for years. The odd thing to me is that it started and ran fine, then just would not start back and the pump appears to be dead. It is a bear to change out because of where it is mounted so I want to be sure I do not have other problems before I go to the trouble of replacing it. I am wondering if I may have a partially blocked line from the tank tot he pump or something else that is stressing the pump to failure. Quote Link to comment Share on other sites More sharing options...
tamo3 Posted October 27, 2012 Share Posted October 27, 2012 Maybe installing fuel pressure regulator is one thing to check whether pump is bring enough fuel to engine. Since it's electrical fuel pump, do you hear pumping sound from the it when you turn ignition? Also, how old is your gas? I hard old gas is harder to start engine. Quote Link to comment Share on other sites More sharing options...
NewZed Posted October 27, 2012 Share Posted October 27, 2012 I guess I was not clear. There is 12.1 on the hot side and the ground is solidly connected. The fuel rail is the same one that has been on the car and worked for years. The odd thing to me is that it started and ran fine, then just would not start back and the pump appears to be dead. It is a bear to change out because of where it is mounted so I want to be sure I do not have other problems before I go to the trouble of replacing it. I am wondering if I may have a partially blocked line from the tank tot he pump or something else that is stressing the pump to failure. The part that's not clear is what you mean when you say the pump doesn't work. If the pump turns, then the problem is most likely not electrical. But you're theorizing, above, about blocked fuel lines which implies that the pump is turning but no fuel is flowing. In your first post you said that the pump hasn't "fired" since you parked the car. What does "fired" mean? You said that the ground is connected, but you didn't say that you confirmed it's actually grounded, electrically. If you have 12 volts at the positive terminal, take a separate jumper or piece of wire and make sure that the negative terminal is grounded back to the battery. If the pump doesn't turn, don't worry about blocked fuel lines. You'll have to listen to the pump to find out if the pump is turning, or measure the voltage drop across the terminals like Domzs suggested. Listening is easier. Quote Link to comment Share on other sites More sharing options...
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