QuestionQUESTION: Hello Roland, it's me again Paul with the 89 new Yorker. I changed the fuel pump and it ran perfectly over hundred mile distances without a problem. My wife came in and said it was running out of fuel and it it died in the driveway. We put a gallon of fuel in and I can hear the pump running, but no fuel is coming to the filter (I have removed the pipe and checked). The pump is from a junkyard and from a 1990 and it looks different (large cylinder with the pump encased, whereas the old unit was exposed and had what looked like a diaphragm on it. It had a different plug too) but i adapted it to make it fit. Any ideas at all or do I have to drop the tank again? - Thanks in advance -Paul
ANSWER: Hi Paul,
When you say that you can hear the fuel pump running do you mean for just a second after you put the key in the run position, or also while you are cranking it? If you aren't getting anything out of the fuel filter while you are cranking it, and you know that it is running (though it might be hard to hear it over the noise of the starter motor) then it would seem the case that the pump is no longer actually pumping fuel. You can turn the pump on without cranking the engine by jumping 12V from the battery to the + post of the spark coil (dark green/black wire connects to it), and that will verify that the pump is running. Do that and verify that you still aren't getting fuel from the filter outlet. Then let me know if you are indeed getting fuel. Then we can consider other possibilities than that the pump is not working.
Roland
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QUESTION: Hi Roland, I mean I can hear the pump running when i jump out the fuel pump relay. I have removed the hose which supplies fuel to the filter and there is no fuel at all. Could it be because the pump used is different and does not sit low enough in the tank or would that not make a difference ? - Thanks, as always - Paul
ANSWER: Hi Paul,
Is there any possibility that your tank is just too low on fuel as to be below the intake opening? Unless the old and new pumps were greatly different in length I can't attribute the problem to specifically its intake not sitting low enough. But if you ran the tank virtually out of gas that might cause a difficulty in drawing up (priming the pump?) gas I conjecture. I recall that some people have reported trouble when they ran out of fuel unless they put a couple of gallons back in.
Roland
PS: Thanks for the kind evaluation and accolade.
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QUESTION: I have put two and a half gallons in and it spits a little (very little) but no stream at all, I have removed the tank and pump (it seems to be okay) I have even tried sucking up gas from the fuel hose in the engine compartment to no avail. Is there any particular way to prime the pump as my wife said she had a Plymouth minivan which burnt out a fuel pump when it ran dry. - thanks - Paul
AnswerHi Paul,
You might take a look inside the tank thru the pump mounting opening as there is said, in my '89 manual, to be a 'reservoir' within the tank into which returned fuel from the pressure regulator return line to the tank is dumped. The reservoir, into which the pump intake is positioned (sort of a tank within the tank) thus will get a fuel supply even though the fuel in the tank is running low. That reservoir needs to be filled in order for the pump to have anything to draw upon. If the the depth of gas in the tank overall is lower than the walls on the reservoir and the reservoir too is dry, then it won't pump gas even though there is some gas in the tank. Also if the tank isn't level in its "dropped" configuration, that too might explain why the reservoir isn't full. So that to me sounds like a possibility to check and is a 'pump prime' sort of concept. If you saved the old pump you might compare the depth of the intake tube of it to the used pump you subsequently installed
I don't know how much gas has to be in the tank for it to overflow the sidewalls of the reservoir and fill it, but maybe you still don't have enough depth to refill the reservoir.
That is about all I can see that might be relevant to your situation.
Roland
