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Suspecting fuel pump

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Old Mar 15, 2010 | 03:37 PM
  #1  
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photocliff
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Default Suspecting fuel pump

Hi, I probably know the answer already but I thought I would look for some input from others on this.
The engine (69-302) not starting and no fuel squirts out into the carb when manualy pushing the throtle lever. I took the fuel line off behind the filter and cranked engine and no fuel still. At least I know it's not the filter. I placed my finger over the hose end and cranked the engine and all I felt was a faint puff of air coming out and then right after I felt a vacume pulling back into the hose. I thought that there could be blockage in the tank but the sending unit is new and the car has not been driven out on the streets, except out front in the house . I haven't burned a full 5 gallons just letting it run in the driveway and out front.

So my diagnosis came to a conclusion of the bad, new, fuel pump.

Thanks
Old Mar 15, 2010 | 03:41 PM
  #2  
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kalli
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well are you sure that you didn't run out of fuel? are you sure the fuelpump is not connected the wrong way round (inlet/outlet)?
Old Mar 15, 2010 | 03:51 PM
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if you feel a puff of air...it kinda sounds like its working..could have further issues than a diaphragm such as check valve or something like that.

I would poke around a bit more and make sure there is fuel in the tank.

-Gun
Old Mar 15, 2010 | 03:51 PM
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photocliff
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Ya, I poured 4.5 gallons of fuel into it last week. I intentionally ran it out of gas last fall. I didn't want it in the tank over the winter time. I even tried several times pouring fuel down into the carb just to get the motor working so that the pump would work faster.

Thanks Kallie. Sorry about your breakdown away from home.
Old Mar 15, 2010 | 03:53 PM
  #5  
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photocliff
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You can't reverse connect a mechanical fuel pump. It has two different fittings
Old Mar 15, 2010 | 03:58 PM
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Gun Jam
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And you are sure the 4 gallons didnt magically disappear???

You could try forcing air down the "In" line that heads to the tank and see if it flows well into the tank (remove gas cap then try it...can you hear bubbles or air venting) or see if fuel drains out of that line as well (depending on how the car sits)

If you get flow out of the "in" line then the fuel pump is the next in line so change it then.

-Gun
Old Mar 15, 2010 | 04:01 PM
  #7  
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Gun Jam
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Originally Posted by photocliff
You can't reverse connect a mechanical fuel pump. It has two different fittings
whats to stop you from putting the hose from the tank to the "out" line and the line from the carb to the "in " line?

Mine don't have no fitting just a brass tube that you jam 1/4" lines onto...any 1/4" line would fit either of those fittings on my fuel pump.

-Gun
Old Mar 15, 2010 | 04:15 PM
  #8  
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photocliff
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My pump has a 1/4 inlet for hose connection and a threaded outlet to carb.
I have had it running for the past two sumers and nothing has changed.

I will try the blowing air. That way I may know if it's not a clogged line.
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