Old fuel draining by jumping the fuel pymp

jacek

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Hello, i need to drain the 7 y o fuel from my rescued cobra. The fill neck smells like varnish. I read somewhere that a hot wire on the black and pink inertia switch wire will run the fuel pump. Is that correct? Is that safe for the fpcm or should, could i disconnect it first?
Thank you for your help!!!
 

jacek

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Perfect.Thank you. I'm replacing the rear bumper cover as well so it should be easy
 

jacek

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Unfortunately the pump did not budge. I unplugged the connector, checked ground and put the positive from battery to where the black and pink plugs in ( top right looking at the receptacle) and negative to the grey wire ( second from the left on the bottom row) ---silence.... anything else i could do or is the pump shot?
 
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jacek

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is there a pinout here for the fuel pump plug? The schematics online are a bit confusing...
 

52merc

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The Fuel pump module in the trunk is connector C451. Pin-3 (RD-BK) is power [+] to the fuel pump. Pin-10 (BN-PK) is negative [-] to the pump.

C451 pinout.png


I would just drop the tank even if the you can get the pump working. Just imagine what that old fuel will do to the pump.
 

jacek

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Thank you. That helps. There is a full service planned . For now I'm just trying to fire her up. 7 years with the timing cover off in the top booth, dragged from one storage yard to another, "adventures" along the way.. it's a miracle most parts are here, i was able to assemble everything with minimal hardware needed to be bought. But... everything is questionable : plugs, coil packs, injectors, fuel lines. I even saw a small leak from the diff...Fortunately beside the front engine cover everything else looks original, untouched. There is hope. Cylinder leak down results were stellar...
 
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jacek

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Here is a picture i found of the plug under the bumper going directly to the pump. Is this the correct pinout?
 

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FIREBALL

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Dropping the tank with more than a couple gallons can be tough, I found out the hard way. You cant normally siphon out with a hose but when I needed to drop my tank a second time to replace fuel pump, I used a 1/8 hard plastic line like the ones for an oil pressure gauge. I was able to get it past everything and into the tank. It took about 5 hours to siphon about 5 gallons out, but it was worth it. Dropping the tank when empty is easy. The first time I went with the costly highly recommended DeatschWerks pump and it failed almost immediately. Second time I went with a Bosch and it workes great. Also if you need a fuel pump (which would be highly recommended being the pump has been sitting in that old fuel) buy the complete assembly not just the pump, it will save much time and frustration.

You can find the Bosch fuel pump assembly #67170 on Amazon for $112
 
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jacek

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Thank you. I ordered a new pump and filter. I think the plug pinout in the picture above is reversed b/c the ground wire color ( as per the pinout above) is red and the hot wire color is brown/pink. Anyway, i tried both polarities but only got a click and spark. No sound of the pump running. It seems stuck. Since the pump seems shot i ordered a new one. By the fuel gage it only shows minimal fuel level so it think I'm ok dropping it.
 

FIREBALL

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If you havent dropped it yet, you might find out how difficult it is to get tank away from the filler tube, although it is possible to change out pump without completely removing the tank. The other thing is its sometimes very difficult to remove the fuel line from the tank nipple. There are write up's/post that cover all this. If you do remove the tank completely you will need a new rubber donut seal for the tank.
 

jacek

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youtube is my good companion. Not to mention my general car experience. Based on what you wrote I'm preparing for the battle ;-)
 

01yellercobra

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I've used WD40 on the filler neck and the fuel line disconnect to help break things loose.
 

jacek

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Thank you guys- that helps. Small tricks make big difference. I'm through 2 tank removal videos so far.
 

jacek

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Ok so the tank is out and the pump assembly out of the tank. Your suggestions and YouTube made it painless. Thank you. I attached some pictures of the fuel "varnish" from the tank and the state of the pump sock. Oh yes and there is a small hole (fuel leaking) in the corrugated fuel tube out of the pump. That probably affected the fuel pressure as well.....It was the right decision to replace it.
On another note: i blew out the old fuel from the lines. Then i proceeded to put some mix if choke cleaned and seafoam in the fuel injectors rails. I figured that will help with restoring the function of the injectors. The fuel pump is arriving mid week so I will have that mixture in the fuel injectors rails for a few days. I hope that won't damage anything. Pleas advise. Thanks again!!!
 

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jacek

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One more question: i found this piece on the bottom of the pump assembly bucket. Does it belong anywhere or is it just a bumper piece for the pump assembly?
 

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