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Changing to Neg Ground - Fuel Pump?

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Dave, so can I just swap out the diodes (remove the bad old one on the car and replace it with the new one that hasn't been used)?

Thanks!
 
BrandonBJ8 said:
It still works now that I've changed to negative ground, but I think I'll just swap the diodes out and put the new diode on the car. That should hopefully prevent any disasters down the road! Thanks everyone for their input on this thread!
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The diodes in that pump are blown thats why it will work on either polarity. Don't try to swap the diode from the good pump to the one in the car unless you are a very good solderer.Removing the Diode's connector at the power post is not a cake walk. Swap out the good pump for the one in the car and fix the old one on the bench---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/hammer.gif
 
Yes you can. Just verify the diodes condition & polarity as ED said. If you need to, you can get a new diode from Moss - OR - I have just used garden variety diodes from radio shack. Something like a two amp at 100 piv rating. The end of the diode that has the stripe around it corresponds to the cathode end. Just clip out the old red & white diode wires at the lugs & solder the new diode to the lugs.
D
PS - I must be a good solderer. /bcforum/images/%%GRAEMLIN_URL%%/angel.gif
 
Hi Dave, Yes you can solder a garden variety diode in place. However, it may not be common knowledge that the little black component, in these pumps, we refer to as a diode also includes a swamping resistor. This resistor helps limit the current level generated by the back emf.--Keoke
 
Hi Keoke,
I didn't know about the swamping resistor. In any event, I've used a diode successfully for many years with no apparent problems. Maybe the replacement diode is stout enough to handle the current without a resistor?
D
 
I realy do not know Dave. But it just might be that a diode with a high PIV may also include additional forward resistance.---Keoke-?
 
I think I'll take the route of less soldering and just swap out the fuel pumps all together. I'll do that (probably next weekend) and hopefully everything will work out. Thanks everyone!
 
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