Fuel Pump
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August 2016

Recently the car developed the bad habit of dying unexpectedly while driving. After dealing with other problems I finally had the opportunity to pull the Sending Unit/Fuel Pump assembly from the gas tank. This revealed a very badly charred bulkhead connector. The particular connector pin that had disintegrated was the +12 volt feed for the fuel pump. Why did the 12 volt supply pin char and disintegrate? I can only guess. But the fuel pump seemed to be operational and wasn't drawing more current than it should so I chose to repair the wiring and re-use the fuel pump.

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The sending unit is a non-serviceable assembly. Having to replace the entire sending unit because of a charred bulkhead connector seemed like a bad idea. So, I asked the members of the CorvetteForum.com for advice and as usual they came through. They sent me to RaceTronix.com for the electrical components I'd need to repair the wiring.

I purchased a BCWA-C43 Bulkhead Wiring Assembly and cannibalized the supplied harness to graft it into the original fuel pump wiring. I used some metal barrels that I removed from some crimp connectors to solder the old and new wires together in a butt-splice configuration. Removing the plastic sleeves from the metal barrels is necessary because the plastic sleeves won't hold up well when exposed to gasoline.

I staggered the metal barrel splices to keep them from touching each other. The in-tank wiring is Teflon coated and very stiff. With the wires routed properly and the splices staggered they are unlikely to move around and so I'm not concerned with short-circuits.

The only questionable part of this repair was the loss of the white plastic box attached just under the original bulkhead connector. I haven't found any definitive answer as to what it is and what purpose it serves. Some have said it is a capacitor but I spent some time picking the thing apart and found what looked like two choke coils embedded in the plastic. But I can't say this with any certainty since the parts are potted and were pretty much destroyed in the process of trying to expose them. Only the engineers at General Motors know for sure what this thing is and they aren't talking.

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