Hot fuel pump connector

April 29, 2012, 08:57:00 PM

1984 5.0L Thunderbird

I switched the dual pump system to a single in-tank 255 lph pump. I gave it a hefty (12 gauge) new ground wire, just to be safe. Everything seemed fine for a very long time (6 months or more).

Now the ground pin on the fuel pump connector (outisde of pump hanger to harness) gets so hot that it cracks open the plastic connector. It's the only spot it the pump wiring that gets hot. I put a thermocouple to it while it ran and it was getting upwards of 130°F after about 2 minutes of operation.

Everything's been checked by myself and family members who are also mechanically inclined. I would suspect a bad contact, but I've checked that and even put some dielectric grease in there to really make sure the contact is good. The pump itself is only pulling 7.7 amps, which doesn't seem like enough to cause this much heat.

Has this ever happened to anyone else? Is it "normal"?

Hot fuel pump connector

Reply #1 – April 29, 2012, 09:51:28 PM

Did you solder the connection???? Post a photo of the issue at hand. I have dual pumps with no issues. Dielectric compound is an insulator you know. Many connector manufacturers do not recommend using it. We had a huge issue with the compound on ABS systems a year ago. First they told us to use it then they changed their minds. If the connector is hot it has a poor connection. Drawing 7.7 amps is high but it should not get hot. Post the connection just so we know we are on the same page.

Note are you talking about the plastic sleeve on a crimp connector getting hot and cracking. I am going to assume it is the outside ground eyelet terminal you speak of. If so you have a resistive connection that needs looking after and you should always crimp and solder high load connections. I personally do not trust crimp connectors. They suck. I use plain crimp connectors solder and shrink tubing for a permanent job. And make sure you use a star washer and grind the ground point to bare metal before tightening the nut and bolt down. post a photo just so we can see the issue at hand.