When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I had both of my fuel pumps on my plow truck not working the other day. The truck is a 1987 Ford F250 4x4 with a 5.0 V8. The one in tank was just replaced. I checked the front pump by putting hooking it directly to a battery and it worked. So we checked all the usual things, like inertia switch, relays, and all that. Now, it was like -15*C with the wind chill here and we had to go plowing the next day. So we HAD to get this truck on the road. We hooked a wire from the front pump to the relay wires so that when the key is turned forward the pumps will work. This worked and we have gone plowing with no problems at all. Now can this be left like this or should I get this fixed ASAP? I am probably gonna look at it in the spring and was thinking a wire is probably broken somewhere. But it seemed like this problem was giving me signs because I would be driving down the road and it would kinda bog out then go again. It would only do it for like 1 second though. Mmm...the more I write this the more I think it should be in a different forum....oh well...someone will move it if needed! If you can think of anything let me know.
Depending on where you have the jumper wire hooked, is going to determine how risky running that way will be.
If you have it hooked to the proper output wire coming out of the relay, then you are only skipping the inertia switch. This switch turns the fuel pump off in case of an accident, where if you ruptured a fuel line, the fuel pump would cut off, instead of pumping fuel all over the accident scene. I would run it myself like this, but it's totally up to you.
If you have bypassed the relay all together, and are feeding it from somewhere else, then you may have circuit load problems, and also the computer will not have control over the pump like it does with the relay. Do what you have to do, but this is getting into more of a gray area as far as running it long term.