Fuel Pump Hammer Smack

On 9/17/2025 at 2:04 PM, chaseincats said:

The gas in my tank is probably ~6 months old at this point and the car had been sitting for around 2 months (without fuel stabilizer in the tank) while I am redoing its interior.

I was traveling a lot for work and when I returned and tried to start the car, the battery was dead. After charging it, I found that the car wasn't starting and traced it to the fuel pump. After a lot of poking and prodding with the test light I found that the wires to and from the pump were getting pretty hot so I gave the pump a few smacks with a hammer, as some orange gas was starting to sneak its way out around the hose (not a great color for gas), and it started right up and I let it idle for ~20 minutes while I added fuel stabilizer.

Question - the car ran great, do I need to dump the tank? Should I replace the fuel pump if it's working now (its only about a year old)? did the pump somehow rust shut internally (the tank is around 3/4 full with 93 octane fuel which probably has ethanol in it).

The fuel stabilizer will probably be good enough for now. I'd suggest taking it out on the road for at least an hour to work out all the issues that gasahol creates. Maybe even pump in a few gallons of fresh fuel into the tank, depending on how much fuel is still in there. FYI, when any car or internal combustion engine sits for 4 weeks the fuel and alcohol separate and the alcohol attracts moisture (water) which goes to the bottom and sits. This happens in the fuel tank, in the pump, in the fuel lines, in the carbs or injectors and so on. I don't think that I have to explain what happens with the water in the fuel system. For a fuel stabilizer in the future, there is only one product to use and it's not Sta-bil. That's an ok product and it keeps the fuel stabilized for up to 1 year but there is a product that is waaaaay better and most of you have probably heard of it. It's called Seafoam and they guarantee it to keep fuel stabilized up to 2 years. I'll take that a step further by letting everyone know that I"ve got first hand experience with the product and I've seen it keep fuel stabilized for over 4 years without any problems. I haven't checked my 79 620 fuel for over 2 years now but it was ok 2 years ago and I parked the truck in 2018 after I seafoamed the gas. My 75 z sat for 4.5 years and I put Seafoam in the gas the day I bought it in April 2018 and didn't start the engine until August 2022. I checked the fuel first and it smelled fine. Two days after I got it started I took off for the Olympic peninsula with it and drove it all over the place without a problem. Still driving the car today.

By the way, Z Specialties is alive and well, I never have closed for good, only the past locations were closed for good. I work out of my home now part time and I don't have any employees. Z man of Washington