In our last article I covered the basic things you can check and do to make sure your farm, barn, or garage fresh find is suitable to run. Once you’ve brought the vehicle back to life and confirmed the engine isn’t trashed, you can work on making it run on its own consistently. The biggest piece of the puzzle is to get the fuel system cleaned out and suitable for use again.
This process isn’t going to be fun and normally requires complete disassembly of the fuel system from front to back of the car. The first step is to drain the fuel tank of any old fuel and see what comes out. Luckily for me my ’52 had a drain plug in the bottom of the tank I was able to drain out. Other vehicles may require you to remove the fuel feed line. Take notice what the fuel coming out looks like. Does it have flakes of rust in it? Is it chunky or getting clogged coming out? You can almost guarantee that if your vehicle has a steel fuel tank in it you’ll have a good amount of rust in your fuel. The other thing about leaving a car sit for years with fuel in the tank is that the fuel will slowly start solidifying. I’ve seen it so bad that it turns completely solid and looks almost like a piece of coal! In my case I had half fuel and half solidified fuel that was coating the inside of the tank. I had to remove the tank to get it cleaned out, but you may be able to save the tank by pouring kerosene, diesel fuel, or a chemical like acetone in the tank to flush the junk out.
Once you remove the tank you need to figure out how bad the tank really is and if it can be saved. In my particular case the previous owner had tried to be pro-active in the late 80’s-early 90’s and have the fuel tank resealed and “restored”. The shop stripped the tank, poured in a tank sealer and undercoated over the rust holes on the outside of the tank. Surprisingly it held up for years, but after sitting with old fuel in the tank for so long, the sealer failed and was melting off of the inside of the tank and clogging things up. That plus the rust holes the shop had undercoated over meant I needed a new reproduction tank and sender. If your tank isn’t rotten and just has surface rust you can follow the fuel tank restoration how-to I posted a few years back to restore your tank for many more years of use!
After you have restored or replaced your fuel tank, you need to work your way forward inspection the fuel lines on the car. As a rule of thumb I replace ANY old rubber fuel lines that show cracking in them. The hard fuel lines can be salvaged if they don’t look rusty or seem to be seeping any fuel. Start by cleaning out the ends of the hard line with a pick. Usually you’ll find varnished fuel clogging the ends of the lines. I then kept flushing the fuel line with Eastwood Aerosol Injected Cleaner. My line was pretty clogged and took a few sessions with the pick, flushing it then digging the ends open again and reflushing, but Aerosol Injection really made life easier as it helped force the junk out and partially dissolve it in one go. Once I got the line free and fluid was being forced out the far end, I continued to flush the line with the cleaner until I had clear fluid coming out of the end. On my vehicle I chose to remove the entire hard line to inspect and clean it, but you can do this process on the vehicle.
Once the main fuel lines on the vehicle are cleaned and clear (or replaced) you can move forward to the engine side of the fuel delivery. If you have an older carbureted vehicle you will find the oil pump mounted to the block. You have a 50/50 chance of the pump still being good, but in order to check if the pump is any good you need to clean the lines coming in and out of the pump. I followed the same procedure as under the car and cleaned the lines and then the glass fuel bowl filter with Chassis Kleen. If you’re replacing a disposable fuel filter in the engine bay I’d suggest getting a clear fuel filter that you can watch as you start the engine again. If you have a mechanical fuel pump you want to check and see if the pump is still any good. Once you get the fuel pump going and pulling or pushing fuel to your fuel filter, watch to see what rushes into the filter. You will probably see more of that muddy/rusty fuel come through and it may require you to replace or clean the fuel filter a few times before sediment-free fuel is flowing through.
Once I had clean fuel flowing through the fuel lines from tank to the front of the car I decided to disassemble the carburetor and clean any varnished fuel out of the carburetor and reseal it. Once the fuel system was fully assembled the car I fired her up and made sure everything was jiving. From here you may need to readjust your carb or fuel system and ignition timing to work with the modern unleaded fuel available today.
I can honestly say this was one of the least fun parts of getting my ’52 Chevy running again, but it was one of the most gratifying after seeing how bad everything was when I started! Once I had the car running on its own I decided to take it for a drive down my driveway and the brake pedal promptly sunk to the floor… so you can guess what my next installment will be!