I'm in the process of fixing my suspension and fuel delivery problems. I am going to drain the fuel tank and hopefully get it flushed at a shop sometime today. Any ideas on how long it will take and how much it'll cost? My more important question is what is the best way to clean out fuel lines, rather than buying new ones? Should I blow or send chemicals through the lines?
Thanks,
Scott

 

both

 

Many 7s have a drain plug on the fuel tank, empty it, then add fresh fuel and pump it through the lines, cleaning out any old fuel, and out the disconnected fuel line at the carb. Then change fuel filter and all should be good, i've done this for each of my cars when I get them and have no fuel delivery issues. You can also catch the fuel and establish you are getting enough fuel over a set time, ie; one minute into a measured container.

 

will the fuel pump get clogged with small varnish thats created in the fuel tank from sitting for a while?

 

The fuel filter goes before the fuel pump, buy a couple of new ones, they're cheap. If you have access to a compressor, you can blow the lines out, spray some brake clean in them and blow again. Do this in a safe envionment with plenty of ventilation and no ignition sources.

If you are dropping the tank, remove the fuel pickup unit and make sure those lines are clear. Often the filter sock at the bottom of the pickup line will split and the pickup tube will fill with rust and debris.. Removing the pickup also gives you another hole to help flush out the tank and inspect the internal condition. You will need to spray the screws securing the pickup with P B Blaster and let set, preferably overnite, then break them loose with an impact screw driver. I always replace the screws with allen head screws for the next time. If you are careful, you should be able to save the gasket.

If the tank is fairly clean and rust free, use dish soap and hot water to flush it, you shouldn't need to send it out. Flush and fill with soap a couple of times, then do the same with cold water only, 2 or 3 more. Add at least one bottle of Heet to the tank before adding fuel. If it is rusted badly, start looking for a replacement, refurbishing can get expensive if you outsource it.

Plan on spending a full day for this project, spray the screws, strap bolts and filler hose clamps the night before. You don't have to drop the tank to get to these, just be flexible.

Replace all soft lines while you have the tank out. If you have fuel injection, use only fuel injection rated hose, I use it anyway, even on carbs. Spend the extra money on the solid band clamps, a must for fi hose. You can find them in the Help section at the local parts store, if not they run 0.85 each here. If your pickup sock is shot, keep extra filters in your glove box. If you are running fi add a stock carb style filter, 3/8" barbed ends, pre-pump.

Always keep a spare fuel filter with you, once you disturb the tank, it can take a while for all of the crap to finally come out, even if you think you have it completely flushed clean.