How Do You Clean Out Metal Fuel Lines

[Chipps]

After removing the fuel tank from a 1973 Spider I see whay the fuel pressure light was on. It is full of junk. I have installed a new fuel tank. I will be replacing all of the rubber fuel lines. But do I need to cleanout the metal fuel lines? If I need to do this , how do you do such a thing? Is it safe to do this sort of thing?

[Gordon Raymond]

Here is what I have done in the past. Disconnect both ends of the line. Wrap the tank end with a particle mask, the kind you wear when sanding, grinding or working in dust. Blow from the engine end with compressed air, gently first to get fuel out then stronger to dislodge crud. Examine the mask. Goop, OK, rust, not so good. Next, with a helper, allowing air out the tank end with ones thumb over the end, fill from the engine end with spray carb cleaner. ( It takes about 1/2 can!). The engine end is high enough so it's ok, but now to rescue the guy with his thumb on the tank end, find something (like a golf tee) to jam into that end. Go away for a while. Then drain the line through a coffee filter or particle mask again, and blow with compressed air. Light brownish goop, still OK, rust (particularly hunks) BAD! Check hunks or possible rust dust with a small magnet. If there is rust, it is best to replace the line. There is no telling how bad (read about to leak) the internal corrosion is, and fuel line leaks can be disasterous. The light brownish goop is fuel varnish and not as big a worry. So far I have found most with no rust, but some with rust for sure that required replacement.
I hope this helps. Gordon Raymond

[pathung]

Good tip there, Gordon! I might have to do this to check the line's integrity.