Fuel line Options

[GaK10]

What options are there to remove the trash from the lines without hard line replacement?
Now for the back story.
I had bad fuel in my tanks after sitting for years. The tanks/sending units have been replaced and the carb was cleaned. When I went to start it, it would fire and shut down. Happened wire a few times.
I diagnosed the issue and so far I have contaminants in the fuel lines. I discovered this by the color of the new gas being rusted and by evidence in the fuel pump after disassembly.
Years ago I replaced the block and installed a Holley Red pump instead of the old mechanical pump due to the block not prepped for the old pump. Good thing about the Holley is it can be disassembled and cleaned. The pump is not located in the right spot but is located in the proximity of the mechanical fuel pump. It’s actually bolted to the fender below the coolant reservoir. I’ll get to relocating it later but for now I’m trying to get her back running.
I have a standard in line filter between the regulator and the barn but nothing between the pump and tanks. I was thinking about putting a large fuel filter between the pump and tanks, running it until the trash is gone. The lines seem usable, at least from the outside. What are ways/processes to clean the lines with minimal work?

Looking forward to see everyone’s ideas.

 

[Ricko1966]

Disconnect them front and rear and blow them out with compressed air blow through them for awhile so all the scale and crap comes loose them put a filter before the pump and check it often.

 

[SirRobyn0]

I think my answer would be it depends on if your think the metal hard lines are rusty inside. If they are rusty inside the only long term solution is replacement. If you think it's mostly just funk from the tank, then I'd remove and replace all the rubber lines. After 40 years they are past their prime. Then I'd blow air though the hardlines before installing the new rubber lines. Like Rick said put a filter before the pump and expect it to need to be changed a few times while stuff breaks loose and collects in it.

 

[Scott91370]

Brake cleaner may help loosen it up some then as other said, compressed air. Do it front to back and back to front.

 

[GaK10]

Thank y’all. This is what I ended up doing. Went to NAPA and got a 2 micron fuel filter, one that will match up with my duramax (because I have extra filters) which has a CAT 1R-0750 filter, and a base to accept. I put it between the hard line and the pump (with a clear inline filter between). I disconnected the line that goes to the carb and ran it to an external reservoir (5 gallon gas tank). I ran multiple gallons through each tank, repeatedly….. hours, switching each task back and forth. I put marvel mystery oil in there too. The filter did great and made the fuel look clean on the first run.
Since the fuel still looked clean after hours, I just kept putting it back in each tank and ran it back through… $$$ saver. I did have a clear inline filter from a prior replacement I used to see the color of the gas coming to the pump inlet after the 2 micron filter. It worked although the regulator wouldn’t read, which I didn’t care.
After multiple gallons, I took the clear inline filter off and ran the large filter straight to the pump. The regulator then gave a consistent reading of 6 psig. Fired her up and she ran, would say no issue but have some carb problems. Gotta rebuild it.
Thanks to each one of you for guidance. Positive results.
Hope this post helps someone. $65 total on the filter and base.