Crystalline Deposits in Fuel Lines

[remoteQ]

Greetings!  First post, and glad to be here

 

As background, I'm working on an old(ish) Volvo which is coming out of long-term storage; and have a quick general question for the community today.  I think some folks might relate to this particular issue...

 

While attending to the car's fuel system prior to startup, I noticed a crystalline accumulation on the dry metallic in-tank componentry and the inner aspects of the car's fuel line runs.  As reference, the substance in question has the appearance of white-to-tan hard water deposits (it's crusty, not rusty -- and there's no sludge ).

 

So, since the crystalline deposits themselves seem to have come from evaporated fuel, is just refilling the lines with fresh fuel as a soak sufficient to bring this material into solution without further issue?

 

Or, is there a cleaner of some sort which the lines should be filled with as a dissolving soak prior to initial startup?

 

Any ideas/experiences to share?

 

Thank you for the input, and have a great day.

[ABear]

Hard to say for sure, I suspect it is a result of moisture that was in the fuel which attacked metal parts.

 

Folks think Ethanol in fuel is something new, it isn't has been fuels as far back as the 1960s although the concentration was lower back then. Combo of Ethanol, fuel and moisture can displace some of the protective galvanization layer on steel and when the fuel evaporates you can be left with a displaced layer from the galvanization and that may be the crystalization you see..

 

I would try a flush and clean out of all fuel system components, not sure what it will take to remove the build up but if you have crystals they may plug fuel filter or worse the carb or injection system.

[remoteQ]

Thanks, ABear, for stopping by

 

Not too sure about the corrosion theory, as scraping these deposits away from metal surfaces with a fingernail generally reveals clean plating underneath(!)  No appreciable rust on the bare steel bits, either.

 

Overall, it really does remind me of hard water deposits in old pipes...

 

I've attached the best pic I could get of an in-tank specimen (note the queer amber crystals on the ID).

 

[ABear]

Yeah, I have seen the white stuff like that build up typically on aluminum and pot metal carb surfaces after the fuel has evaporated. Typically takes mechanical scrubbing to remove as new fuel does not touch it. The yellow spots, don't remember seeing anything like that though.

 

Depending on age of the line in question, I would be more of the thought of just replacing said line as you don't really know the condition the entire length of the line.. Might develop pin holes once you start trying to clean out the build up.

 

Fuel tanks can often be steam cleaned or pressure washed without a lot of harm, although depending on age could develop pin holes when cleaning.. Although fuel tanks can be lined with specialized tank liner designed for use with gas if you have any doubts on condition of the tank.