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Old gas in new gas tank

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AUSMHLY

AUSMHLY

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Gas has been sitting in my new gas tank for a year and a half. I will empty it. Question is, do I need to do anything to the inside of the tank? Any product I should pour in to clean it, then emply? Bring it to a radiator place and have them do it? Or simply empty the gas and fill it with new gas. Thank you, Roger
 
I'd shine a flashlight in there to see if you need to do anything at all. Many cars have sat for much longer with much older gas and not required any special treatment.

If the inside passes a visual inspection, I'd suggest starting with nothing more than clean fuel filters. After a few weeks you may want to replace any fuel filters again just to be cautious... but I doubt it will be necessary.
 
Thank you Doug. Someone told me that old gas will leave deposits in the bottom of the tank. A sort of sludge. Is this true? Does it matter? Anyone?
 
Por 15 (and Moss too) carries a product called Marine Clean which can be used to clean out gum, sludge and varnish from a gas tank. Here's a link with instructions:

https://www.por15store.com/POR-15-Tank-Sealer-Instructions.html

I should be doing mine shortly .. maybe this weekend so I'll let you know how it goes.

Cheers,
John
 
My experience with things that have not been run for a long time is not so much with the old gas in the tank, but if the tank sits empty or partially full, rust can form in the tank and clog things up. Also, when gas evaporites in the float bowls etc., it can form a kind of varnish which can cause things to stick. If you can add a good quantity of fresh gas, and if it will start it probably will be OK, but definitely use a filter and change it often as suggested above.
 
Should you want to clean the tank, Marine Clean mentioned above is wicked strong stuff. It will definitely get the deposits out. Be sure to wear heavy rubber/vinyl gloves when working with it our you'll end up with hurting hands and discolored nails.

A year and a half may sound like a long time but with modern fuels it's not a terribly long period for fuel to sit. I'd definitely replace the fuel and while the tank's empty examine it. I doubt it's been sitting long enough to develop significant rust or sludge at the bottom.
 
Are you getting that close to getting your baby back and on the road? I vote for new filters and fresh gas. I'd be more concerned with the carbs if gas was left in there due to the smaller quantity and the tendency for gas to evaporate and turn to varnish.
 
Thanks guys. Yes John Loftus, please let me know how it works out.

Tahoe healey, not getting my hopes up just yet. This month makes one and a half years away from me. Current shop has had it one year. He told me last month, he'd have it painted middle of this month. But his track record for telling the truth is like the old saying, how do you know when a car salesmen is lieing? His lips move.
 
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