I did a search and came across an old post about putting ATX Fluid in the gas tank to clean dirty valves. Is this some kind of joke? Has anyone actually done this to clean their valves? If so were there any ill effects?
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IMHO the ATX fluid trick is for when you don't have anything else available. If you're not desparate, get some Redline Fuel System Cleaner. It'll do the same thing and do it a bit better than ATX fluid.
The Redline is great stuff but you need to make sure you are going to burn the full tank within a few days.
It will eat fuel lines if left in the system too long.

I have used it on newer engines by letting the engine suck it through a smaller vacuum line on a warmed up engine only using about a quater of a quart. Then I shut the engine off for about an hour to let it soak everything. Then when you crank it up it is smoke time For 15 minutes.
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