3 year old Decalin no good?

[Vic]

Hey guys,

Im flying 100LL because I cant get ethanol free 93.  Closest they have is 91 at my local sunoco.

I have some old Decalin on the shelf, probably 3+ years old now.  
Is it junk and needs to be disposed of?

[Eddie Cesnalis]

gemini.google's reply= '

• Manufacturer's recommendations: While there might not be a specific expiry date, some manufacturers might suggest a timeframe for optimal performance. You can check the product label or contact the manufacturer for their recommendations.

Here are some resources that might be helpful:

• Aircraft Spruce, a supplier of Decalin RunUp, mentions a two-year shelf life but clarifies it's from the date of manufacture, not necessarily opening the container [Source about Decalin shelf life].
• User experiences on forums suggest it can remain usable for even longer periods, though some recommend using smaller containers to ensure fresher product [Source about Decalin shelf life on forums].

In conclusion: Your 3-year-old Decalin is likely still usable, especially if unopened and stored properly. However, if you're unsure or want the best performance, consider contacting the manufacturer or purchasing a fresher container. '

[Roger Lee]

Why not use the ethanol fuel? I've  used it for 2K+ hours at all altitudes with never an issue.

[FlyingMonkey]

3 hours ago, Vic said:

Hey guys,

Im flying 100LL because I cant get ethanol free 93.  Closest they have is 91 at my local sunoco.

What's wrong with 91?  That's the spec for the engine and there's certainly a margin of error built into that.

Ethanol is fine too in general.  Squirt in a gallon or two per side of 100LL if you're concerned, but you probably won't need it.