How can I prevent bees (or yellow jackets) from building another nest under my gas cap cover?

Wow. You must not fill up often!

Wipe the area with rubbing alcohol (won’t damage the paint) and then with citronella or lemon oil.

That will deter the beasties.

edit to add:
Not all bees leave a stinger behind. The only thing that matters is if you had a bad reaction to the sting. (bad reaction meaning difficulty breathing or extreme swelling)

the bigger question is, how did the bees get into a sealed container?

I would spray the area with a light coating of white Lithium grease or WD-40. It will discourage them from attaching to the metal and lubricate your filler door and gas cap as well. Win-Win

It sounds to me more like paper wasps of some kind. I think if you coated the inside of the gas cap with vaseline, they would leave it alone. I also think you need to figure out how the heck they got in there; isn’t the gas cap supposed to have a seal?

Thanks everybody.

@ragingloli
I guess I didn’t describe it as clearly as I thought I did.

There is a screw-on cap (gas cap) covering the hole in which the gas hose nozzle is placed. If screwed on properly, this is a tight seal.

But there is also a hinged door over this gas cap which I termed the “gas cap cover.”

The gas cap is obviously very secure. The cover (the hinged door) isn’t that tight. It also has a raised area in which you place your finger in order to swing it out to access the screw on cap.

So that allowed them enough room to get in and out and also to build a rather skinny nest around the size of a fat quarter.

@LuckyGuy
I’ve never heard of Lithium grease. The only Lithium I’ve ever heard about is that which is used as a medication for bi- polar.

Where exactly does one find Lithium grease and is it as oily (and smelly) as WD 40?

Would lemon oil do the job just as well since its also slippery. It smells a whole lot better than anything else. But if it would not be effective, then I guess I’d have to use one of the other suggestions.

The main advantage of WD 40 is that it comes in a spray can and might be a lot easier to apply than something like Vaseline.

@ccrow

Aren’t wasps solid color black or dark brown and rather larger than either bees or YJ?

These definitely had yellow (not sure if they were yellow and black striped or just yellow like bees) I was a bit distracted by both the pain and the necessity of getting them out of there so I could get gas :)

This has definitely been one of the stranger interludes of my life, to put it mildly. Fortunately I’m not allergic to bee stings and surprisingly, the pain had pretty much dissipated by the time I finished my shopping.

Nonetheless, its not an experience I’d ever want to repeat.

@butt_onstc in that case, you could go to your local hardware store and buy some rubber seals and glue them on the lid where needed.

There are paper wasps that are black and yellow. And they’re not much different in size from yellowjackets(which are much nosier, and much, much nastier IMO!).Paper wasps like nice, protected spots for their nests, and I’m sure your gas fill cover had a big ‘vacancy’ sign on it as far as they were concerned:-) And they can build those nests pretty fast. WD40 vs vaseline – I think either would work, but the WD40 is a lot thinner and might drip off; it also probably wouldn’t last as long. You could, I suppose, try using some kind if insecticide spray that has a residual action on there… like ant & roach killer. The wasp killers are generally long-range, foaming sprays designed to immobilize a bunch of pissed-off wasps before they can get to you. Or, like @ragingloli said, glue something in there to fill up the space they were using.

I use White Lithium Grease by CRC . It is in a 10 ounce spray can. It’s odorless but it does leave a white coating. I get it at the auto parts store. It is more permanent than WD-40. Perfect for your garden tools.