Keep Rats Out of Your Car With Moth Balls.

Living in a rural area has it's charms such as seeing deer grazing on the lawn on frosty winter mornings or staring up at the milky way on cloudless nights without the light pollution of big cities. Rats, however are not among those charms.
Every winter the rats seek shelter in the walls and attic of my home and, for whatever reason, this year has been worse than it has been for a long time.
Normally they don't pose much of a problem but now there are so many of them that they need to take shelter anywhere they can, including inside the engine compartments of our cars.
First up was the BMW about two months ago with a blinker going out and the check engine light coming on so we took it to the shop and nearly $3000 later all the wires the rats had chewed up were repaired.
Since that car had been in the garage I assumed that was the reason the rats had gotten up into it for further protection from the cold.
Well you know what they say about people who ass.u.me things... So a couple weeks later the light comes on in the Explorer and a few days later it starts running really rough and gets a trip to the dealer. Thankfully, that one was only $700 in damage.
So before the Accord became the next victim I decided to try to do something about it.
 

Poison or traps didn't really seem like a viable option since two of the cars are outside, and I had heard from several sources that dryer sheets under the hood would help deter them, but that seemed kind of sketchy as well. How do you attach them under the hood so they dont fly away? How long do they last? How many do you need to use? I have no idea, so I turned to the trusty ol' internet in search of alternatives and it seems that aside from dryer sheets many people believe in the use of moth balls for the same purpose.
So I went out and got some, now how to stick 'em in the car so  that they stay...

I had some excess screen laying around from replacing a tattered window screen and that was basically the inspiration for this enclosure I am showing you how to make. If you don't have any, you can get a roll of it at the hardware store for a couple bucks, or just use your imagination and see what you can come up with as long as the material provides good air flow and is somewhat strong.
Besides the moth balls and screen, all you will really need is a pair of scissors, duct tape, hole making implements, some wire (I used picture hanging wire), and a pair of wire cutters/pliars.

I toyed with a few different ideas on how to accomplish this and finally fell back on the old faithful, duct tape!
Start by making a pile of both balls in the middle of a bit of screen, I cut mine to roughly a square foot but that's just because that was the width of the piece I had. Fold up the sides and corners until you have a little pouch that is flat on a side and tape it up. Just check out the pictures and you will understand.

Pick a nice juicy part and use your hole making implements to make a hole. I just used a hammer and a pointy thing that I think is meant for driving finishing nails into wood, but about any pointy thing would do.  After making a hole, flip it over and do the same from the other side and the duct tape will kind of cover ant frayed edges of the screen in the middle making a nice little tunnel.
Next, take your wire and run it through the hole, wrap it around and twist it off. Use the pliers to tighten the twists down until it's secure and then cut off something like an 8 inch lead or how ever much you think you will need for affixing the bundle.

Pop the hood on you car and look around for a spot where there is a bit of room, no moving parts for it to get fouled in, and where it is relatively cool.

The Pictures are of my Accord; the first two are candidates for placement, and the third is an example of where not to put it because of the radiator fan and the exhaust manifold.

I decided to attach it to the airbox where it's somewhat protected from direct heat by the battery.

It's been a couple weeks now since I put these in all the cars and it seems to have worked to a certain extent. The moth balls disintegrate more quickly in the cars that get used more often so this design would be better for a car that is mostly just sitting.
Also, I noticed that is says on the box not to breathe the fumes. I don't know how dangerous it could be but the smell is pretty strong and you probably don't want to be breathing it all the time. As long as the A/C or fan is not on while driving there should not be too much getting into the cabin.