I hate to be a contrarian but WD40 absolutely positively does not “attract” water. Alcohol is hygroscopic and alcohol is one component of our nitro fuel. The whole purpose of the after run process is to flush out the alcohol. I’m sure everyone can come up with some anecdotal evidence or second hand story of someone who religiously did there ARP and there engine was so pitted you could see daylight through the crankcase. Of course your friend “claimed” he was religious about it most likely it was seldom done and since you were not there every time you really don’t know.

Several engine manufactures suggest to use WD40 and I really don’t believe it would be in there best interest to so without a foundation of knowledge of that product. They don’t manufacture WD40 and don’t sell it so there would be absolutely no monetary incentive for them to do so.

If you live in a dry climate you can certainly get by without doing your ARP much easier than someone in a coastal region. When I lived on the Texas coast I had to drain my air compressor every day and would get several cups of water out. Here in Colorado I very seldom see more than a few drops of water running the compressor under the same conditions.

Does anyone know what WD40 stands for? “Water displacement perfected on the 40th try.” Would you like to learn more? http://www.wd40.com/AboutUs/our_history.html

All this being said, I use WD40 for my ARP and if the car is going to sit for a while I follow the WD40 with a few drops of after run oil. It may be over kill but it takes only seconds to do and I can see no downside to it.

I’m also suspicious of any fuel that claims you don’t need to do ARP. Their fuel still has alcohol in it and that’s what the ARP does is flush the alcohol out. It wouldn’t matter if it has after run oil in it, you need to flush out the alcohol. If you are comfortable with not doing your ARP or you live in a dry enough climate to “get by” without doing it great but it wouldn’t be something I would be comfortable recommending.

Sorry for the long rant but I found some of the misinformation so egregious I couldn’t keep my mouth shut. I’m sure I will ruffle someone’s feathers with this. That’s not my intent.

BTW: I am not a representative, salesman nor do I own any WD40 stock. I just hate to see any product slammed by someone who has no actual knowledge of the product.