How do Penetrating Oils Work??

[Jeff Higgins]

Kroil had a run as some sort of "magic" bore cleaner in the shooting sports, particularly bench rest and high power rifle match shooting. Its penetrating properties supposedly allowed it to work its way under powder and jacket fouling better than the bore cleaners specifically developed for that purpose. I never bought into it.

[Jims5543]

I saw this a while back, for loosening a rusted bolt, give this a try.

Edit - Safety nazi's are going to lose their minds with this video.

[javadog]

It’s pretty much the same type of candle I use, although I do use a heat gun.

[mepstein]

I just did some rusted parts today. Heat it up with MAP gas and as it cools, touch some paraffin to the threads. The paraffin acts as a lubricant but doesn't burn away like oil. But it's the heat that makes everything work.

[RWebb]

heat is great if the fastener is not near something that will be damaged (I ain't gonna buy an inductive heater for the one bolt a decade that is truculent...)

I ran out of Kroil (which is hard to get) and am using Wurth right now; pbBlaster stinks...

no idea if these are honest, but grist for the mill:

https://www.jenreviews.com/best-penetrating-oil/#Types_of_Penetrating_Oils

https://www.youtube.com/watch?v=st8dkGzJWtg

https://www.youtube.com/watch?v=xUEob2oAKVs

[Zeke]

Originally Posted by Jeff Higgins

To expand on ossiblue's explanation yes, the rust, galvanic corrosion, or whatever does in fact "grow" on the parent surface. When two mating surfaces have each "grown their own", they kind of interlock their respective corroded surfaces. Penetrating oil obviously cannot make two interlocking surfaces "glide" over one another - there is a hard mechanical lock between the two. What it can do, however, is make it much easier to break the bond formed between the corrosion and its parent surface. So, if you can break the nut's corrosion off of the nut, and the bolt's corrosion off of the bolt, you no longer have a hard mechanical lock. Now you have a rust and oil slurry between the nut and the bolt. That's the whole idea.

On a related note, the very best penetrating "oil" I have ever used is simply 50/50 ATF and acetone. The acetone acts as the carrier to get it in there and soon evaporates, leaving the ATF to loosen the corrosion. Only mix as much as you need - the acetone will evaporate from the mix, leaving you with ATF again. Doesn't hurt it - just add more acetone - but it does needlessly waste acetone if you're not using it right away.

Being on the forum for many years as well as the Garage Journal, I have read countless opinions about penetrating oils. Haven't tried the wax.

First of all Jeff and others are right about heat. Just about the only way you're gonna get air cooled exhaust nuts off — cherry red. Secondly, I mixed up and tried 50/50 acetone and trans fluid. For me anyway, it was worthless.

I have Kroil liquid and spray and it's a great product. If it doesn't get yer nuts off () it has many other uses and with the nano technology, it does penetrate. The new version of Liquid Wrench (if it is in fact new at all) seems to be the best for my using the penetrating oil practice and theory. A good method is to gently but quickly heat the bolt, stud, nut, whatever using a concentrated source and not turning the whole assembly into a massive heat sink.

At the right moment you can squirt your favorite product on the union. If it immediately turns to smoke — too soon. You should see it being sucked into the union much like the wax example shown above.

If you don't want to break the bolt or stud. you have to tap and wiggle ever so gently applying more heat and oil as needed. Once the union frees up, the battle ain't over. I like to try and expose a thread at the bottom on the union, apply more oil and run the nut or bolt back to secure. Rinse and repeat.

Of course I know I'm preaching to the choir here on Pelican.