What type of penetrating oil works best?

HMF

HMF

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Hey Guys,

I have read that most penetrating oils are oil with some sort of solvent mixed together as a carrier.

Kroil, for example, lists three active ingredients on the MSDS:

1. Petroleum Base Oil
2. Naptha
3. Mineral Spirits (Aliphatic Petroleum Distillate)

I've heard of people using acetone & ATF, spindle oil + mineral spirits or acetone, brake fluid, kerosene, varsol, and ATF ("Ed's Red Mixture"), Mopar Rust Penetrant, 50/50 ATF and mineral Turpsentine.

What type of penetrating oil do YOU find works best for freeing up rusted nuts and bolts?

Thanks,

Nelson
 
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You can try all the oils you want, but when that fails use heat, works every time. It worked on my 9a gear box when all else failed. I just put the little electric ceramic heater next to the open end of the box, which heated the gears and expanded them so I could move them, I wasted days on oils. A torch will work on things that does not have anything that will be melted or ruined. Ask any DIY car guys on how they get rusted bolts off of exaust. You can buy those little torches at the hardware stores or go for the big sets at welding supply places.
Paul
 
Hi,

I too vote for Kroil as working the best on rusted nuts.

Let it soak awhile and also tap the part lightly with a hammer to vibrate it.

Another useful fluid around the shop is Marvel Mystery Oil...if for nothing else but the smell ;-)

PaulS
 
LPS KB 88 I used to use Kroil til I found KB 88. FYI don't use KB 88 on rusted nuts in the verticle position with the nuts pointed down. Any vibration at all and the nuts will back off and fall to the floor making them difficult to find. ;D

Pat
 
I have have good results with a home brew of 50% Marvel Mystery Oil and 50% Acetone. I also like PB Blaster but as was mentioned earlier heat applied properly will work wonders. A bit off the subject but items placed in an electrolysis vat will loosen up better than using penetrating oil or heat in many cases. Of course there are many things a person would not want to submerge in water.

Bill
 
A tip from an old school millwright that is now resting in peace:

On the most stubborn fasteners...after adding heat with a torch, put some bee's wax on the stubborn threads. Bee's wax will soak into the pores of the metal due to the smallest molecules of any liquid.
He swore by it.
 
+1 for Kroil by the gallon 8^)

It may not be perfect, but I haven't found anything better. Sometimes you just have to add a little "Time" to the mix.

Randy
 
Kroil is SO good, it works without even being used!

Well, it seems that way for me. About 4 years ago I bought a gallon of Kroil, and since then I've not encountered a single rusted nut that I couldn't unscrew without it. Kinda like carrying an umbrella, I guess - if I carry one, it doesn't rain. . .
 
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