Penetrating Oil

I am intrigued by Dick L's comment in the post below concerning penetrating oil. Does this stuff really work or is it mainly psychological?

i think its more the pscholological, but i wouldnt know.....

Every body has their favorite brand but, in it's place, it works. It's place is in loosening chemical bonds.

For something that is stuck because it was quite simply wound down too tight, it's of limited if any use at all which I think (I'm never sure with Dick!) what he was referring to. In the case of the oil drain plug, those threads were sufficiently lubricated when the plug went back in. If the plug is stuck it's because some gorilla over-torqued it and penetrating oil ain't gonna help a bit.

If it's stuck because it hasn't been touched since the tractor was assembled 60 or more years ago, it can help. Rust is porous, and it's those pores that the stuff penetrates and wicks through to get some lubricant into the threads. I've been known to heat things up first and, after they've cooled down some but still considerably warm, to then apply whatever is at hand. You can watch a puddle of it draw in as the piece cools.

As far as spark plugs with crush gaskets(or without, too, I guess), it's a tossup in my mind as to how well it would work. Can't hurt, might help. Even if they were torqued to spec when installed, they stay in a lot longer these days than they used to and corrosion on the outside isn't that unusual anymore, especially if you live where they salt the roads, so a little jungle juice might help break up anything that might be binding the gaskets to the plug or to the head, as well as anything that might corrode where the plug meets the head.

It's more common and effective use is for things that are stuck from obvious or not so obvious corrosion.

I think most of them have their limits, though I've good results from using Free-All mfr'd by Gasoila, an industrial penetrant, I've tested it on some things I've found in old farmers dumps, totally immersed, works great under those conditions. I don't believe that any of them are miracle peformers, but within certain parameters this one is satisfactory.

Penetrating oil is a very useful tool but you would not use it to wash out your eye. I use it all the time Scotty. Thanks for the complement also Scotty. A bolt that screws into a taped hole or into a nut has clearance. If there is no gasket to stop the flow it (penetrating oil) will enter that clearance and lube the threads. Some brands have and acid that will help dissolve rust as it seeps into the clearance. Without clearance it would be a press fit and would remove the threads or twist off when trying to screw it in. A tapered pipe plug would be tight when it enters far enough to have no clearance. When the clearance is gone nothing will get past the threads.
I understand the not hurt part as long as it is not in your eye.

Recently had to disassemble a machine that had a sordid past, and spent quite a bunch of time in the fencerow. Had a bunch of larger threaded parts held with equally large rusted nuts. Treated all with several different penetrants we had around. Soaked them several times over several days. Fortunately, all came loose to an impact wrench. Looking at the threads as the fasteners came off, not one did the penetrant get into the threads. All were dry. Fortunately not badly rusted.

Sorry, about that, Dick! ;8^) The reference was to whether I wasn't sure how much you were tongue-in-cheek and whether or not you were talking about how the stuff isn't going to penetrate metal. And then my typing skills kicked in and I dropped the word "is" from a place it should have been and then . . . well, it woulda been a real big compliment over on Tales, but then . . .

I think the hole is deep enough now, so I'ma gonna quit diggin'!

How was supper?

I believe that penetrating oil has its place, but I've never seen it work the magic that some folks ascribe to it. Certainly, if you have an exposed, rusty thread (an exhaust manifold stud, for example), any lubrication helps. But for a fastener with no exposed threads, I have a hard time seeing how penetrating oil is supposed to soak into the threads.

I crack up when I read suggestions to use penetrating oil to loosen spark plugs, drain plugs, or my favorite, pipe plugs. How is oil supposed to get past a gasket or interference fit that is capable of holding oil or air under considerable pressure?

I know what works: Heat works. Get an acetylene torch and try it. You will be amazed. Use a brazing tip for small fasteners, and a cutting tip for the big stuff.

It was tongue in cheek to start with then I started thinking a gain, which was wrong for sure. Then when I see you had some wonder I got tickled. I like to listen to others think. Makes me smile inside and out.

Spark plugs...If the air doesn't come out under pressure,how is the oil going to get in.?

A friends tractor pumped oil so bad the oil ran out onto the block.Plugs were tight.

On plugs, I'm suggesting that it isn't so much a matter of corrosion on the threads, but corrosion around the outside of the seat or between any gaskets and the head or the body of the plug. Any or all of those will make a plug hard to start. And especially as plugs stay put for a lot longer these days, it's not unusual to see a little fine powder indicating corrosion on the top two or three turns of the thread when you do take them out. It's the crumbly stuff laying on the head just outside the plug hole that you try to wipe away without it falling back into the motor.