Kroil calls itself 'The Oil that Creeps'. Or is it the oil FOR creeps?
I am a fan of Kroil, but what often makes the job work for me is the good ol' Hot Wrench. Soak the offending item with penetrating oil, then give a number of heating/cooling cycles with extra oil added in between.
In my mind (a risky place to venture) I picture the parts expanding and contracting, crushing those rough chunks of rust and allowing the penetrant deeper into the joint.
This does not always require blazing red-hot torch-work. In sensitive areas a soldering gun can be carefully used to heat a nut or a screw head while minimizing heat to the surrounding structures.
Regardless of what is really happening in those microscopic spaces, this process has saved many jobs where I truly expected to twist off nuts or screw heads trying to back them out.
This is one of those areas where patience is certainly a virtue. If you can bring yourself to oil and heat a few times, then walk away from it for an hour or a day before trying again, you just might have the satisfaction of getting that little beast apart without breaking anything.
What have you found to help in getting those ancient rusty items apart? I'm always looking for new ideas to try out.
Take a look at this
Or look for 'How to make Penetrating OIL', which is just down a few days.
The other ingredient is time. You have to wait for these things to work.
Well I think alot of folks miss a simple step in getting rusty things apart.
The FIRST thing I do to a rusty fastener or part that should move is remove as much rust as possible by media blasting or wire brush or pocket knife. whatever it takes to remove as much of the barriers as possible so the penetrant can get into the problem area.
Take a rusty cylinder and piston for example.
If you look in there and it is 1/2 thick in rust and mud, there is no need to spray anything yet. Get it out.Keep cleaning till you see the separation between piston and cylinder at the very top. it takes a while . But once you see that, then apply the oil.
Vibration is also your friend in breaking stuff loose with penetrant. You can read the can and confirm. A light peck with a small hammer or a wrench lightly worked back and forth on a bolt head helps.
Heat is also good. But I usually try heat if it looks like a bolt head could round off or other methods don't work.
Then I use it as little as possible.
I have tried the old battery charger trick that you apply 1 cable to each item, like a bolt head and a block but never had any results from it.Supposedly the current arcing in the bolt threads is supposed to make heat and help break the bolt free.
But as said above, takeing your time is most important. Don't get in a hurry.You can break irreplaceable parts or expensive parts.
And another issue.
When something finally does break free, it does not mean the last chemical you sprayed on it did the trick if you use more than 1 thing.
I have over heard folks say something like," Oh I have sprayed 4 different things on it and PB blaster broke it loose.".
Well maby not, the other stuff you sprayed in there may have just got into the problem spot after some time. And other chemicals like wd-40 may not let Kroil into a problem area at all..Some folks still think wd-40 is a penetrant.
An electric paint stripping gun works well for delicate jobs like removing a brass needle seat from a cast Model T carby (vaporiser). Chris.
I'm with Mack. Back in the early '60's I was told that WD 40 was a good penetrant. Very many folks still believe that. It was many, many years later that I learned that it isn't. That being said, it is VERY useful for MANY things other than a water dispersent, which is what it was designed for, and is very good at. It is one of the best things that I ever found that would keep the front mounted distributer from drowning out on an FE block Ford engine. I had a list sent to me a few years ago for the other things that it is good for, but I can't find it now. Maybe a Google search? It's actually kind of amazing what it can do. JMHO. Dave
"2000 Uses" To channel Homer Simpson, "Is There Anything It Can't Do????"
There are some fasteners and connected parts that no amount of time or snake oil will separate. Nothing works better than heat on these kinds of problems. If that doesn't work, destruction of one part or the other is in the cards. Many times I have had to use the Victor hot wrench to slice a junk crank and rods out of a valuable block and break up the iron pistons and remove them in pieces. I have a lot more cranks and rods, sometimes you have to sacrifice one part to save another. I just save the part that harder to replace. Not every T part can or should be saved.