Lakota said:
Before using and penetrating fluid you should add vibration by hammering, etc to break the rust bond and giving the fluid a path to move into. Soaking over time helps.
Tim37 said:
The secret is time. If I know ahead of time that I'm gonna be working on rusted bolts I start spraying them with pb a day or two in advance if possible. It really helps.
(emphasis added)
These gentlemen raise salient points above, although I would advise against the use of the proverbial "BFH" on a frozen nut or bolt. I use a little ball peen and a drift punch with a
light tappity-tap-tappity-tap while applying the penetrating oil.
We sold "Liquid Wrench". Made by Radiator Specialty in Charlotte, NC. (Looks like they've moved and changed their name to "RSC".)
Also sold K&W "Knock'er Loose" retail and as a manufacturer's agent.
I can state confidently that the K&W product beats "Liquid Wrench" hands down.
As an aside, I generally ordered
any brand of "penetrating oil" on any order from a chemical company because it made it easier to make freight prepaid terms (as in the case of Radiator Specialty), but I never saw one that worked as well as the K&W.
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Best I can offer is my favorite "Knock'er Loose" testimonial:
On the counter one weekend afternoon at our Yelm store, an old boy came in and picked up a can of "K&W Knock'er Loose". We carried it in both an aerosol can and a pint liquid can then. I can't recall which one he bought.
He came in the next afternoon and bought two more cans. I had to ask him why.
Apparently he'd been fighting with a frozen track bolt on one of his pieces of equipment all morning and early afternoon the day before. He'd tried "Liquid Wrench", "WD-40", and a torch.
He told me he went home with the "Knock'er Loose", hosed that bolt good, went back into the house and had lunch, and then went back out and took the bolt out
with his fingers.
It may well have been that his previous attempts with other products and heat may have had a significant effect.
That said, he was one of our regular customers, and wasn't known for telling tall tales or hyperbole; one of those guys who played his cards pretty close to his vest.
==
A personal friend of mine, who I've known for over 30 years, started working on mini-bikes when he was a kid in the early 1960s. He won't use anything else.
Some of the old timers on the mytractorforum dot com site insist the best thing is straight kerosene, but I've never tried that method.
I've never tried "Kroil" or "PB" myself, but I see "PB" in all the parts stores. I'll pick up a can and try it on the next frozen blade bolt or blade adapter I run into and return with a report.
In the meantime:
K&W Knock'er Loose #1716 16 oz. can by
four.cycle, on Flickr