My experience is whether it is a cheap tool or an expensive tool, getting the damn things to come loose is actually more a matter of technique. I’ve had the plastic rings with a slot in them, pot metal rings with a slot in them, and even had one that looked like a pair of scissors where half the ring was on one side and half the ring was on the other side. If you can get that one into the location, I liked it because not only could you hold it steady, you could gently tap on the arms of the scissor part to push it in a little deeper, and pop it in better, which pops it loose better. Of course the scissor tools I had, we’re also made out of pot metal, so you couldn’t tap them very hard or they break..
Understand what it is you’re trying to do. In the old days, there was an O-ring and a hard plastic/rubber connector piece that was about the same size as the O-ring, but it had a couple of edges to hold it in place. The O-ring made the seal between the inner tube and outer tube, and that slightly bigger different shaped piece locked the tubes slinky into the kind of double crimped end (think brake line), which kept the two pipes from sliding in and out of each other.
Most of what I’ve seen for the last 30 years, you still have the little green O-ring, but then the other connector part looks like a metal O-ring, but it’s actually a spring that looks like a teeny tiny slinky, connected in a loop.
This was the best picture I could find, but if you look in the lower left of the loop, you can see the coils of the spring.
When you’re sliding the little tool down in the fitting, you are trying to expand that spring ring a whopping 32nd or 64th of an inch to let the O-ring part slide out underneath it. On both the fuel systems and on the AC systems, and in industry we had them on some other things, the whole thing seizes up after a few years. So when you put the tool on there, regardless of the style, you almost have to tap it down gently to get that rubber ring or that spring ring to expand enough, so the O-ring can slide out underneath it.
In my experience, once you get your technique down, 2/3 of them kind of pop off pretty easily. The problem is the other third are kind of frozen in there and you have to get pretty aggressive with them to get that spring or that rubber locker to release. Avoid pliers or vice grips or using enough force that you might actually bend one of the tubes. It’s more a matter of forcefully, wiggling it out, then just pure tension bowling. I’ve to use a pretty good amount of force, (1) pulling on the one pipe and (2) pulling on the other pipe while I’m (3) holding the tool in place and (4) pushing the tool down to release the spring. Each item using a hand.
Hey wait a minute, that would take three or four hands….
Therein lies the problem.
And of course half of them are located in place where you’ve only got an inch or two around the outside of the thing to work.
One last thought, very seriously, no joking, make sure there is no pressure in the system. First, if there’s pressure in the system, that is actually holding that joint together harder than if there’s no pressure, and second, when you do pop it loose, you don’t want a face full of fuel or Freon or whatever
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