Metallurgy Question

[gromitdj]

Ok, Maybe it's not exactly metallurgy (or is it?). But my question is, Do I stand any chance of remove this copper fitting from the Carboy washer that I made. The pump housing is cast aluminum and it's just a standard copper plumbing fitting that I used. Now, the wife wants me to use the pump to empty the inflatable pool that we have so I wanted to attach the plastic garden hose adapter to the pump. I've used a little heat and a pipe wrench, but that sucker feels like it's welded in there. Does anybody have any suggestions?

Thanks in advance!

 

[BreWirfel]

you can try using some good ol Coke (soda) coke is acidic, and will eat away some of the aluminum (not enough to damage anything) it works on bike frame/seat posts

other than that, i would say go to HD or Lowes and get some hose that fits over it and use that....will be cheaper than replacing the pump if you break something

 

[jds]

Metallurgist here, although this is as much a question for a good mechanic as anything else.

It looks to me like you have a couple of options:

(a) Liquid wrench, plus gentle heat on the pump housing + rap the end of the pipe a couple of times while cranking off the fitting. A cheater bar may help here. You stand a good chance of scorching / ruining the paint on the pump housing.
(b) Sweat a garden hose fitting on the end of the copper pipe, and thread the hose onto it. Quick, dirty, and shouldn't interfere with carboy washing duties.
(c) Use a snakebite (e.g. push-on) fitting to accomplish (b) instead of sweating the fitting on. It's more expensive, but you can always remove the snakebite fitting afterward and keep it handy for attaching other stuff to the pump.

If you've got the stuff to sweat the fitting, (b) is probably the way to go. Otherwise, (c) should get the job done for less than ten bucks.

Edited to add: If you go with (a), there's a good chance you'll gall the threads. You could chase them afterward with the appropriate sized tap, but my experience is that once you stick a dissimilar fitting together really well, it only comes apart without breaking something about half the time.

 

[EuBrew]

Modifying the copper pipe coming out gets my vote, heck of a lot safer and easier than risking messing up your pump!!

 

[lazybean]

It all depends on how much the threads corroded. Cast aluminum is notorious for welding threaded connections. I work on a Dock, and any time there is a threaded AL fitting more than a year old, we know it is going to be welded. you can try heating the cooper pipe, and placing a wet rag around the pump flange to keep it cool. that some times works, but usually not. You might be better off cutting the copper pipe, add a Union at the cut, so it can go right back after your done. You can then make a union to hose adapter to use for the pool any time you want.

If by chance you do get the fitting apart, i highly recommend you use Never-Seize on any AL fitting.

 

[EMPyre]

Nut splitter...?

 

[BrewBeemer]

I would saw the thread to slip fitting off just under the flats use a chisel to push in the threads towards the center of the fitting to collapse the threaded section to a smaller diameter. It will then about fall out. Clean the threads and use teflon tape next time and not torque it down tight.

 

[gromitdj]

Thanks everyone for your responses. I'll probably end up going with JDS' option B

Sweat a garden hose fitting on the end of the copper pipe, and thread the hose onto it. Quick, dirty, and shouldn't interfere with carboy washing duties.

Which, after all, it's a carboy washer first and a pool pump second.

Thanks Again.

 

[lazybean]

I would saw the thread to slip fitting off just under the flats use a chisel to push in the threads towards the center of the fitting to collapse the threaded section to a smaller diameter. It will then about fall out. Clean the threads and use teflon tape next time and not torque it down tight.

The way AL threads corrode, even if you just make it "snug" enough not to leak it will seize up tight. Teflon tape wont help with that ether, you need a corrosion inhibitor on the entire joint. I know from experience, enough so that now i try and avoid using anything cast Aluminum, its easier to deal with the weight of cast iron then AL.

 

[Yuri_Rage]

Nut splitter...?

Won't work very well on a male threaded fitting.

 

[BrewBeemer]

The way AL threads corrode, even if you just make it "snug" enough not to leak it will seize up tight. Teflon tape wont help with that ether, you need a corrosion inhibitor on the entire joint. I know from experience, enough so that now i try and avoid using anything cast Aluminum, its easier to deal with the weight of cast iron then AL.

Teflon on NPT torquing down hard will spit cast aluminum, even brass couplings will become bell shaped if over torqued.