use two pipe wrenches. one to hold the pipe and another to loosen the cap. if you can't move it with the wrench alone, use a cheater bar. the line is probably no larger than 3/4'' and unless it is completely rusted i don't see why 2 pipe wrenches wouldn't work. buy the caps and pipe dope for the other two lines.
Grip the fitting you are trying to separate with one pipe wrench; grip the pipe to which it is attached with another. Hold the pipe steady while you turn the fitting counterclockwise with respect to the pipe. Spray more lubricant and wait an additional five to 10 minutes if the fitting won't turn, then try again.
Have one person twist one pipe one direction, and another person twist the other pipe in the opposite direction. While they are twisting and pulling, try tapping the area they are joined with a hammer. The strikes and vibration may help loosen things up.
Try a real penetrant like Kroil or Creep. Get the pipe hot and then quench with water to rapidly cool it. The contraction may loosen the threads enough to move. If it does, spray with the lube and keep turning. Last resort is to cut the threads flush with a plumbers tool and use a SharkBite connector and PEX.
Usually heating the pipe will loosen it enough to turn. Try turning it clockwise (actually tightening it) to get it to budge then once it budges you should be able to loosen it. Also vice grips isn't going to do it. You need a 14" or larger pipewrench.
Use a couple of purpose built pipe wrench s. One on the fitting and one on the pipe you are trying to remove it from. Be sure the wrenches are orientated so that as you turn them their jaws are locking on the fitting/pipe. If this doesn't work, heat up only the fitting with a propane torch while wrenching on it.
To avoid scratching your plumbing fixtures: Use a strap wrench instead of pliers or a pipe wrench.
However, this versatile and widely-used lubricant and penetrating oil can be surprisingly effective in tackling various common plumbing problems. There are many times that customers call a plumber in Glasgow when in actual fact, a simple spray of WD40 is all they needed to fix the issue.
Un-sticking two stuck pipes.
If you you use two pipe wrenches and a small floor jack the pipe comes right out. You'll need to put the jack on the inside of the hoop, on the outside you'll bind the pipe.
Apply the lubricant spray
Then, take your WD-40 Specialist Penetrant Spray. This product specifically targets corroded and rusted components, and helps to loosen them easily.
Pipe Wrenches
One type of adjustable wrench is a pipe wrench, the workhorse of a plumber's toolkit. Available in various sizes, they are designed to grip and turn pipes and fittings. Their adjustable jaws provide a strong grip and make loosening or tightening threaded pipes a breeze.
Use Heat to Loosen the Fitting
Heat Source: Use a propane torch to apply heat to the fitting. This helps expand the metal slightly, breaking the bond formed by the corrosion. Application: Hold the torch about 6-8 inches away from the fitting and move it evenly around the area.
If you can't see any damage or build up on the tap, it may simply require a little bit of additional force. Grab a wrench and gently but firmly turn the tap anti-clockwise until it begins to move. Be careful to not apply too much pressure, as you don't want to damage the tap accidentally.
You can also try a lubricating product like WD-40. Apply it to the area around the threaded fitting or joint and wait a few minutes for the product to make its way into the connection. Then use the pipe wrench or your hands to twist the pipe counterclockwise until it is loose enough to remove.
Grip the fitting you are trying to separate with one pipe wrench; grip the pipe to which it is attached with another. Hold the pipe steady while you turn the fitting counterclockwise concerning the pipe. Spray more lubricant and wait an additional five to 10 minutes if the fitting won't turn, then try again.
When the plug is red hot, quench it with water. It will cool off rapidly and be steaming. Wait about five seconds and then use your wrench. You will find that you can remove the plug easily.
Apply heat to the stuck fixture or plumbing nut with a hair dryer or heat gun. You may not want to drain all the water out of the fixture before applying the heat since the water will be a heat sink for the inner part and the fastener will have a bigger variation in temperature quicker.
The rubber gloves allow you to get a tighter grip when attempting to loosen the P-trap nuts by hand. If the rubber gloves don't work, go ahead and use the plumbers wrench. Hold the P-trap with one hand while you twist the P-trap nut with the wrench. Once you have loosened it, finish unscrewing by hand.
For PVC glue that has started to set, you'll need to use acetone on a clean cloth to wipe it away. When the glue has been allowed to fully dry on the PVC pipe, you'll need to use a special solvent to break down and loosen up that bond. Using acetone won't be enough in this case.
Using the right sized spanner or an adjustable wrench, tighten the nut a little, then give it a wriggle before trying to loosen it again (remember righty tighty, lefty loosey!). Turn on the heat. Heat makes metal expand, so applying a little heat to the nut could make it expand enough to loosen.
Salt, Vinegar, and Flour – You can mix equal parts of salt, vinegar, and flour into a paste. Wear gloves and use a microfiber cloth to rub the paste all over the affected areas of the pipe. Let the paste sit for 30 minutes, and wipe it clean with a damp or soapy towel.
Get a heat gun (electric, not a flame type) and heat the piece of pipe inside the fitting, very carefully, without overheating the fitting itself, at the same time use a small, flat-bladed screwdriver to start to separate the pipe inside the fitting and the fitting itself.