With the compressor running?? That's very odd. I would look to the compressor as problem. If the compressor was not running, then I would look for the reason why. As far as the dryer goes, it should always be changed anytime you tear into any refrigeration system. If you indeed have a restriction otherwise, you need to find it.... but it sounds like you are saying the problem is dynamic?? If so, then yes the expansion device (or TXV) is failing and should be changed. Just make darn sure you have taken the heater out of the equation somehow. Make sure to evacuate and recharge with the proper amount for the new or bastardized system. Also, putting 2.5 pounds in and removing 2 pounds is what we call leaking lol
