I've always taken them apart when that's possible. When it's not, I've sometimes wrapped a wet rag around the center of the fitting before soldering. I have no way of determining whether it helps, but if the rag is still steaming (not completely dried out) when I get a good soldered joint I figure it's probably provided some cooling at that location.
The problem with damaged valves is that they usually work fine in the open position. A valve that is permanently open during normal use---the shut off for the supply side on a water heater, for instance---may not let you know that it's not going to work just when you really need it.
Same-Day Shipping! Most of our stocked parts ship the same day you order (M-F). Expedited shipping available, just call! Most prices for parts and manuals are below our competitors. Compare our super low shipping rates! We have the parts you need to repair your tractor. We are a Company you can trust and have generous return policies! Shop Online Today or call our friendly sales staff toll free (800) 853-2651. [ More Info ]
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.