I've had my 48 8N since 1974. I've replaced the shut off 4 or 5 times. Every time they were basically junk right out of the box. Threads, jammed, shut off that the fitting would turn out before you could open the line, or leaking from many spots. Recently, the tractor would start and quit after a minute or 2. I did the leak down test suggested and found the gas would start OK and then quit flowing after a few seconds. Expecting the problem to be bad gas or rust gunk in the tank ordered and replaced both the tank and the shut off. The new shut off does not work. can hardly turn it and can not stop the extra fitting from leaking. Stripped out the threads with very little force. Checked the old tank. spotlessly clean and free of rust or gunk. The old shut off was somehow not opening, but the bulb was clean. So Now I have a fairly good used tank to sell and need to buy a new shut off that works or at least does nt leak. Where can a person buy one that works? By the way, over the years I came to the conclusion that when it works, never turn or touch the shutoff. I looked into my inventory and found 5 junk shutoffs.