In Reply to: 8N OEM Fuel Valve posted by Dean on March 15, 2023 at 14:55:06:
I wasn't aware of any leather washer on the Bulb. Be more specific please. There's a flat cork gasket on the Bulb between it and the glass jar and a rubber 'seal' on the Valve Stem, and that's it. On the Fuel Sediment Bulb, you only should pull the entire Bulb assmbly to clean the fine mesh screen on the top. The Bulb and tank use a 3/8" NPT thread so caution advised when R & R'g it. The only working/wear part is the Valve Stem. It should be the only part you need to replace with new. The stem has a rubber 'seal' on the shaft. It will wear and get chewed up from usage. Some new foreign-made suppliers use vinyl and this will deterioate faster than rubber. The Stem will create leaks when seal wears. There are three screens in the fuel system. Two are on the Bulb, one on the Carb, in the brass elbow fuel line inlet. The latter one is often neglected when having fuel blockage issues. The fuel inlet on the top of the Bulb Assembly has a fine-mesh, soldered on screen designed to filter debris from inside the gas tank before it enters the system. The Valve Stem, p/n APN-9194, should be the only part you need to purchase when 'seal' wears and begins to leak. It includes the stem shaft with a new seal, the knurled Open/Close Knob, and an 8-32 screw with a star washer that I advise to apply a dab of threadlocker so the screw doesn't loosen up and the knob falls off in the field. Fuel and Brake line thread size is a special industry standard; 7/16-24" UNS. The fuel line fittings, the Bulb inlet ports, and the Carb inlet elbow have these sizes and if you cross thread them or try to use a different thread, you will booger up the part. The Bulb is made of pewter or aluminum, and if cross threaded will be junk. The Valve Stem is a $6-$8 part. JUST8N's stocks them Other suppliers may charge more so watch out. It matters where you buy from.