In Reply to: Fuel Valve Knob posted by Richard on December 06, 2018 at 06:57:26:
The Sediment Bulb Assembly Fuel Valve Knob falling off has been a problem for a few decades. Seems it never happened on originals. When I was losing them mowing grass with my 8N after the 2nd time or so I got wise and started applying a dab of Threadlocking Compound on the 8-32 screw when I installed it. The Fuel Valve Stem, p/n APN-9194, is the only wear/working part on the Sediment Bulb. There is a rubber 'seal' on the stem that will eventually get chewed up and worn out and thus cause leaks. It is a $6 part and is the only part that needs to re be replaced. You do not need to replace the entire Sediment Bulb Assembly if leaks develop unless the inlet or outlet port threads get stripped out. That is another problem because many do not realize they use a special thread size -7/16-24 used on brake and fuel lines. Attempts to retap with the wrong size tool or by crossthreading at installation mucks it up and will also cause leaks. Avoid Teflon tape for a 'fix'. Do the job right the first time. Do you want to be guessing if your fuel system will leak? Threadlocking Compound can be purchased at any auto parts supplier. It will permanently keep that screw from falling out. There is no need to ever remove it. When the fuel valve stem eventually fails from a bad/worn seal, remove it, purchase a new one, and repeat Threadlocking process and reinstall it.
VALVE STEM KNOB:
FORD TRACTOR SEDIMENT BULB ASSEMBLY w/ VALVE STEM:
VALVE STEM 8-32 TAPPED HOLE FOR KNOB SCREW:
FORD TRACTOR SEDIMENT BULB VALVE STEM – SOLUTION FOR LOSING KNOB: