Master Cylinder Float Switch...
 

After looking into why the Brake Warning light on my '85 keeps flickering, I saw that the fluid level sensor float had brake fluid trapped inside it. Obviously there's a crack or something allowing some amount of fluid to seep in and making the float not float so well. I've tried emptying it by placing it in various positions on the workbench and letting it seep out from wherever the opening that allowed it to seep in may be, but that's not working. I thought about drilling a small hole into the top of it to empty it out, then sealing the hole with a JB Weld-type epoxy, but even if that works there's still the original breach to locate and seal. It seems like an excessive and time consuming exercise to go through for something that could be lived with by pulling a wire connector at the cap to kill the indicator lamp and keeping an eye on the level the old fashioned way, but I'd like it to work as designed. I can't find the float/mesh assembly (or just the float itself) in the parts catalog here, so if anyone knows a source for one please chime in.

Don

Here you go: https://www.pelicanparts.com/More_Info/91135535100.htm?pn=911-355-351-00-M100

Part #: 911-355-351-00-M100

Thanks, Alex!
That part number is for a later year car, though it may indeed work. I since pulled the PET and found it's part# 911-355-420-01 so I called the local Porsche dealership and they can order it for $41 bucks and have it to me in a couple days. I subsequently entered the number into Google and it brought up an e-Bay listing for a used one at $18 bucks + $3.50 shipping so I went with that. I wish I would have checked all this out before posting this on the forum, but I'm not often the sharpest knife, so to speak. Thanks for your research nonetheless.

Don