What is this?

340 RR said
Thanks for all the info pat. I should be able to rebuild the original prop valve fairly easily. I'm gonna work on it tomorrow. The thing that might be a pain is flaring the brake line that goes to the passenger front caliper while the line is still routed all the way to that caliper. When I was taking that line off the prop valve, I had to break it off because the nut was too far seized. I traced the line and it's routed pretty nicely but it would be tough to get that line out and re-route a new one. I only took off like an inch from that brake line so I'm hoping I can flare it while it's still routed and connect it back to the prop valve after it gets rebuilt.

mine broke on the caliper side (see arrow)...I bought a short piece of line with fittings on both sides and bent the loop, then cut back the line on the car around where the red circle is, put a nut on it and flared it, then used a union like one of these to connect it up: Amazon.com you might be able to find a relatively accessible and straight section on your existing brake line to be able to do the same instead of remaking the entire line.

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