Brake pressure regulator rebuild?

[Swaggoner]

Has anyone

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successfully resealed the brake pressure regulator (951-355-305-01), which is attached to the front of the master cylinder? Mine has a very slow leak and I’m 100% certain it’s originating where the regulator screws together. Pelican is asking over $1000 for one! Aftermarket is close to $400.

[Tom]

I've never rebuilt one, or know of anyone who has. That said, if it is leaking anyway, not much risk taking it apart and seeing if a new seal or something fixes it. With companies like McMaster, Zoro, Graingers, etc. plus the entirety of the internet, you can almost always find just the right seal, washer, o-ring, etc. Last week, my beloved coolant system pressure tester stopped holding pressure. With nothing to lose, I disassembled it and found 4 little o-rings inside, one of which had failed. I measured it, got a bag of 50 from McMaster for $8, and it works like new again.

[stitch2k1]

There's a post buried on the r/944 subreddit about this, and how to convert the 18 bar one to a 33 bar one. Maybe from 6-8 months back?

[Swaggoner]

Thanks all. Searching reddit now...

[stitch2k1]

Recalling now there might have been a mistake with the guy accidentally losing some info. I don’t know if moderator logs go that far back but if it’s missing I can take a look.

(I am an inactive mod on the subreddit)

[Swaggoner]

Update...
Figured I had nothing to loose, so I broke open the regulator. Needed heat to soften the thread lock/sealant, but it finally released. Regulator had a bit of sludge, but no obvious problems. Replaced the small o-ring, put it back together and so far, 75 miles with no leaks!

[Tom]

Awesome! Great save. Was the o-ring just an off-the-shelf part?

[Swaggoner]

It was. Got a box of assorted sizes from Harbor Freight.

[dr bob]

Thanks for sharing this! I have a few different versions in my spares drawer that I've been accumulating but yet to test in service. Knowing I can take them apart for cleaning and inspection/refurb is awesome!