Jack - Thanks for the explanation on how these master cylinders work. That would explain why the fluid leaked out. The kit that Harmon sells is the one for the Kelsey-Hayes power unit. I just spoke to them a few minutes ago. Their complete kit is for both the p/b unit and the master. Here's the link to their kit: https://www.parts123.com/parts123/yb.dll?parta~partsort~1~cadfffkz~~20 Ron _____ From: Jack Boyle [mailto:jackcboyle@xxxxxxxxx] Sent: Tuesday, June 12, 2018 9:29 AM To: 'Ron Waters' Subject: RE: [Chrysler300] 1955 Power Brake Booster and Master Cylinder My late father was an expert on these and rebuilt one that I have in my stash. Usually when somebody has a '55 rebuild kit is not for the Kelsey-Hayes unit but for a traditional piston unit that was dealer installed on many cars. The KH unit uses a rod going through donut seals to displace fluid rather than a piston pushing a column of fluid. If, when you separated this unit's components, the stainless steel rod came out of the donut seals that would let the fluid out. I have struggled with my '55 brakes for years trying to get them up to modern/freeway needs. So I replace the KH unit with a safer double cylinder unit. I think the guy in Minnesota (he advertises everywhere) is the only source for kits for this unit. I do have an NOS kit but the rubber is so old.. ..Jack From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of 'Ron Waters' ronbo97@xxxxxxxxxxx [Chrysler300] Sent: Tuesday, June 12, 2018 7:56 AM To: Chrysler300@xxxxxxxxxxxxxxx Subject: [Chrysler300] 1955 Power Brake Booster and Master Cylinder Hey Everyone - I have a non-operating 1955 power brake booster. This is a one-year-only setup that is found on the C300 as well as other Mopars of that year. I removed the assembly from the firewall for repair. When I separated the master cylinder from the booster, brake fluid poured out of the rear bore of the master. There was also some brake fluid inside the rear of the booster. I was told that that was correct due to the design of the setup. I'm scratching my head on that. Any thoughts on this ? Side Note: The rebuild kit for the power brake unit is available from Harmon Classic Brakes (https://harmonclassicbrakes.com/). Ron _____ <https://www.avast.com/antivirus> Avast logo This email has been checked for viruses by Avast antivirus software. www.avast.com <https://www.avast.com/antivirus> [Non-text portions of this message have been removed] ------------------------------------ Posted by: "Ron Waters" <ronbo97@xxxxxxxxxxx> ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to https://groups.yahoo.com/neo/groups/all/manage/edit For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylang ------------------------------------ Yahoo Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: Chrysler300-digest@xxxxxxxxxxxxxxx Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo Groups is subject to: https://info.yahoo.com/legal/us/yahoo/utos/terms/