Front Master Cylinder Reservoir Empty
Thread Starter
Cruising
Joined: Nov 2020
Posts: 10
Likes: 1
Front Master Cylinder Reservoir Empty
Hey all,
I recently tried taking my car (76 350 auto) out after having it parked for about a month and a half, but when I started the car the brake pedal went completely mush and straight to the floor. I checked the master cylinder and the front reservoir was completely empty and the rear one is full. I had brake work done last year swapping out the rotors, and calipers, checked the lines and can't find any obvious leaks. Any idea as to what could be happening? I saw similar threads where the rear reservoir was dried up and leaking into the booster, so could that be happening with the front one? Thanks in advance guys!
I recently tried taking my car (76 350 auto) out after having it parked for about a month and a half, but when I started the car the brake pedal went completely mush and straight to the floor. I checked the master cylinder and the front reservoir was completely empty and the rear one is full. I had brake work done last year swapping out the rotors, and calipers, checked the lines and can't find any obvious leaks. Any idea as to what could be happening? I saw similar threads where the rear reservoir was dried up and leaking into the booster, so could that be happening with the front one? Thanks in advance guys!
Last edited by Ltstevens76; Nov 25, 2020 at 12:46 AM.
Race Director
Joined: Nov 2006
Posts: 13,246
Likes: 7,837
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
front reservoir empty can only only mean one thing. a leak in the front brakes. a hole in a line or a bad caliper piston seal.
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,137
Likes: 4,248
From: US-PNW
Not likely as the only way to drain the front into the booster is to go past the rear reservoir's piston seals. If that were the case you'd have both empty. The only way to drain the front without the rear being affected is a leak in the front lines somewhere.
Thread Starter
Cruising
Joined: Nov 2020
Posts: 10
Likes: 1
Last edited by Ltstevens76; Nov 25, 2020 at 01:07 PM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If the caliper didn't leak in the first 100 miles, it will never leak...because of the caliper. Seals could be bad or no assembled properly. But it's very unlikely to be a caliper-only issue.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Melting Slicks
Joined: Mar 2010
Posts: 2,270
Likes: 375
From: Randolph nj
the castings are so bad where the lines go in your better off cleaning them up yourself with a dremel to get them flat then use a slightly thicker copper crush washer to take up any voids
also I would NOT bring the car back to the same place it might not be there fault that the castings are crap but they really should have inspected them before they used them ,, I have seen cars where they totally forgot the crush washers ,, or they got the lines with the wrong ones and used them anyway
also I would NOT bring the car back to the same place it might not be there fault that the castings are crap but they really should have inspected them before they used them ,, I have seen cars where they totally forgot the crush washers ,, or they got the lines with the wrong ones and used them anyway
Last edited by forman; Nov 26, 2020 at 03:08 PM.
