I'm losing enough to merit needing to check the fluid every two weeks or so, depending on how much I drive. The pedal feels fine until the fluid gets too low, as one would expect. I have absolute no drippage marks on my driveway.
Brake Fluid Leak, mystery source: 97 Civic
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By now, that thing would be flooding out elsewhere with the amount of fluid I've added over the last year. When I installed the last Master Cylinder, the booster felt like it worked perfectly and I didn't hear any slushing or noises to indicate fluid inside.
How do your brake pads look? Meaning are they new or almost worn out? If they are almost worn out then that's why your fluid level is low (if there are no leaks). I know it's an obvious thing to look out for but it can be overlook at times.
If there is brake fluid inside the brake booster then the brake master cylinder (primary piston seal) is leaking brake fluid. Since you are loosing fluid, I think your brake master cylinder is leaking brake fluid into the brake booster and the fluid is being sucked into the engine through the vacuum hose connection. Remove the brake master cylinder and check the backside, it should be completely dry. Also, try checking the bottom of the brake booster (try using a zip tie like a dipstick) for any brake fluid.
If there is brake fluid inside the brake booster then the brake master cylinder (primary piston seal) is leaking brake fluid. Since you are loosing fluid, I think your brake master cylinder is leaking brake fluid into the brake booster and the fluid is being sucked into the engine through the vacuum hose connection. Remove the brake master cylinder and check the backside, it should be completely dry. Also, try checking the bottom of the brake booster (try using a zip tie like a dipstick) for any brake fluid.
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Ive lost far more fluid over a long period of time that greatly exceeds the current pad wear so thats definitely not it.How do your brake pads look? Meaning are they new or almost worn out? If they are almost worn out then that's why your fluid level is low (if there are no leaks). I know it's an obvious thing to look out for but it can be overlook at times.
I did not consider that the vacuum line could be dispensing any potential leak out of tge booster. Although its unlikely that 2 rebuilt BMCs have also leaked, Ill still check the vacuum line for moisture and inspect the booster with your "dipstick" idea. Thanks for the suggestions.If there is brake fluid inside the brake booster then the brake master cylinder (primary piston seal) is leaking brake fluid. Since you are loosing fluid, I think your brake master cylinder is leaking brake fluid into the brake booster and the fluid is being sucked into the engine through the vacuum hose connection. Remove the brake master cylinder and check the backside, it should be completely dry. Also, try checking the bottom of the brake booster (try using a zip tie like a dipstick) for any brake fluid.