Master Cylinder or BrakeBooster? Or both?
On my last trip, I started having issues with my brakes. After pressing the brake pedal and initially having brakes, it would then lose pressure and slowly go to the floor. It happened a couple time...
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Sounds like a failing Master Cylinder.
I've heard of the MC leaking and the Booster "absorb" the fluid up. Would fill up enough to reach the level of the vacuum hose, then the engine would "drink" it.
When we had the '83 E350, I replaced both with a lifetime warranted set from AutoZone.
Caution: Be sure if you're replacing MC or Booster, that the Booster's actuating rod mates properly with the back of the MC's piston. If some rebuilder used a piston with too deep a recess for the rod, then the booster can's actuate it. Even with a new "set" like I bought, it wouldn't hurt to separate the pieces and be sure the little threaded tip on the rod is adjusted correctly. There should be just a touch of clearance.
I've heard of the MC leaking and the Booster "absorb" the fluid up. Would fill up enough to reach the level of the vacuum hose, then the engine would "drink" it.
When we had the '83 E350, I replaced both with a lifetime warranted set from AutoZone.
Caution: Be sure if you're replacing MC or Booster, that the Booster's actuating rod mates properly with the back of the MC's piston. If some rebuilder used a piston with too deep a recess for the rod, then the booster can's actuate it. Even with a new "set" like I bought, it wouldn't hurt to separate the pieces and be sure the little threaded tip on the rod is adjusted correctly. There should be just a touch of clearance.
