Strange thing I noticed: Brake fluid on the top of the Master Cylinder cap. I looked and sure enough saw a pin hole sized air bubble. Anyone have cap for sale or know where to get one? Thanks.
Jim
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Strange thing I noticed: Brake fluid on the top of the Master Cylinder cap. I looked and sure enough saw a pin hole sized air bubble. Anyone have cap for sale or know where to get one? Thanks.
Jim
Unless I'm mistaken there is brake system pressure under the cap when the brakes are applied. I don't think solder or JB Weld would be a proper repair.
If there is one pin hole how long before another shows up. I think a new cap, or good used cap, would be the proper repair.
Good comment. Perhaps the ultimate solution would be to get a new duel reservoir master cylinder. Brakes are a vital safety feature with no room for error. Thanks Matt. JohnQuote:
Originally Posted by Matt Cashion
P.S. I think White Post Restorations could hook Jim up with whichever solution he chooses. Jds
I found a good used cap...I think. The emergency brake is working correctly!!! (ha ha intended). I probably will eventually go with a modern dual master, but I just got it so I'm sorting things out. I did actually adjust the e brake after lubing the system. Brakes, they are NOT overrated!
Most brake system reservoirs are vented, either through the cap or somewhere else, so that atmospheric pressure can act on the fluid in the reservoir and a vacuum does not develop as fluid is drawn from the reservoir into the master cylinder cavity. Therefore, a small hole in the top of the cap would normally not be an issue unless the reservoir is overfilled. I would expect the real fluid level would be at least 1-1.5" below the top of the cap.
Unfortunately, my car is away having a grille hockey stick bring ground, polished, and rechromed for a better fit so I can't look to see if the cap itself is vented and the height of the cap versus the reservoir level..
Larry
The cap is vented, otherwise the system would not function properly. If brake fluid is coming out at the cap, the compensating valve may be no more tight: it closes the fluid path between the reservoir and the hydraulic cylinder during a brake application.
The cap is vented by a pin hole? Makes sense. I did fill it to the top when I got it. Perhaps I made a mistake, it's possible. I was due to make one! Thanks for help.
Exactly, a pin hole. The master brake cylinder is like a radiator: don't fill it up to the top!
Thanks,I now a spare cap with.... a pinhole vent!!! Live and learn.