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General Information => Troubleshooting => Topic started by: shwartzbewithyou on April 26, 2006, 07:27:18 pm

Title: Master cylinder reservoir leaking suddenly
Post by: shwartzbewithyou on April 26, 2006, 07:27:18 pm

I lost brake pressure today at a stop light so I pulled into a gas station and checked and I have a massive leak where the reservoir meets that master cylinder.  I looked on all the parts websites and they sell a grommet for $2.00 or so each.  Is this all that holds the reservoir onto the master cylinder?  Because I wiggled the reservoir and it was loose and it leaked worse when I moved it.
So I'm just checking, is something under the reservoir broken or do I just replace the grommets and press it back into place?

Title: Master cylinder reservoir leaking suddenly
Post by: wyldman on April 26, 2006, 07:48:01 pm

The master cylinder reservoir musthave broken,as the seal rarely fails.

Try to pop the reservoir out and see what you find.

Title: Master cylinder reservoir leaking suddenly
Post by: shwartzbewithyou on April 27, 2006, 05:50:06 am

I will but I have to drive the car on Monday.  So that means I take it apart Saturday, and fix either Saturday or Sunday.  Yikes.  I hope I get parts in time.

Title: Master cylinder reservoir leaking suddenly
Post by: TDForNow on April 27, 2006, 10:10:55 am

Yes, those seals are all that hold the reservior in. There's no pressure there, just gravity and return. The (@1/4") nipples molded in to the bottom of the res. snap into the grommets on the master cyl. They're plastic just like the res. and can break easily if aged.

Title: Master cylinder reservoir leaking suddenly
Post by: shwartzbewithyou on April 30, 2006, 07:08:01 am

So I pulled it off and found the the problem is a little bit more difficult to fix than I thought.  It's the top of the master cylinder that's crusting away in it's old age.  So I had clean it up and hope for the best.  I pulled off the grommets and the one tore which sucks because I couldn't get new ones on such short notice.  So out came the gasket maker.  I cleaned up the top of the master cylinder with some rough sandpaper (oddly enough I can't find a file when I need one), and then spread some more gasket maker on the underside of the grommets.  I placed the grommets back in and let them sit overnight before puting any real pressure on them.  The next day i put the reservoir back on and put a large gear clamp over the top of it to hold pressure down on the gasket maker.  It's holding completely dry the next day after a couple of drives.  

So far so good.

I know the pro's on here are dissapointed in me, get over yourselves, it's a temp fix. :lol: