Question about master cylinder fluid levels?
Thread Starter
Racer
Joined: Nov 2006
Posts: 310
Likes: 0
From: Oak Park IL
Question about master cylinder fluid levels?
been having problems with my brakes and looked over the system and have seen no leaks so I popped the master cylinder and noticed that the chamber closest to the firewall was empty is this normal?
Burning Brakes
Joined: Oct 2006
Posts: 1,006
Likes: 28
From: Lutz Florida
No! Both reservoirs should be full to approximately 1/8th inch from the top of the master cylinder. The front reservoir is for the front wheels, the back reservoir is for the back wheels. I think you may need to rebuild or replace you master cylinder. The fluid could be leaking into the brake booster, thats why you don't see a leak. You need to check the whole system to see where that fluid went. Check under the booster and all lines and calipers. With a dry reservoir you are taking a chance driving the car - definitely not safe for you or anyone else on the road near you.
Instructor
Joined: Jan 2006
Posts: 134
Likes: 0
From: Western Burbs of Chicago Illinois
That's a bad thing. Both should be full. Fill it up, pump the brakes a few times. If the pedal starts to firm up, but still mushy, you have air in the lines.
Check the calipers for leaks. Before you do ANY pumping, use some brake cleaner and some clean rags and clean off the calipers and various brake line connections.
Then add fluid and pump the brakes. If someone is working with you and they're watching the calipers for leaks, WEAR eye protection. It may seep out slightly or squirt out. I had a line that seeped slightly while pumping the brakes
If that's the original master cylinder, replace it. I had a so much rust and crap in my MC, I could have bled til the cows come home and never get clean fluid. I changed the MC and bled the brakes and have had clean fluid since.
Good Luck
Check the calipers for leaks. Before you do ANY pumping, use some brake cleaner and some clean rags and clean off the calipers and various brake line connections.
Then add fluid and pump the brakes. If someone is working with you and they're watching the calipers for leaks, WEAR eye protection. It may seep out slightly or squirt out. I had a line that seeped slightly while pumping the brakes
If that's the original master cylinder, replace it. I had a so much rust and crap in my MC, I could have bled til the cows come home and never get clean fluid. I changed the MC and bled the brakes and have had clean fluid since.
Good Luck
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Safety Car
Joined: Jun 2004
Posts: 4,652
Likes: 80
From: Lakeland Florida
Hello,
This is still part of your earlier thread question about having brake problems. Both bowls should be full. If you fill up the bowls put the cover back on before you pump the brakes. If not you may find that this can shoot a geyser of brake fluid over your engine and/or fender.
The empty brake bowl may be one of the reasons you had brake problems. If you just bought the car you may not have had time to investigate the full problem. Fill the M/C with fluid, replace the cover, and pump the brakes to get the fluid to the rear calipers.
Check the level of the M/C from time to time. I am thinking you want to find out if one of the rear calipers has a leak in it, which is why the M/C was dry.
Now if the bowl was dry then you will ultimately have to pull it out to do a bench bleed of the cylinder anyway. And if you do that, consider a replacement unit instead. If you are not sure of the age of the system, if the M/C is bad or leaking, and face other problems, then a replacement unit may make sense.
And welcome to the "WHILE I AM AT IT" part of Corvette repair. You might as well replace some other components as long as you are beginning to take apart some of the brake system.
kdf
This is still part of your earlier thread question about having brake problems. Both bowls should be full. If you fill up the bowls put the cover back on before you pump the brakes. If not you may find that this can shoot a geyser of brake fluid over your engine and/or fender.
The empty brake bowl may be one of the reasons you had brake problems. If you just bought the car you may not have had time to investigate the full problem. Fill the M/C with fluid, replace the cover, and pump the brakes to get the fluid to the rear calipers.
Check the level of the M/C from time to time. I am thinking you want to find out if one of the rear calipers has a leak in it, which is why the M/C was dry.
Now if the bowl was dry then you will ultimately have to pull it out to do a bench bleed of the cylinder anyway. And if you do that, consider a replacement unit instead. If you are not sure of the age of the system, if the M/C is bad or leaking, and face other problems, then a replacement unit may make sense.
And welcome to the "WHILE I AM AT IT" part of Corvette repair. You might as well replace some other components as long as you are beginning to take apart some of the brake system.
kdf
Thread Starter
Racer
Joined: Nov 2006
Posts: 310
Likes: 0
From: Oak Park IL
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Thread Starter
Racer
Joined: Nov 2006
Posts: 310
Likes: 0
From: Oak Park IL
Clarification
Let me start by telling you how this happened...
I purchased the car last July but really have not driven it because I've been changing out the carb, headers & exhaust and gutting the interior the brakes have never been that great. Last Saturday I was taking her out for the first time and the brakes were working ok when all of a sudden they stopped working. I tried pumping and could not get anything out of them so I carfully put her back in the garage very tricky since she is an automatic, didn't look around to see what might have caused the problem because the wife was standing there with you know tha angry look
like I should be working on something other than the car. So I went in and tiled the bathroom which is a weekend project so the car sat until Monday night when I went out to open the Master Cylinder and noticed that there was no fluid in the rear chamber so that is where I am at at the moment. Sorry I know this is all basic stuff so go easy on me I am new to auto maintenance and need to sometimes double check things with others like all of you so I appreciate your patience and understanding.
Thanks.
I purchased the car last July but really have not driven it because I've been changing out the carb, headers & exhaust and gutting the interior the brakes have never been that great. Last Saturday I was taking her out for the first time and the brakes were working ok when all of a sudden they stopped working. I tried pumping and could not get anything out of them so I carfully put her back in the garage very tricky since she is an automatic, didn't look around to see what might have caused the problem because the wife was standing there with you know tha angry look
like I should be working on something other than the car. So I went in and tiled the bathroom which is a weekend project so the car sat until Monday night when I went out to open the Master Cylinder and noticed that there was no fluid in the rear chamber so that is where I am at at the moment. Sorry I know this is all basic stuff so go easy on me I am new to auto maintenance and need to sometimes double check things with others like all of you so I appreciate your patience and understanding.Thanks.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Racer
Joined: Jun 2004
Posts: 474
Likes: 0
From: Moncks Corner South Carolina
Man, I thought I was the only one with this problem. I can't get my car finished because of the dreaded weekend projects either.