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Can't find brake fluid reservoir...

Can't find brake fluid reservoir...

AnnieOakley

Jeeper
Posts
9
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Location
Great Falls, MT
Vehicle(s)
'75 CJ5 - no idea about all the details.
So... I feel like an idiot, and I have pictures because I feel like such an idiot. But I can't find the brake fluid reservoir in my '75 CJ5 .

Is it possible the the brake fluid just goes right into the master cylinder?
 
Don't know why it wouldn't let me attach more than one picture but here's the gist of what's going on under the hood
 
In your first picture you are looking right at the reservoir. In older vehicles the master cylinder and reservoir are the same part. Snap the heavy wire on the shinny (relatively) part either right or left and the cover will com right off, likly leaving the rubber seal in place or in the cover. Make sure to poke the rubber blatter part back up into the cap before replacing it. If you are new to this stuff, be carefull with brake fluid, it can be some nasty stuff especially to your paint.

EDIT: I just opened your second picture, looks like you've found the reservoir. You can fill the reservoir up with more fluid, but you have to ask yourself, "Why is my fluid low?" Usually there are two reasons for low fluid. First, you have a leak somewhere in the system, if so FIND IT, don't drive until you do. Second and probably more commonly, your brake shoes (Disk Brakes) are warn out and you need to replace them. The missing fluid isn't really missing at all, its in the caliper pistons. Before wisdom set in I am guilty of filling the reservoir to realize that my brakes needed new pads, when I opened up the cylinders for the new pads my nice new brake fluid would over flow on to the garage floor.
 
Last edited:
Ahh thank you! I had a feeling that had to be it.

Now for my second stupid question - if there is currently only fluid in one of the two compartments is that the way it's supposed to be or should they both be full?
 
We were both typing, I was adding content. Your front brakes and rear brakes have seperate compartments. This allows you to have brakes in at least one set of wheels in the event of a brake line failure. As I wrote above, your front brake pads likely need replacing. Do it before long or you will need new rotors as well. Not to worry if you've ground your rotors, they are relatively inexpensive and relatively easy to change. If that is the casae, you need to repack your wheel bearing too and it's time to learn how to do that. IT can be a greasy mess, but is esy enough to do.
 
You are a hero with a wealth of knowledge... Thank God people like you exist to answer questions for people like me. :)
 
Hero ... No .... glad to help .... Yes. ... We've all been where you are right now. :)
 
In my 8 i was having brake fluid sucked through the booster and into the engine and out the exhaust. It was not pretty. But as you have manual brakes I don't think that is your problem. Good luck.


Dain
 
If it looks like a duck and quacks like a duck, look for a duck first.
 
So instead of starting a whole new thread for this week's problem I figured if see if you guys had any guesses.

My inline fuel pump has a switch separate from the ignition so that I start it first, it sounds pretty loud, quiets down when it's good to go, and then I start my jeep. Usually that only takes about a minute if I'm driving her regularly. A couple of weeks ago I ran the fuel pump for ages, couldn't get it to start though and it never quieted down... I figured it was an old fuel pump and it wouldn't hurt to replace it anyways so I did, and she ran like a champ before the whole brake fluid incident... I went to go start her back up and now she's having the same problem.

I'm at a loss.
 
Inline pump with a switch-sounds like an electric pump. Is this in addition to a mechanical pump?
 
When your pump is loud there is no gas in it and then as it gets gas it quiets down. So when it doesn't quiet down it's not getting any fuel. Pumps work better when all they have to do is push the gas to the carb so it should be mounted so the gas from the tank has a siphon effect to the pump. I wonder why its been changed to a electric pump in the first place.
 
EDIT: I just opened your second picture, looks like you've found the reservoir. You can fill the reservoir up with more fluid, but you have to ask yourself, "Why is my fluid low?" Usually there are two reasons for low fluid. First, you have a leak somewhere in the system, if so FIND IT, don't drive until you do. Second and probably more commonly, your brake shoes (Disk Brakes) are warn out and you need to replace them. The missing fluid isn't really missing at all, its in the caliper pistons. Before wisdom set in I am guilty of filling the reservoir to realize that my brakes needed new pads, when I opened up the cylinders for the new pads my nice new brake fluid would over flow on to the garage floor.

I'm confused on the disk brake talk for a 1975 Jeep CJ. My '75 CJ has drum brakes all around. I was also missing the fluid in half of my reservoir caused by a leaking piston in the rear brake drum. The leaked fluid contaminated the brake shoes causing that brake to be 'sticky'. Since the Jeep was new to me, and I value braking ability, I replaced the pistons and shoes (with resurfaced drums) on all four wheels.

It also turned out that the brake master cylinder itself had a slow leak - replaced that too. It was only $24 at O'Reilly.
 
Sorry about the disk brake conversation. Drum brakes wear, but generally don't wear enough to move much brake fluid. Disk brakes will use a lot of fluid to fill the caliper cylinders and you can gauge pad wear by fluid use. Usually the back reservoir is for the front brakes (Not on your '75 or mine) so when I saw that one being low my mind went to disk brakes. Sorry for the misdirection with the type brakes you have.
 

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