My daily bomber has developed a nagging problem. It seems to "eat" about a 1/4 cup of brake fluid a week, yet I can't seem to figure out where its going. I've bled the brakes repeatedly and can't seem to locate a source of leakage. The brake pedal will also slowly sink to the floor if stopped for more than a couple minutes or so. But if I let off the brakes and press them back down, I magically have pedal pressure again.

Just another annoyance on the list . . . but I can't really complain since the car has 236k miles (that I know of), I got it for free, I've put 30k miles on it within the past 15 months and have only had to put about $200 into it including registration fees.

EDIT: sorry I just realized I posted this in the wrong forum . . .

 

Its going into the brake booster, if you cant find any other leaks. I'd just replace them both.

 

If it's not leaking out anywhere visible then Brake Booster would be my bet too... you've checked the caliper piston seals for leaks, right?

Christian

 

None of the calipers seemed to be wet/leaking when I had the wheels off. The sinking brake pedal would be a symptom of a bad brake booster though, right?

I really only have to make the car last another month or two as the wife and I will be picking up a new daily driver. I'm just debating whether or not to tackle the brake problem with the bomber or just keep her topped off with brake fluid. It leaks oil, tranny fluid, antifreeze and gas (if you top off the tank), so may as well drip brake fluid too. The hole in the b-pipe, rust-hole ventilation/AC and bald tires are charming too . . . but dammit I love the little beast.

The car is an 86 Volvo 240DL Wagon by the way . . . or as I call her "Brick."

 

the sinking pedal is most likely your MC going bad. mine would sink under very light (but steady pressure), and seemed to happen more in the summer, or when the car was hot. new MC fixed it.

also, check the rubber seal on the reseviour cap. mine was chunked up a bit, and the cap didn't make a complete seal, so fluid would leak out the top. Although I did find evidence of the leakage, so its probably not your problem.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bull &raquo;</TD></TR><TR><TD CLASS="quote">None of the calipers seemed to be wet/leaking when I had the wheels off. </TD></TR></TABLE>

Did you take the calipers off though?

 

Honestly I've not had the calipers off since I put rotors and pads on it about 10 months ago.

 

I'm with the MC/Booster crowd.

And yo should fix it - it's a safety issue - and the MC/booster are usually pretty easy to fix.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Crack Monkey &raquo;</TD></TR><TR><TD CLASS="quote">booster are usually pretty easy to fix.</TD></TR></TABLE>

Unless U have a 93 accord :throw **** around garage:

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Crack Monkey &raquo;</TD></TR><TR><TD CLASS="quote">I'm with the MC/Booster crowd.

And yo should fix it - it's a safety issue - and the MC/booster are usually pretty easy to fix.</TD></TR></TABLE>

I went through this with an 84 prelude back in college. Weirdest thing.

Finally after a couple weeks I filled the brake booster with brake fluid, and started sucking fluid into a vacuum hose. SMOKE SHIELD!! I still didn't understand where it was coming from, since I had so many holes in my exhaust, so I kept it up until I got some fluid to spray out of one of those holes.

Me being particularly dense, I spent some time trying to figure out, how did I get brake fluid INTO my exhaust, if I can't even see where it was dripping into my exhaust? That's the day I learned how a brake booster really works, and why all those vacuum lines were running all over the engine bay.

A Brake MC rebuild kit cost me ~$10. Probably up to $20 now, but it wasn't hard on that car.

 

My track car was eating brake fluid with no sign of where it was going. I discovered that the MC had gone bad and was leaking when I got on the brakes heavily. This resulted in missing brake fluid but no drips in the garage.