Brake issues

[mike70kg]

Hey all,

On the way home from the parts store for a filter that ended up not fitting the chrome housing I have on the car (thanks for the tip on NAPA, Marc, but the filter ended up being too tall and just slightly too fat OD..) I was hearing some sort of noise that honestly sounded like I was making it up it was so difficult to place. I'm assuming now it was the front brakes - lost all braking power, thankfully sitting on an off-ramp.

I checked the reservoir, the lines, etc, all looked dry, no puddles on the road. Went to pop the passengers front tire off and the thing was screaming hot (now have a nice blister on the back of my right hand). I couldn't even touch the hubcap, lugs, or rim. The drivers side was warm, but I could get a hand on it.. Nothing glaring on the pass side, but took off the dust cap and steam came out of there. We'd had a problem on the 67 bug, ended up being the wrong bearings, but we couldn't even get down the street with those on it. After sitting on the side of the road for 15-20 minutes, the brake pedal worked its way back up and back to original pressure. Has anyone had this issue? I was driving for 10-15 minutes at highway speeds leading up to this. I'm considering just going all new up front, but would like to avoid that if possible.

[Marc]

First impression is that the brakes were probably dragging enough to boil the brake fluid. If just on one side I'd suspect a sticking caliper or bad flexhose, but do check that there's sufficient master cylinder pushrod freeplay. The pedal should move ~¼" before the pushrod contacts the M/C piston (~1mm play at the pushrod).
Have you noticed the brakes pulling to either side, either going down the road or upon initial application?

[mike70kg]

I have noticed the brakes pulling. It would pull to the right after hitting the brakes, but now that I'm thinking about it, the car was pulling to the right even without the brakes on as I was pulling off the highway. This is the first time that's happened. I think the end play is alright, but when I hit the brakes, I have to pull the pedal back with my feet to disengage completely. I'm used to it now, but suppose it was possible I didn't pull it back leading up to this point.

Must be interrelated - do you think the brake pedal return spring needs replacing?

[Marc]

Unless the return spring is broken/rusted away, it's more likely that the pedal cluster needs servicing. The brake pedal should move freely, there's nothing to restrain it other than friction or pebbles caught between it and the stop on the floorboard. A problem here would affect both sides equally, assuming everything else was in good condition.
Pulling to one side could be caused by one or more caliper pistons sticking in their bore (there are 2 in each caliper) or restriction in the flexhose. Old hoses tend to swell up inside, restricting flow and possibly blocking it completely when the pedal is released...the rubber can act as a check valve, only allowing flow to the caliper so pressure builds up that causes it to drag.
If the hoses look like they're original, they're long overdue for replacement so would be a good place to start. Replace them, rebuild the pedal cluster, bleed the brakes and see what symptoms (if any) remain.

[mike70kg]

Marc,

I checked the endplay on the brake pedal - looks good. Don't have the hoses yet, but will be replacing them when I get the chance and a driveway (currently in an apartment building, street parking only. This makes it quite a PIA to get to the car, back to the apt to take a look at things in proper light/dryness).

I got the pedal cluster out and cleaned it up; it seems to be in good shape. However, the brake pedal seems to be really tight while the clutch swings loosely, is this normal? It's been a while since I've had one out to look at, so can't remember if the swing on the brake is supposed to be tight.

[Marc]

The brake pedal should also move freely. Best to tear the whole cluster apart so you can polish things up and reassemble well-greased but you should at least use some penetrating oil (PB Blaster for example) and work it until free before you bother to reinstall the cluster.

[mike70kg]

Marc,

Just wanted to write in again (very belatedly - been a long two months) and say thanks for your help. I got the front rubber lines replaced and the brakes are in much better shape. They're still some pulling, and I think I may have cooked the bearings, but minor stuff in comparison to no brakes! I'll be looking further into those when the semester ends and I have an indoor spot.

-Mike