1996 2.2L 5spd Legacy Brake issues / failure

[asparagus]

I just bought a 1996 Legacy Wagon 2.2L 5spd for my winter commuter car and had the following issue yesterday on the way home.

 

Left Boone after running errands in town

Drove the first 17 miles of my 23 mile trip home, ultimately parking car in a level lot and catching a ride home.

 

At mile 13 starts a 3 mile grade uphill

There was a light braking before the grade to slow from 40mph-35mph

About a mile up the grade, downshifted from 5th to 4th with no issue

Began to smell hot brakes within a mile of the shift, figuring it was from some of the traffic going downgrade

Continued to smell brakes and decided to park at the top of the hill at the first available parking lot

 

Front, left wheel was hot and smoking stinking of cooked brakes ... other 3 wheels fine and no smoke coming from under hood locations

Waited about 30 minutes for the wheel to cool off, started car to drive 300 yards across street and park in a different lot

 

Checked brake fluid level (full) and no signs of any leaks from anywhere

 

I noticed that the brake pedal traveling to the floor, even after several pumps, with the engine off, and even easier once the engine was running with the power assist.

Caught a ride home and left car to sit overnight

 

Returned this morning to see if anything had changed after sitting and cooling off to find no changes in lack of brakes or brake pedal engagement

 

No error codes are reporting on the dash

Clutch shifted cleanly all day, including the downshift going up the hill, engaging and disengaging as expected, all gears available with engine off or on

E-brake works

 

 

 

Thoughts on where to start?

[Rooster2]

Your left front brake pads have locked up on your rotor. I have had this happen, so I have seen this first hand. The brake caliper slide pins bind up from lack of grease lube, or rubber boot is broken, so rust forms around the pin. You apply the brakes, but the pads don't release from the rotor, and slide back as they should. The result is the pads stay applied at all times, heat up, and burn up the remaining portion of the brake pad.

 

The solution is fix the brake. It will require new brake pads, and also work to free the frozen slide pin, that the pad rests on. If slide pin cannot be freed up, then a replacement caliper is needed.

 

None of this is difficult if you want to do your own brake work.

 

Suggest you have your car towed home, or to a repair shop. Since all Subies are all wheel drive, you MUST have your car put on a flat bed tow truck to be moved. Do not have the car towed with two wheels rolling on the pavement. To do so will ruin the AWD system, and will be costly to be repaired.

 

Some guys on this forum do brake preventive maintenance work every 2-3 years on their Subies by regreasing the slide pins to preclude just the problem that you are having.

[Fairtax4me]

If the brake fluid isn't low and there are no obvious leaks its possible the fluid has boiled in the caliper/line and there is now air in the system.

 

That car has a hill holder which keeps pressure on the left front and right rear brake while you transition from brake to clutch to keep from rolling back when starting on a hill. If the lever for the hill holder gets sticky it will hold pressure on the brake while driving. The hill holder is on top of the frame rail on the drivers side below the master cylinder. Move the lever by hand and make sure it moves easily and returns to the open position. Spray some penetrating oil on the pivot for the lever if it feels like its sticking.

The hill holder is cable actuated by the clutch release lever. If the cable is adjusted too tight the holder may not fully release, and will keep slight pressure applied to the brake causing it to drag.

 

If you can't work on it in the parking lot, have it towed home on a flat bed.

 

Inspect the brake caliper slide pins. Make sure they slide easily. Try to compress the piston into the caliper and see if it is difficult. If it is, open the bleeder screw to release fluid while compressin the caliper piston. If it gets easier there may be a blockage in the hose or somewhere further up in the system, such as the hill holder mechanism.

 

If it's still difficult the caliper bore is rusted and is causing the piston to stick. The caliper will need to be replaced.

 

The brake fluid will need to be bled from the left front wheel at the very least.

If the fluid in the reservoir is dirty you should bleed the entire system to get all the nasty dirty fluid out.

[AdventureSubaru]

Good used caliper is about $20-$30 from a junkyard or auto dismantler. Easy job. Takes 30 minutes if there's not a ton of rust.

[asparagus]

Front brakes replaced all around (hoses, calipers, rotors, pads).

 

How do I kill the &&&&&&& hill holder?  I know it's likely out of adjustment slightly (still making slightest bit of contact), but I want to know how to remove the feature for people who can't drive stick shift.  Seems like it is overcomplicating the brakes system.

 

Can I adjust it the cable to the point it will never engage?  (If so, can someone send a pic with a wider field of view than the Haynes manual so I can find the adjustment nut)

 

If it's still rubbing after that, what needs to happen to eliminate the marble valve in the front brakes system?

 

Thanks.

[Fairtax4me]

Adjusting nut is on the cable end at the release lever. (Just under the clutch cable)

Just turn the adjusting nut back a few turns and that will loosen the engagement.

Its adjusted too tight if its interfering. It should never keep the car from rolling forward. It should only hold the car from rolling backward down a hill.

 

If you want to disengage it entirely just remove the cable from the release lever, then pull it back through the bracket on the bellhousing and push it off to the side where it can't interfere with the lever.

Edited September 13, 2015 by Fairtax4me

[asparagus]

The hill holder has been completely removed ... check valve / spring assembly / cable deleted with corrected plumbing to brakes.

 

 

I live in the mountains and have driven a number of other MT vehicles without hill holders ... the idea of a marble deciding if one of the calipers should remain engaged while shifting and traveling uphill in any gear freaks me out.

 

I think the reason the left, front brack seized in the first place was related to the hill holder check valve sticking / failing / misbehaving as I was downshifting (5th to 4th) on an incline after braking. 

 

It seems like you could trip the hill holder (even when working and adjusted properly) by engaging the clutch, using brakes (say to avoid a deer or really slow truck prior to having a window to change lanes), and downshifting prior to going further up the hill.  2-3 miles later you end up with a cooked left front brake system. 

[robm]

You are right, it should be possible to apply the hill holder when moving up hill by applying the brake and clutch simultaneously.  But it should release when the clutch is released.  IF it dosen't then there is something wrong with the adjustment or the HH.