Looks like I broke my brakes (help)

[98 SNAKE EATER]

OK, so I've been putting off replacing all my bleeder valves for some time now.

Never had any problems with my brakes, but figured I should get it done before my next brake service.

I got all four caliper valves from the dealer, but went with a Speed Bleeder for the LSPV

After hitting the beach trails over the Winter, the old ones were pretty seized up, so I had to break out the torch for a little quick heat and was able to get them loose

Thing is, I didn't have someone on hand to hold the pedal down, so it they most likely took in some air.

The new caliper valves went on fine, but the speed bleeder came up about 2mm too short and wouldn't seat properly before bottoming out

So I just took the old one, soaked it in some brake cleaner, ran a piece of wire through it and blew it out with compressed air.

Popped it back in and it I was good to go.

Did the usual 2 man bleed starting with the calipers furthest from the master and finally did the LSPV.

All was good until this morning when I noticed the pedal getting hard after a quick stop

If I drive for a bit and do a hard stop, it felt fine, but if I try to stop immediately after that, the pedal would get stiff and I wouldn't have any power brakes

So I came back to the shop, but I'm the only one here, so I used a vacuum bleeder.

Did the usual rounds for each caliper and finally the LSPV, but didn't see any visible bubbles in the line.

Then our shop manager showed up and I had him pump the brakes for another 2-man bleed.

We did it both with the engine off and then again with the engine running.

Good flow from each valve and again, no bubbles in the line.

Checked each wheel individually and each one holds and releases just fine.

Took her out for a test drive, but the pedal still gets stiff after the first hard stop

Is there sumthin I'm missing here?

 

[greentruck]

Maybe it's the booster coincidentally acting up after working on the hydraulics?

 

[98 SNAKE EATER]

I hope not.....

Those things aren't cheap

 

[98 SNAKE EATER]

OK, I pulled the vacuum hose and the intake end had a split right under the clamp.

It's a bit brittle, but I chopped off the split end and re-connected it.

Seems to have helped a little (at least for the first hard stab at the pedal), but still the same hard pedal after the second or third hit.

There are a few cracks throughout the hose, so I'm gunna order a new one, then bleed the brakes one more time on Monday before hunting for a new booster.

now that I think about it, I did have all the diffs locked while bleeding (I usually locked them up in the air in order to torque the lugnuts without putting weight on the wheels)

Would having the diffs locked (and ultimately, the ABS turned off) cause an issue with bleeding?

I doubt it since I got good flow from all 5 valves, but just curious

 

[tomcat]

Air in the line is not your problem, if there was air the pedal would be soft with the engine running. sound more like vacuum leak to the booster or the booster its self.

 

[98 SNAKE EATER]

Yeah, looks like that's where I'm headed

Just pulled the check valve and it checked out just fine.

Took the hose off and did a pressure check with some soapy water and didn't get any bubbles (still gunna order another one though)

Question:

Can the booster be replaced without pulling the lines off the master?

 

[NLXTACY]

I just did that a few weeks ago. There is a way to do it without taking out the ABS lines but honestly, remove the lines and make the 3-hour job into a 30 minute job. i WISH I just removed the lines first when I did it.

 

[98 SNAKE EATER]

I was looking at this page and it looks like they didn't mess with the lines, but for some reason, mine looks more cramped

http://www.4x4wire.com/toyota/maintenance/brakebooster/

 

[NLXTACY]

You have to push the MC so far forward to get the booster out that I was convinced that the tube would pinch at the fitting since it wasn't rotating. Once I cracked the fitting to allow the brake line to spin I finally said screw it and took off the lines. It cut the time way down.

 

[98 SNAKE EATER]

OK, followed the FSM to make sure the booster was the culprit and although it passed the "Operation Check", it didn't pass the "Air Tightness Check"

When I shut the motor down with the pedal depressed, after a few seconds, it just suddenly pushes back up with break leg force


My local dealer wanted $400 for a new one, but that was way too much cheese, so I just ordered a new OEM hose and as much as I hated to do it, I had VatoZone drop off a reman

I was able to R&R without removing any lines

The lines were flexible enough to give me more room than I needed


The hardest part for me was actually squeezing my fat arse under the dash to put the top left nut back on

I refused to take off the Cruise Control box, which would've made it much easier, but I'm too lazy (and stubborn) to walk all the way back to my tool box to grab a 10mm socket

All is well and the whole job took about 40 minutes

 

[RS6tofj80]

I've got a spare set of calipers I'm happy to give you for shipping costs... they were reman doen 2 years ago but I just repalced them again out of caution - my issue turned out to be a warped rotor....they're sitting in boxes ready to ship.

 

[98 SNAKE EATER]

My calipers are still in good order, but thanks for the offer


New hose just arrived....

Old one held pressure fine, but showed to

 

[98 SNAKE EATER]

A little update....

Started getting the same symptoms of a failing booster about a month ago

Pedal felt fine for normal driving, but got stiff about half way down and wasn't able to lock up the tires in a panic stop like it usually would

It passed both (a) and (b) operation checks as well as (a) air tightness check, but failed the (b) air tightness check as the pedal rises quickly after shutting down the engine

I had been meaning to replace the brake hoses with OEM extended lines to see if that would help, so I put those in yesterday and bled everything, but the problems still persists

Was gunna order a new check valve, but since I have lifetime warranty on the booster, I just had VatoZone send me another

Waiting on an OEM gasket for the master before swapping it out.....

 

[98 SNAKE EATER]

OK, the new gasket came in yesterday, but it was kinda busy, so I put it off until today....

The new booster looks pretty much identical to the one I put in last year except for a few things...

1) Instead of gray paint, the new one is powder coated black
2) Has a sticker that says BOSCH on it, even though it's stamped BENDIX like the old one
3) Has a different dust boot and filter on the rod
4) Check valve has a kink in the elbow


The swap was pretty much straight forward and took me about ~40 minutes just like last time, but this time around I had to dismantle the Blue Sea bypass switch and bracket for the winch solenoid

Now I'm able to lock up the 35's and get the ABS to kick in on dry roads again

 

[scrowley]

How much for AutoZone booster? I rebuild all my brakes components but the booster. My pedal kind of feels stiff on hard braking but not quite as drastic as you discribe. i def cannot lock up 37's ever. Not even close. Well in snow only. Maybe I'll just try one.

 

[98 SNAKE EATER]

How much for AutoZone booster? I rebuild all my brakes components but the booster. My pedal kind of feels stiff on hard braking but not quite as drastic as you discribe. Maybe I'll just try one.

List: $479.16
Shop Cost: $239.58
Core: $57.00

 

[Tapage]

Quite discount ...

 

[Tux318]

I too just replaced my booster. Pedal seemed normal, except for it got hard near halfway point. I could hear a whistle if I held the pedal down. Failed the airtight test....pedal would shoot up while holding it down at idle and shutting the engine off. Anyway, new booster did the trick.

I also decided to bleed the brakes just because. I found the lspv was leaking. I went ahead and replaced the MC, lspv, pads, rotors, rubber lines, rebuilt calipers, and bled it again. I did the entire brake system because I'm anal and she's 19 years old. Wow what a difference!

When I bled, I bench bleed the master and gravity bled everything else. Then I did a two man bleed. I took it out on gravel and engaged the abs, then two man bled again. Easy as pie.