Toyota Corolla 94 Sticky Brakes when engine is hot, what could be the problem?

[dhunted2000]

Hi! I have a corolla 94 Big Body & brakes are sticky, we already repaired the master with a brake kit, repaired calipers & brake hose and still sticking, I separated the master cylinder brake from the booster and still sticky, then I tried bleeding from the master cylinder itself and the brakes are OK, this only happens when the engine is already hot.Thanks

[theshepherd]

You mean, na-stuck up ang brakes sir kahit hindi mo apakan? Harap o likod or both? Kung harap, Baka yung caliper piston ang may problema sir. Since yun ang tumutulak sa brake pads para maipit ang brake discs.

Peace out!

[dhunted2000]

theshepherd

Yes sir, stuck-up ung front brakes lang, maski hindi tapakan and sobrang init nung disc (tunaw ung sample plastic na napulot ko.. lol). I wonder kung caliper piston and may problema, bat nung tinanggal ko ung master cylinder sa booster and nagbleed ako dun sa master cylinder mismo eh lumuwag na ung preno, as in maitutulak ko na cya...

[Vootlog]

Baka restricted na ang mga brake hoses at kapag uminit na expanded ang loob barado na hind makabalik ang pressure ng brake fluid kaya stuck up siya.

[dhunted2000]

Baka restricted na ang mga brake hoses at kapag uminit na expanded ang loob barado na hind makabalik ang pressure ng brake fluid kaya stuck up siya.

Sir, meron po bang definite way para malaman kung ung brake hose po ang may problema?

thanks

[LN106G]

Its your brakemaster that has a problem. The repairkit you used is possibly NOT identical to the OEM. Or your mechanic adjusted the pushrod in the hydrovac (which by all means should NOT be adjusted) because of the different repair kit. Once these are touched, it is a guarantee that your brakes will stick. Replacing the repairkit requires that the replacement kit should be identical in all aspects especially the recessed part where the pushrod will rest. The pushrod in front of the hydrovac (this is the one between the brakemaster & the hydrovac) should NEVER be touched.

It could also be that your mechanic did all the right moves, however, the bleeding of your brake system is improper & inadequate...

Defective brake hose will rarely give a problem to both wheels....

[dr. d]

but when did the problem arise? before the repair, or after? if after, it's likely something wrong was done... in-appropriate repair kit... wrong adjustment (yeah, the pushrod clearance; it's my favorite, because of previous experience.. it's also probably the easiest to remedy..). the hydrovac and the master cylinder actually are designed as a matching set. you can't mix and match them, because the pushrod clearance will change..
yes, as ln1 says, improper bleeding is also a suspect..

btw, how long have you had that car?

[dhunted2000]

but when did the problem arise? before the repair, or after? if after, it's likely something wrong was done... in-appropriate repair kit... wrong adjustment (yeah, the pushrod clearance; it's my favorite, because of previous experience.. it's also probably the easiest to remedy..). the hydrovac and the master cylinder actually are designed as a matching set. you can't mix and match them, because the pushrod clearance will change..
yes, as ln1 says, improper bleeding is also a suspect..

btw, how long have you had that car?

Thanks to everyone for helping....

I actually bought this car from my cousin last July this year and they told me it's just sitting there for almost 8 months w/o them using it, so the mechanic towed the car and they told me that there are no brakes. so they repaired it using a kit. after, a day I took the car out and went for a test drive after a few kms it actually felt like the car was dragging something and it stalled so i told the mech bout the problem and a saw them make some adjustment to the pushrod. seems to work out but then again after a few kms again it happened.

here's what happened to the car recently :

1. Towed the car without breaks ( just handbrakes working ).
2. Repaired the master cylinder using a kit.
3. Now i have sticky calipers (both, you cannot rotate the wheels and very hot) ( but rear brakes are fine and normal temp ).
4. Opened the both calipers and master cylinder(again), bled, checked the brake hose, the mechanic said both are still OK.
5. While the disc are hot, we separated the MC from the booster, caliper still sticking.
6. Bled from the MC itself (while separated from booster). caliper lets loose of the wheels and can be rotated w/o much effort ...

during cold start, the brake pedals seems normal. after a few minutes of idle and normal driving. pedals becomes hard.

[raycon_24]

double check mo yung brake caliper at piston cup baka may scouring na due to corrosion kaya di na bumabalik, dapat kasi smooth ang bore ng brake caliper at yung piston cup, flash out mo rin brake fluid...

[LN106G]

Ask your mechanic if the repair kit he used is identical to the one he took out. Ask him also if he adjusted the pushrod in front of the hydrovac. If he did this things, you have to redo the repair. By experience with many cars of different brands, once you touch the adjustment of the said pushrod, you mess up your brake system. Few mechanics truly understand the physics of the hydrovac-brakemaster setup. The usual scenario is like this: they take out the leaking old repair kit, send their "boy" to the nearest suking auto supply and buy the replacement repair kit. If the most identical repair kit is unavailable they buy the "nearest" identical kit to save time then do the "patch-up" job back in their talyer ( this is where the unwanted adjustments are done). This is also the start of your headache...

Also if your front wheels stick again, just release the bleeder plug on your caliper to relieve the unwanted pressure. With your predicament it is not advisable to bleed your brakemaster as this can introduce unwanted air packets in your system thereby compounding your problem further...

Scored brake cylinders will not give you sticking brakes on both wheels simultaneously. I doubt this, since you mentioned earlier that you cleaned and changed(?) the caliper kit.....

Cheers!

[dhunted2000]

Ask your mechanic if the repair kit he used is identical to the one he took out. Ask him also if he adjusted the pushrod in front of the hydrovac. If he did this things, you have to redo the repair. By experience with many cars of different brands, once you touch the adjustment of the said pushrod, you mess up your brake system. Few mechanics truly understand the physics of the hydrovac-brakemaster setup. The usual scenario is like this: they take out the leaking old repair kit, send their "boy" to the nearest suking auto supply and buy the replacement repair kit. If the most identical repair kit is unavailable they buy the "nearest" identical kit to save time then do the "patch-up" job back in their talyer ( this is where the unwanted adjustments are done). This is also the start of your headache...

Also if your front wheels stick again, just release the bleeder plug on your caliper to relieve the unwanted pressure. With your predicament it is not advisable to bleed your brakemaster as this can introduce unwanted air packets in your system thereby compounding your problem further...

Scored brake cylinders will not give you sticking brakes on both wheels simultaneously. I doubt this, since you mentioned earlier that you cleaned and changed(?) the caliper kit.....

Cheers!

Thanks for the help....

we'll try to buy another MC repair kit and post any updates....

[pdspd]

Based on my personal exerience.Check vacuum leak on brake booster/hydrovac.Also check pushrod clearance between brake booster and brake pedal.Simple DIY is check/adjust brake pedal freeplay(1/2 inch).then start engine for a while.pump the brake pedal for a few times then press/hold the brake pedal.then turn off the engine .if the pedal moves slightly(2 inches max) downwards,thats normal.but if it still holds after turning off d engine,brake pedal adjustment too tight or possible brake booster defect.

[dhunted2000]

Based on my personal exerience.Check vacuum leak on brake booster/hydrovac.Also check pushrod clearance between brake booster and brake pedal.Simple DIY is check/adjust brake pedal freeplay(1/2 inch).then start engine for a while.pump the brake pedal for a few times then press/hold the brake pedal.then turn off the engine .if the pedal moves slightly(2 inches max) downwards,thats normal.but if it still holds after turning off d engine,brake pedal adjustment too tight or possible brake booster defect.

thank you sir,

i will take your advice and i'll post the result asap

[tip_tipid]

actually, the push rod that controls the action of the hydro vac is the one connected to the brake pedal. The secondary push rod on the master brake cylinder should be free to fully rest on it's own stopper when brake is not applied. Normally, there are two separate cylinders inside the brake master, which have individual springs to push the cylinders back when brake is released. also there is a stopper for the inner cylinder so that it will not slide beyond into the outer cylinder area. hope the explanation helps.
There is also a separate brake force divider.

[dr. d]

well, replacement of the brake master cylinder certainly looks like the faster (but more expensive) way out.. magkano bang bagong master ngayon?

[jick.cejoco]

Google Image Result for http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0900c152/80/09/2a/86/medium/0900c15280092a86.gif


Google Image Result for http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0900c152/80/09/2a/85/medium/0900c15280092a85.gif

[jick.cejoco]

you can use a similar fabricated tool to measure the pushrod length in relation to the primary piston cavity to make the correct adjustment





http://alldatapro.com/alldata/PRO~V3...24801/85063167

http://alldatapro.com/alldata/PRO~V3...24801/85063168

http://alldatapro.com/alldata/PRO~V3...24801/85063169

[jick.cejoco]

check your filler ports and compensating ports of the master cylinder, they can be seen through the master cylinder plastic reservoir or for the secondary filler and compensating port, you might need to remove the reservoir or the feeder hose to be able to inspect and clean these two ports.

[dhunted2000]

thanks guys for the help...

we'll try to open the master cylinder again as well as the brake hose.....

[X-isle]

Kamusta na yung brakes mo? Can you post any of your results and was the problem solved?

I have also been experiencing somewhat similar problem with this similar model of Toyota Corolla.

On my end though it usually happens when I have been on a "Stop and Go" traffic for a long time. What happens is pag apak ko on the brakes ever so slightly bigla siya mag brake as if you suddenly fully stepped on it.

And then once you start to move you'll feel the "Drag" but then if you continue moving nawawala yung drag.

Sometimes though if Im on a really tight traffic "Edsa-Like" stop and Go traffic minsan when I step on the brakes to slow down bigla ako may maririnig na very loud vibration. As in VERY LOUD VIBRATION na aakalain mo eh sumayad ka on something.

I just cannot pinpoint that vibration if its coming from the front or the back since its too loud.

Does anyone have a hunch on what problem I might have? Ang hirap kasi pagdating sa talyer, kapag gusto ko na ipakita sa mechanic hindi naman nagmamanifest yung problem.