- Thread starter
- #181
Got the LSPV shipped overnight from Sam Stewart along with all new brake hoses. All replaced this afternoon.
Booster.....
I'm at my absolute wits end- Fading Brake pedal despite best efforts
- Thread starter musthave
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Booster.....
So,I'm following this -peanut gallery style- and the problem is no longer brake 'fade' - i.e. brake function starts out fine, but brake function declines with repeated application of brakes, but soft brake pedal feel?
And still no change?
- Thread starter
- #184
I am reading all of this and understand the frustration. I did the same thing for MONTHS chasing the sponge demon. Spent way too much time on it only to find out it was the brake booster push rod. I don't have the sports car level of feel but I am more than happy with them.
Here I don't see that it has been checked but, for something so easy to do, I would rule that out before removing any safety equipment or spending any more money. Worst case scenario, you over tighten it and have to back it off a few turns. Just sayin
If the pedal isn't hard as a rock, explain how it could be the booster, I just don't see it.
We took vacuum off booster, had hard manual pedal but it faded to no brakes just the same.
- Thread starter
- #185
We won't know until tomorrow. Darkness comes early this time of year.
- Thread starter
- #186
Correct. Someone corrected me early on, it's not truly brake fade. Pedal fade. Or soft brake pedal.
Last edited:
- Thread starter
- #187
We might just do that.
Me, no mechanic, but inclined, and after seeing what a dealer did on my cruiser with PO, little chance it will see another. No offense to the reputable ones
Where are you located?
"Spongy brakes feel like you have a sponge on the pedal". Pin_Head
"and under the sponge is a bag of marshmallows, but the truck doesn't stop". I won't even test drive it.
This is the current condition, and condition at the beginning. feels like the master is wonked
"and under the sponge is a bag of marshmallows, but the truck doesn't stop". I won't even test drive it.
This is the current condition, and condition at the beginning. feels like the master is wonked
I have heard that it is possible compressing the pistons in a really bad and dirty system can sometimes be enough to push gunk up through the system and into the master effecting the seals. Usually it is old masters that have issues, but could effect a new master as well. When you pushed your pistons back in did you crack your bleeder? Maybe see if you can get Beno to have Toyota warranty the master?
We might just do that.
Me, no mechanic, but inclined, and after seeing what a dealer did on my cruiser with PO, little chance it will see another. No offense to the reputable ones
Where are you located?
We're over in Tampa. Not sure what we can do aside from pass you tools, put bolts in/take them out, or hold extensions, etc, but it's sometimes nice to have an extra pair of hands to hold a socket or something. PM us and we'll set something up.
That would be user error/system error and not mechanical failure due to manufacturer fault which is the only time I warranty parts.
Problem is that no one seems to be diagnosis anything and parts are being thrown at it. *Anything* in this system could be wrong at this point.
Last edited:
Sorry
From the horses mouth:
See the first section about "spongy brakes."
Notice that everything has been done done on this list in the first box to the right except for the last bit about the booster. Has the booster been checked? Has the rod adjustment been checked?
Has the master been tested to see if it is indeed faulty per the FSM? This is troubleshooting document that should be referring to.
See the first section about "spongy brakes."
Notice that everything has been done done on this list in the first box to the right except for the last bit about the booster. Has the booster been checked? Has the rod adjustment been checked?
Has the master been tested to see if it is indeed faulty per the FSM? This is troubleshooting document that should be referring to.
Fluid was clear throughout the system with the exception of the right front had some stain and crumbly particulate initially, and also at the right front after cycling ABS, first time only, subsequent stayed clear.
Replacement calipers were both wetted before the pistons were moved for the first time.
Master was wet (both replacement MC's) before pushing the plunger through the first time.
From Toyota:
Booster Push
Rod Gauge
Booster Push Rod Adjustment
Check this adjustment any time the master cylinder or booster is replaced. It ensures the correct gap between the master cylinder piston and booster pushrod. If not correctly adjusted:
• If the gap is too small, the brakes may drag and, with enough heat buildup,
the brakes may lock. Dragging also results in premature brake wear.
• If the gap is too large, there will be reduced pedal reserve distance and a
slight delay in brake application.
Before adjustment, check the brake pedal free play to make sure the booster is
not partially applied.
Use Special Service Tool (SST) Brake booster push rod gauge (SST
#09737-00013-01):
• Set SST on master cylinder with a new gasket.
• Lower pin until tip slightly touches the piston.
• Turn the SST over and set it on booster (must have vacuum charge – start
engine).
• Adjust booster push rod length for zero clearance (refer to repair manual for
details).
Booster Push
Rod Gauge
Booster Push Rod Adjustment
Check this adjustment any time the master cylinder or booster is replaced. It ensures the correct gap between the master cylinder piston and booster pushrod. If not correctly adjusted:
• If the gap is too small, the brakes may drag and, with enough heat buildup,
the brakes may lock. Dragging also results in premature brake wear.
• If the gap is too large, there will be reduced pedal reserve distance and a
slight delay in brake application.
Before adjustment, check the brake pedal free play to make sure the booster is
not partially applied.
Use Special Service Tool (SST) Brake booster push rod gauge (SST
#09737-00013-01):
• Set SST on master cylinder with a new gasket.
• Lower pin until tip slightly touches the piston.
• Turn the SST over and set it on booster (must have vacuum charge – start
engine).
• Adjust booster push rod length for zero clearance (refer to repair manual for
details).
Poor Mrs Darness
I always clamp off pipes when fault finding but, I do not use vice grips as it is easy to 'over do it' with the power the things can bring to bear. I use a proper brake pipe clamp tool, it is designed to close off pipes without damage to the inner tube or outer sheath.
regards
Dave
regards
Dave