Had my brakes flushed, Brakes feel a little spongy, If i am at a stop light and press on the pedal it goes down quite a bit but not to the floor ,Do you think there could be air in the line or a bad master cylinder , Car is a 91 with 31000 miles
Spongy brake pedal
- Thread starter danny49
- Start date
Those would be the two main culprits.
Bram
Bram
When the brakes were flushed, did they use a pressure bleeder or did they do the pump the brake pedal to build pressure for flushing and bleeding? If they did the latter, chances are they pushed the pedal past its normal travel range. Over years of use a ridge develops in the MC cylinder walls at the end of the normal travel range. If you push the pedal past that normal range the seals on the piston hit that ridge and are typically damaged which results in leakage of the fluid past the seals and back up into the reservoir (and the pedal heading towards the floor).
You can try bleeding your brakes again to see if there is air in the system. If no air comes out I think you are into replacing the master cylinder. If they bled the brakes using the pedal pump method then I would put a very high probability on the MC being damaged and you might just want to jump right to replacement. Been there, done that (not on the NSX). Now I always use a pressure bleeder or a vacuum if I don't have a proper adapter for the MC for use with the pressure bleeder.
You can try bleeding your brakes again to see if there is air in the system. If no air comes out I think you are into replacing the master cylinder. If they bled the brakes using the pedal pump method then I would put a very high probability on the MC being damaged and you might just want to jump right to replacement. Been there, done that (not on the NSX). Now I always use a pressure bleeder or a vacuum if I don't have a proper adapter for the MC for use with the pressure bleeder.
Brakes
Just had the “upgrade” ABS system installed along with a ton of other work done and updates as well and just don’t dick around and replace the master cylinder. It’s not very expensive and it should, as Old Man said do the trick. If you still have the original ABS system save a few bucks up and do the update. It’s the smart way to carry on.
Cheers
nigel
Just had the “upgrade” ABS system installed along with a ton of other work done and updates as well and just don’t dick around and replace the master cylinder. It’s not very expensive and it should, as Old Man said do the trick. If you still have the original ABS system save a few bucks up and do the update. It’s the smart way to carry on.
Cheers
nigel
The car is almost 30 years old. I’d bet the master cylinder and many other seals and hoses are going to fail. Replace the MC.
Thanks guys for the information, I will look into it
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Thanks guys for the information, I will look into it
I find the brake master to be expensive. Amayama does have rebuild kits for the master to keep costs down a bit.
https://www.amayama.com/en/catalogs/honda/nsx/1-coupe-right-1990-1/7/1629
https://www.amayama.com/en/catalogs/honda/nsx/1-coupe-right-1990-1/7/1629
I'm in similar situation to you. Just bought 91 with 43k miles. Had he timing belt and pump changed and decided to change brake fluid out same time. Over weekend I drove and the brakes went all the way to the floor. After further research I came to same conclusion everyone else is mentioning. Its the master cylinder. They pumped the brakes for the change and may have caused internal seals to fail. New master cylinder not that bad being around $350, OEM Nissin. Problem is that they are on a back order throughout the US and can only be gotten from Japan.
Has anyone replaced MC with Centric brand? if so how is your experience with aftermarket brand?
Has anyone replaced MC with Centric brand? if so how is your experience with aftermarket brand?
I used the Centric on my 91. It started leaking after about 3 years and had to be replaced with OEM by the new owner.
I doubt they pushed too hard on the brake pedal. The MC is 29 years old. The fluid in there was probably a few years old also. When they put in new fluid, it probably had a lower viscosity making it possible for the fluid to seep past the seal on the piston in the MC. While you are at it, it's probably a good idea to replace the master and slave for the clutch.
That makes sense also. Thank you for suggestion on master/slave for clutch. I have asked dealer to look into those parts as well. I knew what I was getting into when buying a car this old. Thankfully parts and labor are not ridiculous on this car. Its just seems to be harder to get the OEM parts as the car ages.
Centric can be OEM or lessor quality; probably depends on which supplier they buy from. The Centric clutch slave was OEM.
My best supplier for Nissin was http://sandlbrake.com/
My best supplier for Nissin was http://sandlbrake.com/
Similar situation to my 92, pick up the car in Feb, feel the brake pedal is very soft and first I thought maybe there's no pad left thus change all 4 rotors and pads and have the mechanic bleed the brake fluid.
same soft pedal feel after driving for couple day thus thought maybe the Hawks pads are soft type or bubble in the brake line (which is rare cos the mechanic is well experienced)
Anyway, bleed the brake line again and squeezed out some bubble.
No luck still the same after couple days and it's getting worse, pretty sure it's the BMC.
Yes, very hard to find good replacement unless going for the expansive Nissin..
And being in Canada make searching parts even more difficult..
Eventually got one from the brand called WBR, I read many posts from this forum and don't have a good feeling on Centric thus look for some other brand.
Have the WBR one put on since Aug, so far so good, price is not bad, around $200, 2 years or 24000 miles warranty...
same soft pedal feel after driving for couple day thus thought maybe the Hawks pads are soft type or bubble in the brake line (which is rare cos the mechanic is well experienced)
Anyway, bleed the brake line again and squeezed out some bubble.
No luck still the same after couple days and it's getting worse, pretty sure it's the BMC.
Yes, very hard to find good replacement unless going for the expansive Nissin..
And being in Canada make searching parts even more difficult..
Eventually got one from the brand called WBR, I read many posts from this forum and don't have a good feeling on Centric thus look for some other brand.
Have the WBR one put on since Aug, so far so good, price is not bad, around $200, 2 years or 24000 miles warranty...
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