Need help in braking problem

[aliking]

Today I was stopping on a traffic light and when the light turned green and i went forward, i wanted to push on the brake a little afterwards but i felt that the brake pedal became somehow loose and didnt brake at all, however 10 seconds later, the brake pedal restored and became normal again, This was really dangerous and i thank God that the brake pedal restored and i could stop, All the braking system in my car in good condition, new brake pads, new disc brakes, new hoses, oil fluid level is ok and never had any problems.
I need some suggestions in what to check to prevent this from happening again.
Thanks.

 

[sheward]

When was the last time the fluid was replaced, and the system bled? Seems like you may have a master cylinder problem although it could possibly just be air or water in the system.

I suppose the ABS block or pump could also be suspect. Comments suggest it's a bit difficult to bleed the system correctly.

Should it happen again before you get it sorted be ready with your parking brake as insurance if you can't let it sit.

 

[gsxr]

I don't understand the symptoms. Was the pedal too firm (required too much effort), too soft (went towards the floor with no braking action), or something else entirely?

 

[aliking]

When was the last time the fluid was replaced, and the system bled? Seems like you may have a master cylinder problem although it could possibly just be air or water in the system.

I suppose the ABS block or pump could also be suspect. Comments suggest it's a bit difficult to bleed the system correctly.

Should it happen again before you get it sorted be ready with your parking brake as insurance if you can't let it sit.

I never changed the brake fluid, i bought the car at 2018, and never changed the fluid. Thank you for the comment i will keep the parking brake ready till i figure out the reason.

 

[aliking]

I don't understand the symptoms. Was the pedal too firm (required too much effort), too soft (went towards the floor with no braking action), or something else entirely?

Yes thats what happened exaxtly:
too soft (went towards the floor with no braking action).
Im sorry but my english is not that good to explain it exactly but thank you for the explain.

 

[sheward]

Whoever did the brake work, including hoses, would have had to bleed the system. It's possible they did not get things right although I would think any problem would have appeared before now. Fluid change is due about now so I would start there and make sure it is done per factory specs.

Dave or others may have more insight.

 

[aliking]

Whoever did the brake work, including hoses, would have had to bleed the system. It's possible they did not get things right although I would think any problem would have appeared before now. Fluid change is due about now so I would start there and make sure it is done per factory specs.

Dave or others may have more insight.

Thank you again, correct, im sure they didnt fully bleed the system, what i see in the brake fluid reaervoir is yellow oil which i think is DOT 4, i think i will replace tbe fluid and use DOT 3. And for sure i will search for the thread about the brake fluid bleeding, and to follow the bleeding instructions carefully.

 

[gsxr]

Make sure to use at least DOT4, and preferably DOT4+ fluid! These have a higher boil point. I think there's some old threads with more info on fluids. I don't know what aftermarket brands are available in Jordan, but the OE Genuine MB fluid is excellent if available. To flush the system with a pressure bleeder, only 1 liter is required.

 

[aliking]

Make sure to use at least DOT4, and preferably DOT4+ fluid! These have a higher boil point. I think there's some old threads with more info on fluids. I don't know what aftermarket brands are available in Jordan, but the OE Genuine MB fluid is excellent if available. To flush the system with a pressure bleeder, only 1 liter is required.

Ok i will use DOT4+
We have lot of aftermarket brands like Ate & Texter, but the geniune mb fluid is also available here, thank you so much

 

[gsxr]

Ate Type 200 or SuperBlue are also excellent - highly recommended, if easier to obtain vs OE MB fluid.

 

[aliking]

Ate Type 200 or SuperBlue are also excellent - highly recommended, if easier to obtain vs OE MB fluid.

Luckily both are available

 

[nocfn]

new fluid pressure by feed should replace the system to its normal. Be sure to pressure bleed the ABS as well.

 

[aliking]

new fluid pressure by feed should replace the system to its normal. Be sure to pressure bleed the ABS as well.

I will make sure to completely bleed the system including the Abs/Asr pump.
Thank you so much

 

[King13ls]

I’m currently about to fix my asr rear brake line, and I’m wondering will I have to pressure bleed it or not sence it’s doesn’t have any brake fluid

 

[gsxr]

I’m currently about to fix my asr rear brake line, and I’m wondering will I have to pressure bleed it or not sence it’s doesn’t have any brake fluid

How does a rear brake line not have any brake fluid? All the brake lines (steel tubing and rubber hoses) should have fluid.

 

[King13ls]

well one day it muddy and I had to move my car out the way and Pressing on the gas I guess the asr came on and the rear brake line busted, but I just now finished making the brake line for it,

 

[King13ls]

well one day it muddy and I had to move my car out the way and Pressing on the gas I guess the asr came on and the rear brake line busted, but I just now finished making the brake line for it

Actually no that I put brake fluid in I’ve realize that’s both of the rear brake lines are busted

 

[aliking]

Im sorry i forgot to update this thread,
Problem solved after changing the fluid and full bleed for the system, great performance now.
Thank you all for the helpful informations

 

[King13ls]

Okay both rear brake lines repair I must say that the right one was a BIG pain to get in, but the brakes feels like there holding pressure now

 

[King13ls]

Update: both rear brakes have been renewed and I took the car out for a spin last night and I must sayyy the car is running like a beast and it’s definitely feels like it’s riding a lot more smother, but this morning waking up I noticed that my car was leaking brake fluid and I briefly check and the bolt of the compression fitting had cracked witch was crazy to me there was no sign that it got dragged or anything, but I’m guessing that’s it just cracked from how cold it was last night witch doesnt make much sence to me but yeah

 

[Alphasud40]

Im glad you discovered before driving it and discovering it! New banjo bolt and crush washers and I would consider doing the other side as well. Find the torque spec and use that during installation. Hollow bolts can stretch easily.

 

[JC220]

Sorry but I'm not following the logic in the 2no above posts:


Compression fitting cracked?
New banjo bolt and crush washer
Hollow bolts stretching?


No w124 brake system has banjo bolts as standard. There should also be no compression fittings on a brake line.

When you say the rear brake lines were burst what do you mean exactly? Rusted se teel lines or thrubber flex hoses? How was it fixed?

I can only presume you mean the rubber hoses and the flared steel brake line fitting/ connection is leaking. Possibly due to overtightening. There is no torque setting that I am aware of just by feel and to always avoid overtightening. Never once heard of these brake pipe nuts stretching that would be something else!!

For your safety and other road users if in any doubt about what you are doing on the brake system take the car to a competent shop / mechanic.

 

[Alphasud40]

Apologies to the mislead. based on what he was describing it sounded like he was dealing with a a banjo style compression fitting like what you find on a lot of brake calipers. Absolutely if it’s a flare fitting that requires a line wrench to tighten it’s by feel. sorry for the confusion.

 

[King13ls]

No the rubber hose appears fines, the actual line was rusted and I assume when the asr came on the pressure caused it to burst so I had to replace the whole brake line from the wheels, to where the all the lines meet by the hole cap for the the jack, and as for where the brake lines goes to the rubber hose i Flared it right,

 

[King13ls]

That bolt is what cracked witch was super odd to me, but I replaced it and bleed my brakes and everything and the brakes are good,