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brake issues

4281 Views 34 Replies 11 Participants Last post by  Bladester
i just finished a complete brake overhaul. new akebono pads front and rear, rotors turned, new stainless lines front and rear and complete fluid flush. now for the bad news. after bleeding the lines for over an hour i cant get the pedal to stiffen. the bas /esp lite comes on then switch the key off and on it goes out. if the pedal is pumped the pedal increases stiffness. but release the pedal and apply again it goes rite to the floor! i tried pumping the pedal over 70 times to open the abs ports to no avail. i have bled over a pint of very expensive brake fluid and still no pedal.
anyone have any ideas as to what im doing wrong? i have done brakes on many american cars and swedish cars with no issue. i have never encountered so soft a pedal.
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You probably know more about this than I do, been a long time since I've done a brake job. My recollection is that you start with the bleed screw furthest from the master cylinder and work your way closer. For me, it was always a two person job: one to pump the pedal, one to bleed the air out and close off the bleed screw when done. Please forgive if you already know all this stuff, sounds like you already have done this many times.

yep larry you got it! i started at pass. rear then driver rear pass. front then driver front with my buddy pumping the brake pedal. we counted over 150 pumps of the pedal with no increase in pedal pressure. first push it goes to the floor bas/esp lite comes on. shut car off light goes out. im at a loss
My old Porsche 928 has a bleeder on the master cylinder too.
i dont see any bleeder on the m/c. any ideas?
this just keeps getting better! i drained the coolant ran distilled water for 20 min and drained it. refilled with 1.5 gal of m/b antifreeze and 1 .25 gal of water. now i dont have any heat!!!!! this sh*& was supposed to be easy! im getting really frustrated!
Hey Krazi,

You have air in the lines. Pumping the pedal does not effectively bleed the bake system. Although I have been lucky once or twice.

Bleed the brakes with a power bleeder. A power bleeder is a vessel that is filled with brake fluid and then pressurized with air from your spare tire. The fresh brake fluid is forced into the reservoir to the calipers. Open one caliper at a time and allow the fluid to run until clear. Don’t let the reservoir run dry.

The ABS/BAS may pop on if the brake pedal travel is excessive. Next time braking the system should reset and no light.

were do i find this power bleeder? is it connected to the resevoir or at the bleeders? the light resets but i am unable to keep a pedal
can this be done with the car up on jackstands? its almost impossible to reach the rear brakes with the wide rims (8.5 wide)
I always used a clear hose (tubing) going from the bleeder valve into a glass half full of brake fluid. Loosen bleed valve. As pedal pumped by your long suffering assistant, you watch for air bubbles in the liquid. When no more air bubbles, hold the pedal down and tighten the bleeder valve. Remove tubing. Yes, did it with wheels off the car (and no, I haven't done it on my SLK).

did all that larry. i have bled tons of brakes in my time but this baffles me. so im ordering motives power bleeder zill recommended and see if i pressurize the m./c i can push what air is in the lines out.
since i had the calipers off the car and the rubber lines replaced with stainless lines there must be air trapped in the calipers.
Sounds like you've tried everything many times. This may be an issue with the new lines or a small leak in the connections causing the bubbles to come back. I would just put on the old lines and see it they stiffen. It's worth a try since nothing else is working. From my experience I never needed any special tools, just stick to the old fashioned 2 person bleed technique, but reverse troubleshoot by using the old lines...

Might as well switch back to the inexpensive brake fluid till it's figured out. Have you tried letting the engine idle while bleeding?
im thinking with the calipers completely compressed new lines and a flush i must still have air in the lines. unfortunately to remove the stainless lines i have to pull the wheels remove all the calipers and then the lines! before i do all that ill try a pressurized system first
it will prolly take about a week or so to get my power bleeder. ill post my results. any ideas as to why i have lost my heat? coolant flush went fairly smooth. watched temp come up to operating range then no heat!
it will prolly take about a week or so to get my power bleeder. ill post my results. any ideas as to why i have lost my heat? coolant flush went fairly smooth. watched temp come up to operating range then no heat!
bad karma?

Check your coolant level again. How much coolant did you add? May look full but entrapped air could fool you.


As to the brakes, you have air trapped somewhere, you already know that. Once you get the power bleeder tied into the MC the air will be blown out, and you'll see where it was.
There are times when air is trapped in the master cylinder itself, it's hard to get out using 'standard' practice. The power bleeder will help you out, but be sure you have plenty of fluid in the bleeder.

The coolent system also has air trapped in it. be sure you have the system on full heat, leave the cap off of the overflow tank and add 50/50 mix as you run the engine. It may take time, but the air will 'burp' out.
thanx bruce. if i leave the cap off i have a diffucult time reaching 80 to 100 on the gage. with the cap in place i can reach operating temp. so far i have 1.5 gal of antifreeze and 1.25 gal of distilled water. i had heat when running pure water to flush. shut car off and drained hot. then refilled with mix and voila! no heat! ill start again sun

open road im sure karma is kickin my butt! when i left to recycle some old oil so i could drain the slk oil my trusty truck wont start!!! :shit not::bash: so in the span of about 4 hrs i went from 3 running cars to 1!

heres a bright update. oil change went without a hitch. drained from the bottom and let it sit overnite. refilled with mobil 1 and while warming up the motor the heat returns! coolant flush finished need 14 mm hex for the rear diff. and power bleeder. wish me luck!
karma is getting better. found the hex socket for the rear diff. in aset for under 15$. seems like the truck needs a starter so off to the parts store!
hope your karma continues to turn for the better...
karma is even again! truck now starts, m/b only needs brake bleed and tranny flush and i only bled at the knuckles briefly!!
Were you having low brake pedal problems before you started this job?

I've bled the brakes on my wife's SLK 230 and it did take a lot of pumps relative to other cars that I've done. When finished, the pedal seemed soft compared to my Honda, but it stopped on a dime.

I've had a similar scenario to your low or no brake pedal after doing a brake job. This was on a an Acura Integra and I could never get any pedal, just a slow resistance down to the floor. It ended up being a bad master cylinder and that sounds like the one remaining thing you have not replaced. How many miles on this car?
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