PDA

View Full Version : Mushy Brake Pedal


87MCProstar
10-24-2011, 04:53 PM
Hey guys,

Since there a lot of car nuts on this site as while I thought I'd hit as many places as possible.

I just get a brake job on my Mountaineer (front calipers, rotors/pads), bleed all 4 calipers and MC 3 times, but still have a mushy pedal.

Anyone have any ideas??

joniron1
10-24-2011, 05:09 PM
maybe a bad brake line . On motorcycles the rubber flexible line can go bad with no visible damage and give a mushy lever no amount of bleeding will eliminate.

trickskier
10-24-2011, 05:12 PM
Was it mushy before?

Ron Grover
10-24-2011, 05:16 PM
Proper brake fluid?

Thrall
10-24-2011, 08:52 PM
Master cylinder bleeding by internally?
How many miles, how old?
Why would the master cyl need to be bled at all?
That should be a clue, no need to bleed the mc for new brake pads, however, I've had master cyl's take a crap after doing a brake job (on high mile cars) and pushing all that fluid back through them.

03geetee
10-24-2011, 09:07 PM
As a ford nut I can tell you its one of two things....

-ABS controller got air in it and needs to be bled at the dealer, if you ever let the master go dry while bleeding this can happen.

-leak or soft line about to fail that is very soft and spongey.

Hope this helps bro!

JTR

j.mccreight@hotmail.com
10-24-2011, 11:36 PM
Why were the calipers replaced? I've replaced maybe 10 calipers that were bad in the 16 years ive worked on cars at a dealership...thats how just brakes, brake check etc. make their money, you go in for their 99 dollar brake job then they give you some bs saying rotors, calipers etc need to be replaced, 99 dollar brake job turns into 600, when all you needed was some pads and rotors resurfaced, not saying this happened to you per say, but I see it all the time, so and so just did my brakes and now they don't work right and they replaced everything...

87MCProstar
10-25-2011, 09:08 AM
I think 03 has hit it on the head. While flushing the system after brake job, I must of dryed out MC putting air into ABS system. Get to bring truck to good ol' Ford dealership. Just hope they don't rake me over coils.

87MCProstar
10-25-2011, 09:10 AM
J, had to replace front left caliper due to one frozen piston. When using the C-clamp to reset caliper one of the pistons would move back to starting position.

j.mccreight@hotmail.com
10-25-2011, 10:27 AM
I think 03 has hit it on the head. While flushing the system after brake job, I must of dryed out MC putting air into ABS system. Get to bring truck to good ol' Ford dealership. Just hope they don't rake me over coils.

If that is the case then yes you have to take it to ford dealership as they have a "special tool" that opens the actuator so proper bleeding can occur.

ahhudgins
10-25-2011, 07:24 PM
If that is the case then yes you have to take it to ford dealership as they have a "special tool" that opens the actuator so proper bleeding can occur.

Does it have to go to Ford or can most garages do it as well? The pedal on my F150 is always a little soft and gets worse during the winter. I'm going to replace the rotors and pads myself and then I wanted to get the MC replaced and have the whole system bled.
I hate going to the dealership because it never costs less than $600!!!!

j.mccreight@hotmail.com
10-25-2011, 08:23 PM
Does it have to go to Ford or can most garages do it as well? The pedal on my F150 is always a little soft and gets worse during the winter. I'm going to replace the rotors and pads myself and then I wanted to get the MC replaced and have the whole system bled.
I hate going to the dealership because it never costs less than $600!!!!

Its fords scan tool and a jumper harness that operates the system for a complete bleed. On your truck you can bleed your brakes, just don't let the master cylinder go dry while pumping. You should be able to replace your mc without messing with the abs. Bench bleed the mc install and then bleed the calipers.

ahhudgins
10-25-2011, 09:01 PM
My Haynes manual said that if I open a line before the ABS that I must take it to a dealership so they can put it on "their computer" (it's a 1997). I know a local mechanic that I trust and I'm going to ask him if he has the right test set up to do it. The pedal has always been spongy since I bought it used and the pedal will slowly bleed down at stop lights when the temps get down below 40 or so. Winter is coming!! :mad:

87MCProstar
10-26-2011, 08:19 AM
On your truck you can bleed your brakes, just don't let the master cylinder go dry while pumping.

I just found out that you don't want to MC to drop below 1/4 full. You increase chances of getting air into the system.

03geetee
10-26-2011, 07:10 PM
I just found out that you don't want to MC to drop below 1/4 full. You increase chances of getting air into the system.

Did you get her fixed?

Was I right? I want a cookie.

LOL!

JTR

Kyle
10-26-2011, 07:11 PM
If that is the case then yes you have to take it to ford dealership as they have a "special tool" that opens the actuator so proper bleeding can occur.

Is the "special tool" a line wrench??? Or is there really a specialty tool for this job???

jakethebt
10-26-2011, 07:14 PM
It is sounds like air in the abs valve block. The techs need a computer to cycle the ABS motor so the valves can open and close and get any trapped air out. This air then goes up to the mater as air likes to travel to the top of the fluid. You usually then need to re-bleed the master.

Is you dont want to pay the big bucks, some times smaller shops have a hand held code readers that will also cycle the ABS.

If you want, you can try the Bill Hilly way for free... find a nice open parking lot just after it has rained. Look for one with the sealer that is put on with a mop or spray. These are the kind that are super slick when wet. We have several churches around here that are like that and there are almost no cars/traffic except on Sundays. Do some fairly low speed, like 20mph abs stops in the parking lot with no one around. You are looking for the ABS to kick in for several seconds. You might need to adjust the speed and be agressive on the pedal to get the abs motor to cycle. Do about 3 or 4 of these and you will get the air out of the valve block. Now you may have moved the air into the master cylinders. Do some light brake applies where you have moderate pressure on the brake pedal. If you have small amounts of air in the master, you can often times get it to self bleed back into the reservoir. This sounds stupid, but it has worked for me in the past and could save you some bucks. And it costs you nothing to try...

ahhudgins
10-29-2011, 10:56 AM
I talked with a mechanic that I've known for over 20 years (and I trust) and he said that you will never get the air out of an ABS system without the proper computer system (tool). I will ask him when I take my 97 F150 to him next week, but he also asked me what year my truck was so I'm guessing the year and model makes a difference in the tool?

I'm putting rotors and pads on the truck today and I'm letting the garage do the master cylinder and then bleed all of the lines. On a side note: This time I bought my rotors and pads from Ford instead of Autozone. The rotors come in the exact same plain white box and are made in China. The pads come in a Ford Motorcraft box and are made in Thailand, and everything cost me twice as much as Autozone for the same foreign junk. :mad: