ebpda9 Posted June 17, 2008 Share Posted June 17, 2008 Well last weekend i wanted to do my brakes and change the rotors, but thru a "stroke" of luck my brake rotors and pads did not fit, so i sent them back. Anyway, i changed the brake lines to stainles steel braided ones, and it all was fine until last night when my pedal actually decided to become soft again. This is only 4 days since me last bleedin the brakes really good. I noticed that my car everytime i bleed it the pedal is normal, but within 3-4 days the brake pedal becomes soft again and the brakes hold like crap. I am at the end of my wits with this problem. I took it to the dealer a few months ago and they noted of my blue ATE brake fluid and gave me the whole lecture how this is not a fluid supported by subaru, blah blah, and they won't touch my brakes. I did not ask them for warranty work either, but the car had the brakes behaved like this since day one, just not this soft. Any work on the brakes will firm up the pedal, but in 3-4 days the pedal becomes soft again. I cannot notice any leaks of brake fluid, and after bleeding the damn car it's fine, but yet no air comes out of it. Any ideas? I thought it could be the master cylinder, or the ABS/EBD unit that's acting up. I am already at my breaking point with this so any sugestions will be more than welcome. Help a brother out. I want to be able to stop for once. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 17, 2008 Share Posted June 17, 2008 i'm gonna go with air in the ABS unit My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
ebpda9 Posted June 18, 2008 Author Share Posted June 18, 2008 why isn't that air coming out when bleeding it. I noticed that when bleeding the level in the pup would go up, then down really quick. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 18, 2008 Share Posted June 18, 2008 you need to cycle the ABS pump.. aka, you need the dealership to do it My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
ilh Posted June 18, 2008 Share Posted June 18, 2008 Can't you cycle the ABS pump by triggering ABS on a hard stop, and then rebleed? It's probably worth a try. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 19, 2008 Share Posted June 19, 2008 ^^ no, cause you need the pump to push the air out the lines while bleeding. If you do it while driving, it's a closed system, the air can't go anywhere. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
CodyItaliano Posted June 19, 2008 Share Posted June 19, 2008 not sure if you can activeate the abs pump while bleeding the brakes but i would maybe try that. i use a vacuum brake bleeder when i bleed the brakes out. works quite effectively and gets a lot of fluid moving through the system a bit more quickly and evenly than most other methods. Harbor freight sells a vacuum brake bleeder that you connect to shop air, or air compressor. thats what ive been using, done many brake jobs without a problem using that. here's a link. it was $29.99 in the store last week when i got a new one. being that its a harbor freight tool, i'd rate this at a 7. not the best, but not quite a piece of crap like some of their stuff is. the price of a much nicer commercial type one is well over $150 if not quite a bit more. http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92924 Link to comment Share on other sites More sharing options...
ebpda9 Posted June 19, 2008 Author Share Posted June 19, 2008 i had a friend of mine looking at the car and he told me that he would not be surprised if my master cylinder would be at fault. I talked to a subaru tech yesteray and he told me that as long as i did not run the abs pump dry i should be fine, and no need for bleeding it. Link to comment Share on other sites More sharing options...
SBT Posted June 19, 2008 Share Posted June 19, 2008 Motive products power bleeder. Works perfectly every time. I have the magnum version which works virtually every vehicle I'll ever run into. http://www.motiveproducts.com/02bleeders.html SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
bsdzine Posted June 19, 2008 Share Posted June 19, 2008 Did you use a 'helper' for bleeding - the good, old-fashioned 2-man system? brian Link to comment Share on other sites More sharing options...
ebpda9 Posted June 20, 2008 Author Share Posted June 20, 2008 it was only done the old fashioned way with the 2 men. I really think the mc is gone Link to comment Share on other sites More sharing options...
SBT Posted June 20, 2008 Share Posted June 20, 2008 This is on your 2005? And you think the master cylinder is gone? Something's not right. SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
ebpda9 Posted June 20, 2008 Author Share Posted June 20, 2008 yup. i really think the mc is gone. What i am going to do tonight is put the car on 4 jackstans remove the wheels and act like driving it, removing one caliper at a time and press on the brake. this should fool the ABS system into opening up and purging the air of the unit. Hopefully my clothing won't catch in the lugnuts. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 20, 2008 Share Posted June 20, 2008 ^^^ that is a really, really, really dumb idea My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
SBT Posted June 20, 2008 Share Posted June 20, 2008 yup. i really think the mc is gone. What i am going to do tonight is put the car on 4 jackstans remove the wheels and act like driving it, removing one caliper at a time and press on the brake. this should fool the ABS system into opening up and purging the air of the unit. Hopefully my clothing won't catch in the lugnuts. BAD IDEA!!!!! - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
bsdzine Posted June 20, 2008 Share Posted June 20, 2008 yea dude, be careful. brian Link to comment Share on other sites More sharing options...
ebpda9 Posted June 21, 2008 Author Share Posted June 21, 2008 all the stupid ideas aside, i did flush the ATE super blue in favor of valvoline sinthetic. The pedal feels a lot better now, but when depressing on the pedal the fluid level goes up in the mc, then down when the pedal is off. Talking to my dad and my friends they all said the mc is gone, and i should buy a new one. Now I just need to figure out a way to get the ate superblue out of the ABS unit. No air came out of the car when i bled it for the billionth time. Link to comment Share on other sites More sharing options...
SBT Posted June 21, 2008 Share Posted June 21, 2008 I'm not so sure I'd be quick to blame the MC. I've never had this issue on one of my Subes, but if the MC was drained dry enough during fluid replacement, you've likely got air in the MC itself and you have to separately bleed the MC - which would give you your fluid surge/subside effect. See the attached Brake System General Description and General Diagnostic Table for more info. Also, follow the attached brake air bleeding instructions, including the part about bleeding the MC. Also, FWIW - The ABS pump itself may be holding pressure against the brake line (think of it as vapor lock if you will) and when you press the pedal you'd see an initial surge in the MC resevoir and then a dip as the pedal pressure subsides. Just a thought and, like I said, I wouldn't be so quick to do a MC replacement until you've exhausted other possibilities. SBT11 - Air Bleeding.pdf01 - General Description.pdf16 - General Diagnostic Table.pdf - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
ebpda9 Posted June 21, 2008 Author Share Posted June 21, 2008 The master cylinder was bled after i flushed out the ate superblue fluid. There was no air coming out of the MC when i finished with it, and the ABS pump had the fuse out. I bled brakes before on abs cars and this crap has never happened. Link to comment Share on other sites More sharing options...
PhilT Posted June 21, 2008 Share Posted June 21, 2008 yup. i really think the mc is gone. What i am going to do tonight is put the car on 4 jackstans remove the wheels and act like driving it, removing one caliper at a time and press on the brake. this should fool the ABS system into opening up and purging the air of the unit. Hopefully my clothing won't catch in the lugnuts. Please video this, just for posterity Double Award Winning Legacy GT Wagon Link to comment Share on other sites More sharing options...
SBT Posted June 21, 2008 Share Posted June 21, 2008 The master cylinder was bled after i flushed out the ate superblue fluid. There was no air coming out of the MC when i finished with it, and the ABS pump had the fuse out. I bled brakes before on abs cars and this crap has never happened. Then the issue, in all likelihood, has got to center around the ABS pump. It sounds like you have been unable to lock brake sufficiently for the ABS to cycle for any length of time, i.e., 60 MPH brake lock and hold until completely stopped. The ABS pump should immediately cycle under these conditions and purge itself. Have you been able to do this? Anyway - good luck with your troubleshooting. I just wouldn't "shoot" the MC too quickly. BTW - what was your rotation for the brakes when you bled them individually? LF, RF, LR, RR is the sequence listed in the tech manual ("Perform the operation in order from the closest wheel cylinder to the master cylinder.") SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
ebpda9 Posted June 21, 2008 Author Share Posted June 21, 2008 Then the issue, in all likelihood, has got to center around the ABS pump. It sounds like you have been unable to lock brake sufficiently for the ABS to cycle for any length of time, i.e., 60 MPH brake lock and hold until completely stopped. The ABS pump should immediately cycle under these conditions and purge itself. Have you been able to do this? Anyway - good luck with your troubleshooting. I just wouldn't "shoot" the MC too quickly. BTW - what was your rotation for the brakes when you bled them individually? LF, RF, LR, RR is the sequence listed in the tech manual ("Perform the operation in order from the closest wheel cylinder to the master cylinder.") SBT hmm, that bleeding proicedure seems totally wrong. The closest wheel to the mc would be the RF according to the piping on the car, because the lines come from the MC to the ABS pump then go from there to each wheel. Also on the vacation pix that i have the procedure is described as LR, RF, FL, RR. The ABS and Brake light should come on when there is air in the ABS pump as per my subaru tech. The ABS pump on my car does come on very easily when the pedal feels like it should. I might get a brake pressure tester and see if the required pressure is at the calipers (About 3500PSI when the ABS pump does not cycle). Link to comment Share on other sites More sharing options...
ebpda9 Posted June 21, 2008 Author Share Posted June 21, 2008 Please video this, just for posterity screw that. I don't want to be a second hogmeat , althou i am thinking about someting to fool the car into thinkinng that it is in motion, and 3 wheels locked and one still spinning. What sucks about it is that the ABS won't work below 6mph. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 21, 2008 Share Posted June 21, 2008 Before you break your car or yourself, take it to a shop and have them do it, where they have the proper tool to cycle the ABS pump. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
ebpda9 Posted June 21, 2008 Author Share Posted June 21, 2008 I took it to the dealer a few months ago and they noted of my blue ATE brake fluid and gave me the whole lecture how this is not a fluid supported by subaru, blah blah, and they won't touch my brakes. that still stands. independent shops will not touch it because of the SSM. so i either fix it on my own or trade it in for something else. Link to comment Share on other sites More sharing options...
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