HeuiTim Posted August 21, 2008 Share Posted August 21, 2008 I have to replace the two braided lines from the master cylinder to the abs module, the factory service manual references itself in the abs/non abs bleeding procedures. So do I just bleed them normally, are there bleeders on the module? Who at Ford would think that crimping a stainless steel flex line to a steel line would ever be a good idea, they do get snow in michigan right? Quote Link to comment Share on other sites More sharing options...
Tony302600 Posted August 21, 2008 Share Posted August 21, 2008 crack the lines at the abs module and let it gravity bleed. Unless you do a HCU unit i dont think you would HAVE to ABS bleed em. /forums/images/%%GRAEMLIN_URL%%/2cents.gif Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted August 21, 2008 Share Posted August 21, 2008 When I have Super Duty cabs off I will simply take a pry bar and collapse the calipers forcing fluid and the air back up into the master cylinder. Remember to pump the brakes up before you do anything else. Works very well and no bleeding. /forums/images/%%GRAEMLIN_URL%%/grin.gif Don't know what vehicle this is but it needs to be disk brakes all around to work. Quote Link to comment Share on other sites More sharing options...
jared_bortel Posted August 21, 2008 Share Posted August 21, 2008 Keith, I have to ask, how are disassembling a Super Duty cab that requires brake bleeding? Can't you just lay the HCU and master cylinder over on the motor? Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted August 21, 2008 Share Posted August 21, 2008 Depends on the model year but I prefer to just remove the lines from the top of the HCU. TO ME it is simpler and neater. You know, you say tomaaayyyto, I say tomaaahhhto. /forums/images/%%GRAEMLIN_URL%%/laugh.gif Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted August 22, 2008 Share Posted August 22, 2008 Tim... if you feel there is a chance that air got into the accumulator on the HCU, you can perform a "service bleed procedure" using a capable scan tool.... You bleed the brakes normally and then use the scan tool to cycle the pump and valves - then you bleed the system normally again.... In the shop, we wouldn't normally have air entering the HCU even if we allow the system to completely dry..... However, ours is not a perfect world and shit happens on an all too regular basis. My own preference is to do my best to make sure the customer never has the opportunity to say "ever since you <whatever>, my <thingie> is screwed up"... (Some newer models have vehicle dynamic systems that wont let you bleed brakes without a capable scan tool). If you decide against performing a service bleed where one "may" be a wise choice (it's only a few extra minutes to assure your customer get's better treatment than PepBoys) - at least finbd a stretch of gravel or such and perform a couple of "ABS assisted" stops. Actuating the pump and valves should send any air trapped in the accumulator into the hydraulic system and should reveal itself as a change in pedal feel. Important consideration.... If you have had the brake system open, there is a very real chance that you aren't the first person.... What YOU do may not allow air into the wrong places... but what someone else has done might.... And if you are the last guy to bleed the brakes........ FWIW, I currently have an 06 F550 on my hoist..... There is a town about 2 hours away from hours.... In this town, there is a man.... On the breast of his coveralls we see two patches. Over one tit, he displays the name "Butcher Moters"... over the other, his name "Ben Dover". This shop charges an extra 20% if you don't supply you own vaseline or ask for a kiss.... (the kiss? most of us like a little lovin' with our fuckin'). But this would be a truck that could have had ANYTHING happen to it in the shop.... The short answer... I regularly perform service bleeds. It is VERY RARE to find air in the HCU. From the customers standpoint - it only takes once for a laundry schedule change to happen. If the job is retail, word the estimate "perfrom electronic service bleed procedure". For warranty purposes, follow the WSM AFTER checking OASIS. You never get a second chance to make a first impression. Quote Link to comment Share on other sites More sharing options...
BrunoWilimek Posted August 26, 2008 Share Posted August 26, 2008 Depends on the model year but I prefer to just remove the lines from the top of the HCU. TO ME it is simpler and neater. You know, you say tomaaayyyto, I say tomaaahhhto. /forums/images/%%GRAEMLIN_URL%%/laugh.gifThe tech next to me does it this way as well. I prefer to leave the lines connected and wire the master and HCU on the engine, making sure they are not going to be crushed when lowering the cab. The newer ones have only one 10mm head bolt to be removed to take the HCU out of the bracket and 2 nuts on the master, as well as the 3 electrical connectors. The reason I do it this way is that brake fluid absorbs water, and I prefer not to let it do this as I don't know how long it will have to sit before re-assembly. For instance, the last one required a short block, AWA inspector to come and verify it, and I took a week off for a vacation between the time I took it apart and re-assembled it, so it sat on my hoist for the better part of 2 weeks. How long would I have had to bleed that one to get rid of the water in the brake fluid? Getting back to the original question, I just replaced one of those lines on an 02(HCU to left front flex hose)and I simply bled it manually. I have used the "braking on gravel" trick in the past to make sure no air was left in the system, but didn't feel it was necessary in this case. Quote Link to comment Share on other sites More sharing options...
Mekanik Posted August 29, 2008 Share Posted August 29, 2008 If you decide against performing a service bleed where one "may" be a wise choice (it's only a few extra minutes to assure your customer get's better treatment than PepBoys) - at least finbd a stretch of gravel or such and perform a couple of "ABS assisted" stops. Actuating the pump and valves should send any air trapped in the accumulator into the hydraulic system and should reveal itself as a change in pedal feel. This is actually very important, and I try to do it after doing any hydraulic ABS repair. If there was air in the HCU, the next time the customer makes a ABS stop, the pedal will go right to the floor and the vehicle won't stop. A Ford instructor was telling us about this and mentioned that on one particular vehicle ( I think it was a contour) there was no ABS bleed procedure and suggested what Jim mentioned. The actual function of the ABS motor is to re-supply the hydraulic system with brake fluid so it can make another stop. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted August 29, 2008 Share Posted August 29, 2008 James.... we are at the point where find myself referring to the shop manual at a rate that could almost be regarded as alarming... The changes and caveates to some of the simplest procedures are starting to show.... engineer playing CYA or stuff that will return to bite? From the 2008 Fusion WSM "NOTE: Due to the complexity of the fluid path within the rear integral parking brake calipers, it is necessary to press and release the parking brake during the bleed procedure". Here is step 4 from the manual bleed procedure for an 08 Taurus X.... "Loosen the RH rear bleeder screw until a stream of brake fluid comes out. While the assistant maintains pressure on the brake pedal, tighten the RH rear bleeder screw. Press and release the parking brake 5 times. Repeat until clear, bubble-free fluid comes out. Refill the brake master cylinder reservoir as necessary." How many techs read the WSM for something as butt simple as a brake bleed? (Before we spend umpteen hours replacing damned near every part in the system - simply because traditional methods are becoming obsolete?). Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted August 29, 2008 Share Posted August 29, 2008 The changes and caveats to some of the simplest procedures are starting to show.... engineer playing CYA or stuff that will return to bite? Jim, your wisdom and observations are awesome. While some of us are preaching to our young techs to RTFM we all need to get back into that habit for the very reason Jim has pointed out. Originally Posted By: Bruno Wilimek The reason I do it this way is that brake fluid absorbs water, and I prefer not to let it do this as I don't know how long it will have to sit before re-assembly. Good point. /forums/images/%%GRAEMLIN_URL%%/thumbup.gif Quote Link to comment Share on other sites More sharing options...
BrunoWilimek Posted September 4, 2008 Share Posted September 4, 2008 The aforementioned tech just did a set of headgaskets on an 06 F250 6.0. The gaskets took several days to arrive' date=' including a 3 day weekend in there as well. He just had another tech pump the brakes and he bled the lines where he disconnected them. Brake fluid ran all down the LF tire while the lines were disconnected. How much water was absorbed by the fluid? I Dunno? Is this the proper way to do the job? You decide. [img']/forums/images/%%GRAEMLIN_URL%%/2cents.gif[/img] Quote Link to comment Share on other sites More sharing options...
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