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KEN C: "The trick to doing a perfect bleeding ... is to NOT touch the brake pedal. I use a pressure bleeder instead of pressing on the brake pedal."
MY REPLY: I understand the reason why, because if you press on the pedal you are shutting off the pressure of the pressure bleeder. No, that is not what I did. I only had the pedal pushed down enough to hook up the vehicle lines and to prevent any air from going into the MC (or at least as little as possible), i.e., "the inevitable step of removing the bench bleeder lines and hooking up the vehicle's metal brake lines." At some point, this has to be done regardless of ANY bench bleeding method used or not used. Btw, I have talked to Volvo dealerships that do not bench bleed at all, just install the MC and pressure bleed - they say that will do it all - and furthermore, they say no sequence is necessary, as long as it has at least some logic to it (meaning that you wouldn't just randomly jump around the system). Hey, that's what they tell me, so go figure, no wonder a person wonders what the heck to believe or not to.
KEN C: " The risk is that if the pedal is pushed too far, you can destroy the seal (the same seal that is probably bad and the reason you changed the M/C), so maybe that's why the pedal went to the floor with your new M/C.
MY REPLY: Now after I did the above, I pumped up the pedal prior to bleeding. Haynes says to do that. The pedal firmed up. Then I started the car to see if it would still be firm (because if you a good bit of the previous posts, you will see that I was being told it is possible to not have to bleed the system at all if one is successful in bench bleeding the MC. It was very mushy, so I figured the system has lots of air in it. So, I shut off the car, and pumped up the pedal to get it firm, and then started bleeding last night. LR first, then RR (got too late and dark so I stopped). (Btw, my pressure bleeder is clogged or something is wrong with it. The gauge is acting weird. But the tool can still create pressure, so I will try to finish today. As for you comment about not pushing the pedal down all the way. I had spent booko-mucho hours on the tele with IPD and a very competent IPD guy told me that what that is about is that corrosion get in the old MC and when you push down all the way all that crap destroys the seal edges a bit. The MC has a stroke that can be pushed all the way. I mean if air gets in the system, and that's what can and does happen to vehicles, then you bleed it out. You sometimes discover that by having a pedal going to the floor ...
Your not suggesting people buy a new MC everytime they get too much air in the system and the pedal drops to the floor are you? I wonder how Mechanique did not destroy his MC when the same thing happened to him and he found out that it was convexed/concaved pads.
KEN C: "...open all bleeder screws simultaneously ... This scares me even more than your mother. It's not the right way. You have to follow the proper sequence -- one of the other posts lists it, so I won't repeat it here. Yes, it's tedious, and has you running around the car several times, but it's for the unique dual-triangular circuits of the Volvo, and it's vital.
MY REPLY: Hey, don't shoot me, I'm only the messenger, RTFM - I.E., Read the FAQ at this Volvo web site - THAT is where it is written for three (3) nipple calipers. Don't believe me? Here is a verbatim copy of this sites FAQ on that subject:
" On Volvo models with 2 bleeder screws (upper and lower) on the front calipers, use upper nipple ...
On Volvo models with 3 bleeder screws on the front calipers, open all bleeder screws simultaneously."
and, I might add that there are numerous posts stating that this is all moot when using a pressure bleeder. At any rate, it is not clear at all, whether it is from this sites posts, or FAQ, or written publications, etc. So my plan is LR, RR, RF upper, LF upper, RF lower (both nipples), LF lower (both nipples). Its as logical as anything else I read.
KEN C:
"1) Brake Fluid Flushing Procedures. (From the Volvo Manual] The manual notes that you should DE-pressurize the pressure flusher after doing each wheel ...
2) Then operate the brake pedal several times, before going to the next wheel ..."
MY REPLY:
1) Ok, what is the reason to DE-pressurize after each wheel? No other vehicle manufacture or web site is advocating this nonsense except here. Hey I'll do it if you provide a reasonable explanation.
2) I thought you repeatedly said not to touch the brake pedal? Haynes does advocate doing this before bleeding to remove the pressure and air form the booster and I can understand that, but to do it between each wheel, WELL, THAT HORRIFIES ME, that after I just got the air out of a wheel, I would in essence be pumping air left in the system possibly back to the same wheel I just bled. Makes no sense and I never heard anyone advocate this before, ad I think Volvo needs a newer TSB to clarify a possible typo or explain their logic. I must have called umpteen shops and they do not do this step - they ALL think it is a total waste.
KEN C: Again, pressure bleeding, rather than using the brake pedal, is the best way. Hope you have success. Regards....
MY REPLY: Well, thanks for the vote, but your reply wasn't based on thinking I was doing the pedal/pump method was it? I mean I was fairly clear I said I was using a pressure bleeder.
Thanks for the reply, but I sure wish you would support your reply with reasons for what you are advocating.
diyer
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