Originally Posted By: highmilegeguy
My concern is where I see some mechanics pinch off the flexible brake hose to prevent fluid backing up when they open the bleeder.
It seems imprudent to squeeze the brake hose in that manner. Hoses are built tough but it seems pinching them hard with a pair of pliers is a great way to either weaken or damage it. I can't see that technique being a sound step.
On the brakes I've worked on there was absolutely no need for any pinching. The bleeder is a far less "resistive" path than back through the system and all of the fluid comes out the bleeder when the pads are retracted. Try to retract the pads with the bleeder closed, then compare the effort with it open. The difference is night and day, not subtle.
I'm really surprised at the FUD (fear, uncertainty and doubt) rampant in this thread about touching the bleeders. If you're that scared of your bleeders, maybe you shouldn't be DIYing your brakes at all. It's not rocket science - they're there to get bubbles OUT, they are MEANT to be opened and not just in a clean room at a dealer. Whether you open them during pad retraction or not is only one factor of the job but you SHOULD be bleeding fluid regularly and especially after working on the brakes.
Stomp the pedal and if it feels fine do nothing? It takes 5 seconds to do a bare minimum functional bleed to eliminate any bubbles which might be in or near the caliper and remove the most mistreated fluid from the system. I don't understand the lengths some people go to in order to avoid this 5 seconds of work to be certain it's done right. The biggest point of caution while bleeding is not to let your brake pedal go far into "new territory" so that you don't damage your master cylinder seal. Throw a brick under the brake pedal and that problem is solved.
Professional techs may or may not do something because they are paid piece work. If it's faster, then that is how they do it. Plus your car is probably up on a lift, not just jackstands, and getting someone into the car to press on the brake pedal one or two times is a big pain. Furthermore they're usually working by themselves. Don't always take what pros do as the best quality course of action for you or your vehicle - they're there to make money and so is the shop they work for. They'd rather have you pay another piece work fee for a full "bleed" or "flush" and then do it at that time.
I'm not saying that they're acting with malice, just that a for-profit service environment won't always do everything "the best". The owner/manager of the shop will have his own "style" and priorities. Some will pull out all the stops and do everything right, others will cut every possible corner to maximize profit.