If you looking to just flush out the old fluid (no air in the system) just crack the bleeder screws, take off the master cyl cap and let gravity do the work for you. Keep an eye on the fluid in the master and top off as necessary(DON`T run it empty). Works gtreat and should only take a little while.

 

I have those speed bleeders, they work good. just make sure you get the right ones, I had to go back 4 times before I could find the ones I needed. ended up getting the rears off Ebay

 

So what are the partt numbers?
Thanks

 

Now I like that. Simple and easy. I think I'll do it that way.

 

This is not a good way to do it. The reason is because brake fluid attracts water. If you keep your master cylinder cap off, the hygroscopic nature of the exposed fluid will attract any moisture in the air. this water will reduce the boiling point, and the entrained water will lead to corrosion of both ferrous and the aluminum internal parts. If you use a silicone based brake fluid, it does compress under pressure, whereas normal brake fluid does not.

 

While this is true, how many folks actually cap the master cyl when bleeding in a normal fashion? Your not keeping the master open for hours on end, this process takes (should take) no more than 30-45 minutes tops.

 

Having to do 90% of my work by myself, or with help that is more hindrance in some cases, I stumbled on the gravity bleeding procedure many years ago.

I fix whatever brake component that I am working on, loosen the bleeder(s),
and do something else while the fluid bleeds itself.

I haven't had to do the pump/hold/loosen/squirt/tighten/repeat business in years.

But, will I get a good flush-out of the system by gravity alone??

 

Nope. The sediment at the bottom of your calipers will just sit there. What I did this weekend was to remove the calipers dump the fluid out and put them back on. I had to take them off anyway to change the brake lines. Lots of nasty stuff in there to cause corrosion on the caliper piston.

 

Gravity doesn't seem to work on this system. It doesn't flow until I step on the brake peddle.

 

Geico266, I hear ya on the sediment/crud and a gravity bleed probably won`t clean out much, if any gunkaroonies, but if you are starting with clean stuff (new or replaced) you can keep it clean by doing a grav bleed, as long as it`s done regularly. As far as it not working, I`ll put a guess on something ABS related causing a no-flow scenario, probably all the turns in the plumbing thru the ABS modulator and/or the way the lines are routed due to the ABS...just a guess.

 

I've always just used the speedbleeders, but I'll have to try the pressure bleeding method next time.

I only have 45K on my truck, and the fluid is still pretty much clear. So it's not too urgent at the moment.

but I agree that brake fluid is the SINGLE most neglected maintenance item. Maybe cooling system is next in line.

 

I've gravity bleed brakes in the past. What I find is that it takes a long time... you wait and wait... go get a sandwich... then find that your reservoir is empty and you'll have to start all over again.

Pressure bleeder gives the best results in the least amount of time. No microbubbles, minimum exposure to ambient air, and a good quality flush.

I think pressure bleeding is the way to go

 

Bringing this one back to life....

 

i m trying to figure a few things out, any help is greatly appreciated.

1st with the speedbleeders, i suck the old fluid with the turkey baster, then fill with new. heres my questions, do i put the lid back on all the way or just set it on top? then open the speedbleeder, for how long, till i see new fluid?

then with the mightyvac, suck out fluid, put new fluid in. lid on or off?
how does it work? i pump the lever till i see new fluid?

i trying to decide which method i want to do and will be easier.
thanks for the help, brian

 

Can someone answer this please.