1. Home
  2. Chevrolet 4x4 Trucks
  3. Brake Bleeding

Brake Bleeding

Hey everyone,

I decided it was time to replace my rear drums on my 1988 Chevy Blazer S-10 4x4 4.3 V6. I picked up 2 drums, 2 shoes, dot3 fluid as well as 2 new wheel cylinders. I'll spare us all of the horror story of the employees at Autozone and skip to the heart of the question.

After replacing 2 wheel cylinders in the back, but also had to replace one of the brake lines from the right rear to the junction block above the rear axle. I blead the back two, got all the air out, and no leaks, and had plenty of fluid in the resevoir -- however I still have a low pedal and a "BRAKE" light in my dash.

It was raining so I had to stop -- my next idea is to blead the fronts, even though I didn't open those and that resevoir never went down. Is this the next logical thing -- err the first thing I should have (after the rears) since I opened up a line?

Thanks, Joe Webster

Reply to
Joe Webster
Loading thread data ...

uh-oh............how long did you have the master cylinder cap off while it was raining ????

Reply to
TranSurgeon
1-2 hours? is that bad?

hehe JUST KIDDING.

It was on 99.99% of the time, and when it was open it wasn't raining :)

dodged that one! Joe

Reply to
Joe Webster

well then, I'd say that either there is STILL some air in it, or you have a connection that is not quite tight enough, and is sucking a tiny bit of air in as you let off the pedal

Reply to
TranSurgeon

I thought that too -- but wouldn't it spray some fluid when I pressed the pedal?

I wiped everything down good and looked as someone pressed away and nothing came out.

Thanks, Joe

Reply to
Joe Webster

Joe,

Poorly adjusted rears will trigger the brake light. You need to make sure the shoes are adjusted properly or the proportioning valve interprets the lack of pressure buildup as major brake problem (hence the brake light) instead of loosly adjusted rears.

With new drums, your best best is to adjust them until you can JUST slide the drums off and on (there should be slight resistance, you want them tight!). Be sure to center the shoe/spring assembley before tightening.

Doc

Reply to
"Doc"

I've found that a lot of times, even this is not enough adjustment... you have to adjust them even a little tighter.

Reply to
Celica Dude

Agreed 100%. I was erring on the side of caution in my advice, didn't want to say "tighten the living piss outta them!" and then have him cook the rear brakes on his first trip.

Doc

Reply to
"Doc"

Thanks guys. I know they wern't dragging as much as I would normally do, I'll give that a try. I'll post back.

Thanks! Joe

Reply to
Joe Webster

I seam to remember this problem... hehe.

I bet my paycheck this is it. I had this same problem w/ my brakes (on a REAL blazer though).

~TLGM/KJ

Reply to
Lonely G-Monkey

I have another question. Is it possible that I have an air bubble in the block that connects to both read lines (above the rear axle). If so, I think the only way that I could get it out would be to bleed ALOT of fluid rather quickly through the system. Is that correct?

Thanks, Joe

Reply to
Joe Webster

"Joe Webster" wrote

No, if you have an air bubble in that location, it will come out when you bleed either rear wheel. When you bleed rear brakes with a single line to the rear axle, you basically bleed the entire circuit through one wheel, and then you finish up the other circuit and bleed what remains in that branch.

Ian

Reply to
shiden_Kai

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.