Hello. My dad and I replaced some calipers. Just the two front. We went to bleed them afterward and it was just dripping, with my pedal to the floor. Sure enough almost zero brakes upon finishing. I hope to god that he put the pads in right. So that is eliminated. He helped me out and has done it hundreds of times. We then moved on to say okay our pedal is not getting pressure, nor are we getting any built up with pumping. It could be the master cylinder, or maybe even the brake booster hose has a bad check valve? We pinched the hose and things seemed to change. So we replaced so far the booster hose, then the master cylinder and guess what... still nothing. Pedal goes to floor and just puffs air when I pump. Never building up pressure. So we have a brake booster on the way. That is going to be replaced next. Are we on the right track? I'm so sorry for this disorganized post. Trying to keep my kids in line while typing this

 

nah nah nah, hang on, your not thinking, it must be those kids hassling you.

You said you clamped the lines and it al changed. That should tell u that the problem is after where you clamped it! If it doesnt tell u that, your brain has officialy stopped functioning :P hehe.

U need to remove the calipers, put them on the bench on their side, and fill the cylinders then put it all bacj on the vehickle, and push the pistons back while theyre on the vehicle but not connected to the lines quite yet. then connect the lines, then do the manual 2 man bleeed procedure.
If you have unfortunately let air get up into the system close to the ABS unit, you will need to buy or make urself a vacuum bleeder to suck the fluid through the system.

I made one using a jam jar, and 2 pieces of hose. one hose goes to a vacuum source on the engine and is safely inserted such that it is only just inside the lid of the jar,( well away from any fluid that u catch), and the other one is smaller (Use vacuum hose) and goes to the bottom of the jar and sucks on the bleed nipple. THis uses the cars vacuum to pul the fluid thorugh. This is the only way i can bleed my 2003 CRV, nbut i can do it on my own and its incredible at it.

The doo gooders will tell u this is dangerous coz u might ingest brake fluid into the car. You simply wont, not unless ur an idiot and cant look at a jar with fluid in it haha.

Obviously, while doing this, ensure the fluid is constantly topped up, the vacuum manages to really pull it all through quite fast.

 

adn sorry i jsut realise,d u replaced the master cylinder as well.
IM affraid that it sounds liek u may nbot know what your doing here, the master cylinder, did u bench bleed it?

ITs ok, dont panic, i can talk you through ti and ther eare youtube videos, but u need to really bleed this particualr master cylinder perfectly.

I can do it out in the jungle in the dirt with minimal tools, and minimal intellectual minds aroudn me to help, oim sure you can do it there

So yeh basicall,y u will likely have contributed another problme by replacing the master cylinder, if u didnt bleed it propperly. if u didnt, uve likely pushed air into the system, down towards the ABS module, in whcih case your going to absolutely categorically definitely need to use the vacuum brake bleeding procedure.

Just take your time, make the vacuuum bleeder, tap the master cylinder out and bench bleed it, bench bleed the calipers, then vacuum bleed the whole lot.

 

Let me rephrase exactly what happened. We did two calipers, that's it. Upon finishing we had absolutely no pedal. When I say "finishing" I mean after bleeding, which we did get brake fluid to come out but it had no bubbles of air so we assumed it was good. ( My car was bled very recently successfully) And afterwards literally had zero brakes. No front or rear brakes. The car wont stop, and all the pedal does is go to the floor. Then, put vice grips on the booster hose on the correct side of the check valve, and pumped the brakes. When the pedal got hard we thought that meant that air was passing that check valve. We did not replace the master cylinder until the brakes were already gone. We then did some research and it said that no brake pressure and no brake pedal pointed to a master cylinder. Which you're right, we didn't bench bleed it. Didn't know about it until reading your post. Thank you for that. But do you think it's possible that it's the brake booster? It's strange to me because my pedal was always VERY low, and I know that it makes it "Harder" to press the pedal down normally when your booster goes out. But there are sources that also say that the booster can cause you to have no pedal or a unresponsive pedal. If we put a new booster in, and that doesn't work we will try your method. Thank you for your reply man. If your method doesn't work however, I think the next thing in line would be replacing the ABS module right? Because sources also tell me that a failing ABS module can cause no brakes / no pedal as well. Let me know what you think

 

But please don't think I missed your point. I hear that the ABS can get air in it and cause this problem too. You're probably right but I sure hope not The master cylinder that was taken out WAS leaking, we can tell by the corrosion below it. So hopefully it leaked into the booster and two of the three parts I buy are correct.

 

nah look its dead simple, the brake pedal will have resistance and stop the wheels without the booster. the booster assist in the pressure by multiplying the force you apply. its out of the qeuestion here. u can bleed a car anad be succesful wihtout the engine ever being on and without the booster ever coming in to action.
U let air in when you removed the calipers, and didnt bench fill them. The air rises up the lines (while the lines drip) and then you end up wiht an air bubble which wants to rise and every time u bleed it manuall,y it jsut keesp rising. u need constant suction on it.
THen you installed a master cylinder and let even more air in.
You are jsut going to have to trust me that ur issue is air, and that yhou need to vacuum bleed it and do it all propperly mate.
Do it, and youl come back here nad thank me !!

 

I believe you. I'll try it. Thank you very much. What you're saying sounds much more sensible. I mean, basically if what I'm saying is correct the booster would have had to magically went bad in the process of putting calipers on. What you're saying is a much higher probability I think. Thanks man. I'll let you know.

 

Last question. Where should I bleed from? Using the vacuum that I buy tomorrow

 

Question, when you went to change the calipers, did you look at where the brake bleeder screw is?
Sometimes people put the calipers in on the wrong side. Left on right and right on left.
This makes the bleeder on the bottom instead on the top. which then prevents one from bleeding the brakes properly.
Bleeding the brake calipers with the like this will keep a bubble of air inside the caliper and never build up pressure.
Hope it is this simple. Good luck.

 

I THINK THEY WERE ON THE BOTTOM. My dad goes " That's weird. Huh." I don't want to be a blame placer, never. Especially not with my dad who's helping. But it's scary working on vehicles with him because he moves way too fast. Thank you. That's going to be what I try along with bleeding using a vacuum since we didn't bench bleed the master.