brake help

[Elephant_Berls]

i saw there was a ranger forum on here but it dosnt get posted in much so im going to post my ? here.

SO i got a 91 ford ranger 2.3 reg. cab short wheel base truck from my aunt (she got a new one) she suposably just had the brake pads replaced. Well i noticed that when i press on the brake the whole truck shakes. It kinda wobbles to a stop. The brakes have always had good grip and everything it was that wobble that was pretty anoying. Ok so recently (4-5 days ago) i had the brake light and the rear anti lock brake tab light up on my dash. The brake light was on kinda like i left the e brake on (but it wasnt) also i dunno wtf the rear anti lock brake light is. But it was lite up. anyway so its been on for a few days now (i dont feal any pull other than the fact it has a 2.3 and cant get out its own way)

Well today i took the truck for a 100 mile trip and about half way through i went to apply the brakes and they were way too soft. They went all the way to the floor before the truck would stop. This just came out of no where i mean the brakes always would practically throw you in the wind sheild if you barley pressed them. Well i pulled over and i had no idea what to do so i got some brake fluid and pourd it into the brake fluid resevoir. Didnt do any good tho i used a whole bottle. Any ideas on what it could be?

Its odd how it went from very good brake stoping power to almost none at all.

 

[MrShorty]

You were able to pour a whole bottle of brake fluid into the reservoir? Was there any fluid in the reservoir before you started to add? I would guess that 1) you have a leak in one of the brake lines which 2) allowed the level in the reservoir to drop below the sensor which 3) caused the brake lights to come on in hopes that you would check the brake fluid level. When the brake fluid level dropped far enough, air started to get into the brake lines which is why the pedal got all soft and wouldn't stop you.
From here you need to find the leak. Could be master cylinder, any of the lines, wheel cylinders in the rear. Fix the leak, then get the system bled. Master cylinders are required to be "bench bled" before installation, and, I'm not sure, but master cylinder that's had air introduced to it may have to be removed and bench bled as well (assuming the master cylinder isn't deemed the culprit).

 

[Elephant_Berls]

yeh i think it was empty when i added the brake fluid. It was dark so i couldnt really tell. I added about 2/3 of the bottle and it came up to the top so i quit adding.so now its full. So far i dont think its leaked out so maybe it just got too low or something. Is there an easy way to bleed to brake system to remove the air? I may end up having to bring it to midas or some brake shop but would rather not

 

[MrShorty]

There are bleeder valves one each of the wheels and maybe the ABS module. Bleeding the brakes isn't that difficult. A little tedious, but not difficult.
1) Check a manual for any special instructions. If there are none, then here's a generic procedure.
2) Start at the wheel farthest from the master cylinder. Attach a hose to the bleeder valve (looks kind of like a grease fitting on the wheel assembly). Place the free end of the hose in a bottle with some clean brake fluid.
3) Have an assistant press on the brake pedal.
4) While assistant is holding the brake pedal in, open the bleeder valve (turn with a wrench as if you were removing it) and you should get a mix of air/brake fluid come out. When it stops close the valve and have assistant release brake pedal.
5) Repeat 3-4 until no air comes out of the bleeder valve. Periodically check the reservoir and fill with clean fluid as needed.
6) Repeat 2-5 for each wheel.
As I mentioned, I'm not certain if this will adequately bleed the master cylinder. I know that when a new master cylinder is installed, this isn't adequate. But it would at least allow you to get the air out of much of the system so you can check it for leaks.