i have a 1990 toyota pickup 3.0 automatic 4x4. when i bought the truck the brakes were not the best meaning at that time it didnt have alot of pressure. my buddies and i went 4x4ing one weekend we were going do the side of this mountain, a simple trail, for about 45min. we were in descent when i keep having to pump the brakes to keep pressure intill one time i did it hit the floor. driving it back i had to limp it in use the hand bake no pressure at all. since then ive replace the master cylinder and blead the brakes including the preportioning valve but i still dont really have much. i read something about the abs relay dont really know anybody can help i would appriciate it.
loss of brake pressure
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when you push the brake peddle does it slowly drift, or is is really soft? if its just soft it is possible that you did not get all the air out of the lines, or the rubber lines that go to the front calipers could be close to blowing. They will swell under pressure. If you peddle slowly drifts to the floor it is possible that you have a bad master cylender. Even new ones can be bad. Have you checked your rear wheel cylenders to make sure they are not leaking? If you front pads are frozen in the calipers that will also cause a low peddle. make sure the pads move easily. hope that helps a little.
IMO...it sounds like there was a poor bleeding job
Did you bleed from the master cylinder first when you replaced it? Make sure you bleed from the master cyl. first and then start from the RR tire, then LR, FR, and then FL
try to get a bleeding kit with a clear tube that connects to the bleeding screw so that you can visually see the air pockets come out and keep bleeding till you see NOTHING but fluid come out of each line.
And while you are at it check your wheel cylinders.
Hope you get it fixed. Brakes are not something that you wanna do wrong.
Did you bleed from the master cylinder first when you replaced it? Make sure you bleed from the master cyl. first and then start from the RR tire, then LR, FR, and then FL
try to get a bleeding kit with a clear tube that connects to the bleeding screw so that you can visually see the air pockets come out and keep bleeding till you see NOTHING but fluid come out of each line.
And while you are at it check your wheel cylinders.
Hope you get it fixed. Brakes are not something that you wanna do wrong.
when bleeding the master cylender you just take that plug out that is between the two hard lines and let it drain ive never bleed a master cylender ?then i start at the proportion valve then the rear then the front?
did what was said but when i pump the brakes there is a sqeaking noise out back could that possibly be the wheel cylenders and could that have been the problem all along
you should perform a rear brake adj and then bleed the brakes but the pedal loss could only be a leak or a bad master.
also dont forget to bleed rr lr lsvp then rf lf
well heres the thing i took the drum off the back right and there was i drop of fluid on the bottom of the wheel cylender if it was to leak how much would be there
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Probably about a drop. If it's not bone-dry, it's leaking and needs to be fixed. If only one wheel cylinder is leaking, replace them both or the dry one will leak as soon as you replace the leaky one.
thats kindda what i figured when it came to the amount of fluid. i figured ill replace both the life is probibly going to be the same and it will probibly increase in pressure they are cheap anyways while i have them off i might change the shoes as well being thats going to be part of the task of changing the cylenders. i had one person tell me bleed lr rr fl fr and anoughther tell me rr lr fr fl. i figured it would be best to start at the proportioning valve first acually the master since i didnt do that when i replaced it.
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In my experience, disc brake calipers are less likely to leak than are drum brake wheel cylinders. But, you do have a truck which is nearly 20-years-old, so when you get your rear brakes all figured out, take a good look at the fronts also. Don't neglect looking at the brake soft lines either -- they are cheap and easy to replace as well. And, if you don't have one already, consider buying a flare nut wrench (10mm, I think).
The correct order is LR. RR. RF. LF. You always bleed the farthest from the master cylinder first, in many cases that would be the RR, however on our trucks the brake lines run under the hood to the passenger side and down the passenger side frame rail, then it has to cross back over to the LR, that makes the LR the longest line and therefore the first to be bled.
i guess that makes scense. i will probibly do the hoses as well if i can get them im in the virgin islands and things are usually a couple day wait ive checked on the cylenders at a little mom and pop place they have them is there going to be a difference in lx compared to ls models
so i changed my cylenders and i pop the hood to see most of the brake fluid was gone i pulled the master off because i didnt bench bleed it and there was fluid in the cup of the booster i guess it was leaking out the back of the master so does that mean that the new master cylender i just put on is screwed
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