KRos_+

Well i tried changing the M/C with a used one and got the same problem. So maybe i have 2 bad m/c's.

Brake pedal is soft and spongy and wont build up pressure. No matter how much we bleed. Bled in the right order (FSM) and still no pressure. No fluid leaks no broken lines. Calipers arent dragging. I checked the booster to FSM spec and by pulling and plugging the vaccum line to see for change in idle. No change. Although with the booster hooked up and engine running, the idle drops down while pumping the brakes?? Only happens while engine is warming up. Once the t-stat opens it idles at 850rpms and doesnt fluctuate. Not sure what would cause this.

Looks like im gonna have to drive it like this until next weekend when i can do more testing and repairing as needed. If anyone has any ideas i would really love to hear them. Driving like this isnt safe but i have no choice. I will be studying the site all week so i can know how to test and do everything with the brakes.

Thanks to anyone that will help me!



__________________________________________________

91' Std cab, 5spd 4x4, Manual locking hubs, unknown mileage, all stock......for now

darkmourning

well, looks as if the toyota gods have not smiled on you today, i just typed out a whole how to and i tried to post and everything got deleted and im in iraq right now ready to go on mission, sooooo as soon as i can i'll retype it.

aviator

stay safe dark...

KRos_+

Oh wow thanks for trying to help Darkmourning! And like Aviator said "stay safe"! Post whenever you can.

A little update on whats happening with my brakes:

When the engine is off and i pump the brakes they will build up some pressure but have to go about 2 inches from the floor to actually stop the truck in neutral on a hill.

While driving, i can pump the pedal and build up some prssure and sometimes they dont loess. Other times they slowly lose pressure. And mostly, pedal is about 2 inches from the floor with little stopping power. While pumping the brakes i sometimes hear a loud clunk. Not sure where its coming from.

Any advice Aviator? Or anyone? Thanks YOtatech members!

Support our troops like Darkmourning! My good friend who is doing the SAS on his 92 yota is a wounded Iraqi Veteran with a purple heart!

aviator

sounds like you have a brake line leaking... get it checked! I had a similar issue with my abs light flashing now and then... thought it was related to a ps issue but it was a line going bad... I found out after I hit the brakes and nothing happened... till i hit the car in front of me... fortunately I was only going about 10 mph so there was almost no damage to the bimmer... Don't wait! go to a mech. Now! very carefully!

KRos_+

Well i cant afford nor do i want a mechanic to touch my truck. I dont have a reliable mechanic that i can trust. I would love to take it to a dealer for a couple reasons but like i said i cant afford it.

I have gone over all the brake lines, which look to be somewhat new. Cant find any leak! Im not losing fluid but i do know that a leak could be there and just sucking in air without losing fluid. Im gonna try forcing pressure thru the lines this weekend to see if there is any leak.

Any advice on why it drained my master cyl. when i split the calipers? HAs this happenned to anyone else? They were basically completely extended to contact the brake pads that were totally worn thin. Could that have ruined the calipers?..........Also, my LSPV is pushed up a lot. So that means im getting more pressure to the rear brakes. Could that be causing a problem? I did forget to bleed the LSPV last weekend when doing my pads and swapping M/C's.....Could that be causing a problem as well?

I have to wait till the weekend to do anything about this. So im just trying to find out as much info as possible. And drive as little as possible and very carefully. Any advice is always appreciated!!

This morning it was raining so the roads were wet and all four of my tires locked up while i was pressing brakes to the floor trying to stop slowly. I was only going maybe 20mph. IT was scary! But im wondering how all tires would lock up if there was a leak?

Thanks for the advice Aviator, I respect your words because u have a Hilux LOL!! jk.....its because you seem knowledgable and helpful!

darkmourning

i have some time for the next few days to relax a bit. why did you split the calipers? you dont have to do that to change the brake pads on toyotas! you probably did further damage when you split them.

darkmourning

also, you didnt bleed it right if your PV is sending more pressure to the rear, try to see if you can get your hands on an air compressor and a vacuum bleeder, thats how i would do it in the shop when i worked for toyota. go RF,LR,LF,RR. or you can pressure bleed it with a friend, it will take a lot more time, but make sure you do it right. all else fails, get it into a shop seriously, brakes are nothing you wanna mess with unless you know exactly what youre doing, otherwise you'll do more damage than good. like splitting calipers.

XtraSlow_XtraCab

First off, welcome to YotaTech!

What Darkmourning said stands true. You've probably damaged the seals on the calipers if they weren't so already. Did the caliper pistons come out of the cylinders?

My main suggestion would be to rebuild all calipers and wheel cylinders anyway. Check where the master cylinder bolts to the firewall (pedal/interior side)... is there a sticky residue and perhaps peeling paint? If so, this is generally the tell-all sign of a bad master cylinder and can be applied to all vehicles with hydraulic brakes/clutches... not just Toyotas.

If the truck has any suspension modifications to the rear (cheap lift kit) and the proportioning valve has not been adjusted to adapt to this, you will lose a LOT of braking power. A suspension lift will "fake" a lighter load and allow less braking power in the rear. All the BPV does is measure the distance between frame and axle, via a cheap little rod that is probably horribly bent (depending on previous owners) and regulates brake pressure feed.

Have you bled the brakes AT the master cylinder itself?

Tighten the drums. We all have different methods, but I "crank" the shoe adjusting gear until I can only spend the tire 1.5 turns (brake off). Works for me.

But your main thing is finding the air stuck in your line and remedying any leaks. Regardless of what I said before... there should be no pumping required.

BTW

In case you were wondering what the "true" oil pressure of a 22R(E) is... they read about 75-80psi cold at a high idle (~1700 RPM). ~25psi at hot idle and 45-55psi hot high idle. And as stated before, stock gauges are junk... 1984, 1994 all junk. (I used a mechanical gauge for about a year when I suspected this.)

Good huntin!

KRos_+

Thanks again Dark! I am going to try and change the master cylinder with one form a junkyard that guarantees it will work. (they test everything they sell prior to selling). Then i will also try and get ahold of a vacuum bleed kit. Hopefully i can rent one from somewhere so i dont have to buy one. And i will go from there.

I guess I should have read the FSM on changing the brakes before i split the calipers.....my mistake. I now realize i could have just taken the 2 caliper mounting bolts off the backplate and compressed the pistons with a clamp to make room for new pads. Put pins back and slid the caliper back on 2 bolts and bam done. But i have always learned things the hard way ..........Although the brakes seem the same as before except a little more stopping power due to new pads. So im praying that i didnt damge the calipers! Is it difficult and/or cost effective to rebuild them myself? I have 2 spare that i could rebuild before i take mine off. If its worth it.

Also, my LSPV is bent up, opening the valve for more pressure in rear. Should i bend it to where it should be?? WHich from what ive read and seen here at yotatech is straight in line with the frame rail. Im guessing my shoes are worn thin since there has been more prssure to rear(for who knows how long) and looking at condition my front pads were in. Could that be causing problems as well? I plan on checking EVERYTHING more in depth this weekend.....and if i cant fix it i will take it to a shop and go even further in debt!! Last resort.

Thanks to anyone that can help. Im just trying to get as many ideas as possible so i can figure it out this weekend and fix it myself, cost effective and done right!

ANd thanks again Dark! Enjoy your couple days of relaxation!

darkmourning

no prob. it's not hard to rebuild calipers, but the time and money you would save buying loaded ones would be much easier. and how is your PV bent up? is the line bent? cause you may have just found the answer to your problem.

KRos_+

Thanks for the info and advice Xtraslow! We must have been posting at about the same time last nite lol! I posted then went to bed

WHen i split the calipers i noticed 2 little rubber o-rings(seals). On one caliper one of the rubber seals was a little chewed up so i replaced it with one in better shape (off the spare). THe pistons did not come out of the cylinders and the boots looked good. My passenger side caliper looked new (had a sticker on it still legible and shiny pistons). Drivers side looked older but still in decent shape, pistons and seals and boots all looked good. Ill check the firewall by the pedal for sticky residue. I didnt notice any while checking pedal height and pushrod. The master cylinder bolts to the booster which then bolts to the firewall, should i look around the pushrod that goes thru the pedal and into the booster thru the firewall?

My truck is all stock so no lift. If anything the springs are sagging, which is causing the PV rod to be pushed up like there is a load in the rear. Like Darkmourning said that may be my problem! I will bend that to where it should be (as close as i can get it) this weekend and then try and bleed everything. After i tighten the drums and check over everything else again.

Yes we did bleed the master cylinder to FSM specs. Which seems strange to me but we did it. With it in the truck disconnect the 2 lines pump the pedal 3-4 times and hold while someone plugs the rear hole with their finger. Repeat until no air comes out. Thats what it said in the book.

So would it be more cost effective to rebuild the calipers? Rather than buying new loaded ones. Im on a budget but i want everything to be reliable, not cheap and easily broken. I dont mind it taking time.

I just cant wait to do some muddin! But its not ready yet Im getting ready to move at the end of the month and all my money is going to that.

Ill try and post some pics tomorrow after work of what my PV looks like........Im tired and rambling! goodnite yotatech lol

Thanks a lot you guys! I really appreciate the help!

KRos_+

Well its been a busy month for me. Between moving and the heat waves and brthdays. Finally i get a weekend to work on my truck! (hopefully!)
I still barely have any brakes but i can stop and lock the rear wheels up. I havent been able to do anything to my truck in the past month! And that has made me angry! But im living in a nicer apartment with my wonderful girlfriend whose birthday was yesterday! And we both are working more so have money to do much needed repairs/upgrades.

My plans this weekend include: replacing one used front hub along with rotors(both sides) and balljoints (new hub side) , Inner tie rod end, put on NEW Master cylinder, Drain and fill tranny with MT-90, Drain rear diff and fill with 85w90 gl5 since i cant find 90w anywhere!

When i get all that done im gonna call Dealership to get the new steering rod for free (recall!). So im hoping to get a free alignment as well. Not sure if they will have to do an alignment after they replace the steering rod and everything.

Ill post back soon and keep this thread going, Im loving my truck but it needs to be fixed! Oh and i finally got some decent tires put on!! BFG Long trails on front ALL terrains T/a KO on rear, 30x9.50x15, Rides smoother now! GOtta love craigslist!!

KRos_+

Finally! I got my brakes fixed! Turns out it was the master cylinder. I ordered a brand new one (w/ res and sensor cap) from ROckauto on sale about a month ago, and i just put it on earlier today. We then bled the system and bam i got brakes again! It took a few times to bleed eveything but we worked all the air out and now the brakes work great! Stopping on dimes!

I also changed the pass side inner tie rod end because the boot was basically gone and it was very loose. Now ill have to get that alignment soon. Still i want to change out the hub and do the ball joints before then, but we'll see.

Doing an oil change and replacing radiator drain petcock 2morrow. Petcock leaks slightly i think its just the little rubber o-ring on the end is probably bad. It drips out the drain tube after i shut off engine. I picked up some Valvoline 10w40 to see if that helps my oil pressure at oper. temp. Gonna go with a PUrolator filter.

I had good intentions for the past 2 weekends to get some things done on my truck, but with this heat (90s and 100% humidity) things seem to take longer. Plus they dont always go as smooth as hoped. But im getting there and everything else is still working good, so im happy.

Thanks to everyone that has given me advice on these matters! Its why my truck is still on the road! Even though Id love to take it off-road, Im not sure its ready yet! And since its my only vehicle, im kinda thinking maybe i shouldnt. Any advice on that matter?? LOL

john4wd

@ local walmart they have
1. Delvac super 1300 $12.96 a gal 15w-40 with 1380 ppm zink dino oil
2. Rotella tripple protection 13.79 a gal. 15w-40 & around 1200 ppm zink dino oil
3. Rotella t-5 $16.00 a gal. synthetic blend around 1200 ppm zink synthetic blend oil
4. Rotella T-6 $21.36 a gallon 5w-40 around 1200 ppm zink full synthetic oil

@ Auto Zone has same as above oil but cost way more!!!!
An example of price difference 50/50 prestone is $14.99 & at walmart it's just under 10
bucks, used to be 8 bucks at walmart a few months ago.
Bought Medium blue thread locker at walmart $4.74 while at AZ it's almost $6

I go to Wal Mart Auto Section 1st, Then other places 2nd and so on!!!!

AZ also has:
1. Valvoline Premium Blue 15w40 & 1314 ppm zink dino oil, had no price tag.
2. Rotella T-1 SEA 30 weight straight dino oil, ???? on the ppm Zink forgot to get price.


older specs of CI-4 and CH-4 have higher levals of zink
read to stay away from newer CJ-4 said has less levals of zink
read not to go above 1400 ppm zink
Would anybody use these? I'm leaning toward WM number #4!!!!