i think that when the tread was originally started wilwood only made a bubble fitting for their proportioning valve and later made one with a double flare.
Write-up: Toss the LSPV and install a manual proportioning valve (2 Viewers)
- Thread starter jcardona1
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i think that when the tread was originally started wilwood only made a bubble fitting for their proportioning valve and later made one with a double flare.
i dont remember why i kept the sense line i think that it had to run back to the abs since i kept it. going through the abs to the pv to the rear was because the lspv was taken out so a manual valve was installed to take its place. i dont have a diagram and i sold the truck to a friend so i cant get pics or take a look easily. i did post a few pics from when i installed the t so that may help a bit
Could be. The one I got came from 'FlyinMiata' and they just include adapters. You discard/don't use the ones that come with the unit and install their adapters.
i think that was the one that someone was able to track down with the double flare fittings. if you make your own lines insted of buying the factory lines use the nicopp lines Amazon product ASIN B01801G45A
Toyota brake lines are 4.75mm OD and the fittings have a M10x1.0 thread. The flare is "double flare" also called "inverted" flare. The fittings on the left are on all the misc hardware (LSPV, tees, elbows, etc). The fitting on the right is on the master cylinder and ABS unit. They will leak if interchanged (so I read).
^^^^^ Expand above.
Looking and this pic (and statement) I 'think' the issue (with respect to leaks) involves the two different brake line 'nuts'.
The one on the Left is for a Double Flare (M10 x 1.0 thread). And as far as I know is the only one used (at least on my model).
The nut on the right is for a 'Bubble' Flare....and would indeed leak with a double flared brake line.
A 'Double Flare' nut will have a concave recess (45°) for the flare to 'nest' in.
Because most 'Bubble Flare's have a 90° base.... the corresponding nut is also 'flat/90°' to accept it.
Double and Bubble Flares:
Yeah, I bought a bulk line kit just to have everything on hand in case I choose to make some lines or screw up the factory ones.
toyota only uses a double flare for the lines. there are two different style nuts, one is a longer nut and the other is shorter. ive used them interchangeably and have only had a line leak was if the flare wasnt fully formed or nut not fully tightened. from my experience it dosnt matter which one you use
I'm going to look carefully on mine when I take it apart and note any differences. Not in a hurry with this. I am going to start with taking pressure readings (as they are now) at all four corners, then compare to the finished product. I checked my vacuum this morning to be sure my booster is able to work well. It was fine.
Just documenting (for my own purposes) the 'mod'.
alia176
SILVER Star
Flint ,
I love your approach, as it is methodical and repeatable. I did buy the correct pressure gauge to measure the brake fluid pressure at each caliper so I'll follow suit.
I love your approach, as it is methodical and repeatable. I did buy the correct pressure gauge to measure the brake fluid pressure at each caliper so I'll follow suit.
Malleus
Far west of Siegen
This is exactly what the FSM says to do. I've never done it because I'm lazy. One day when I really have nothing in the way, I'm going to cobble together a set of gauges and a manifold and do it properly.
@Malleus Wrote:
This is exactly what the FSM says to do. I've never done it because I'm lazy. One day when I really have nothing in the way, I'm going to cobble together a set of gauges and a manifold and do it properly.
^^^^^
Haha.....I'm not too lazy to do the work, just too lazy to read my FSM on it.
This is exactly what the FSM says to do. I've never done it because I'm lazy. One day when I really have nothing in the way, I'm going to cobble together a set of gauges and a manifold and do it properly.
^^^^^
Haha.....I'm not too lazy to do the work, just too lazy to read my FSM on it.
Took pressure readings at all four corners today (old system). I rebuilt the rear calipers a year or so ago but everything else (except brake booster and some rotors is all original to the vehicle). So definitely in need of freshening up.
I started by sitting in the drivers seat and pressing on the brake pedal to a spot I thought represented a normal 'easy' stop (in town driving). I then measured that distance from the pedal to the floor mount on the seat so I could establish a fixed distance for repeatable pedal pressure.
Found a telescoping rod in my shop and adjusted it to fit. That way I could press the pedal...lock in place and then go read the brake fluid pressure at each caliper. I just want a 'before' reference to compare to the 'after' mods results.
Front Left:
Front Right:
Left Rear:
No pic of the Right Rear (Gauge was at an odd angle, but it was about 50 psi less than the others)?
Rear Rotors looked fine, fronts had just a little wear (a tad under 32mm) which is full thickness. So I will take them in and have them turned to true them up and provide a good surface for the new pads.
Then it is on to replacing parts and doing the ABS/LSPV delete.
Will be installing a new Master Cylinder, New pads front and rear, New front calipers, All new braided soft lines. Will be removing the ABS wheel sensors and plugging those holes with the Wit's End kit for that.
I started by sitting in the drivers seat and pressing on the brake pedal to a spot I thought represented a normal 'easy' stop (in town driving). I then measured that distance from the pedal to the floor mount on the seat so I could establish a fixed distance for repeatable pedal pressure.
Found a telescoping rod in my shop and adjusted it to fit. That way I could press the pedal...lock in place and then go read the brake fluid pressure at each caliper. I just want a 'before' reference to compare to the 'after' mods results.
Front Left:
Front Right:
Left Rear:
No pic of the Right Rear (Gauge was at an odd angle, but it was about 50 psi less than the others)?
Rear Rotors looked fine, fronts had just a little wear (a tad under 32mm) which is full thickness. So I will take them in and have them turned to true them up and provide a good surface for the new pads.
Then it is on to replacing parts and doing the ABS/LSPV delete.
Will be installing a new Master Cylinder, New pads front and rear, New front calipers, All new braided soft lines. Will be removing the ABS wheel sensors and plugging those holes with the Wit's End kit for that.
Did you get any further in this?
I'm contemplating deleting the ABS/LSPV. I've over(under?) adjusted the LSPV and burned down my rear pads way too soon. Plus my rear passenger caliper is wearing down pads way faster then my rear driver so I figured while rebuilding those, might as well go the full way.
Yes, been waiting on some parts and also trying to find time to devote to it. Have several other things going on. But I am documenting my progress....so will be able to contribute that here (if anyone is interested).
Since all of my system was pretty much original....I decided to just go through it all and freshen things up. So....I've got a new Brake Booster, New Master Cylinder, New Front Calipers (rebuilt the rears just a couple of years ago. All new soft lines (braided Stainless Steel).
Have removed the ABS unit (and sensors) and LSPV. Plugged the sensor holes with Wits' End sensor plugs. Of course all new pads and rotors turned. New Wheel Bearings. Installed a manual Proportioning Valve. Hopefully have time to get the system bled this weekend and try it out. Then I want to compare pressure readings at all four corners to what I had before I started.
1973Guppie
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stop debating and just DO IT. It is a much better setup on a modified rig to have all that crap removed especially when it's not working correctly.
Just finished taking my LC out (ABS and LSPV removed) to bed in the new brake pads. After a few hard stops I could tell the pads were seating. Took the Cruiser off on one of our ranch roads to do some 'skid testing' in order to adjust the Manual Proportioning Valve. Got it pretty close now, but will readjust after I've driven the vehicle some more.
My first impression is that I can't believe I've been driving along all these years with sub-par brakes (and that's being charitable).
It will flat lock up all four tires now (if I want to). I grew up without anti-lock brakes....so I am familiar with how to apply brake pressure during a hard stop. I am NOT advocating anyone remove the engineered features on their vehicle. I will simply say this: On MY vehicle a combination of old soft lines, a less than perfect ABS module and an older Master Cylinder had left me with brakes that had reached a point of concern.
Yes, replacing pretty much the entire brake system would have/should have returned braking to what it was when I got the vehicle (at three years old). But for what I use my vehicle for.....modifying the system to more closely replicate one before ABS existed is more to my liking. It will definitely stop now.
Ironically, I can't drive it though until I get one little rubber cushion. When I got out of the vehicle I noticed my rear brake lights were on. I knew I had the pedal adjustment correct and the booster rod adjusted. On the floorboard I spied a few small pieces of hardened rubber.
Looked up under the dash and could see the rubber cushion that sits between the brake pedal lever and the brake light switch had crumbled. When this happens the brake light switch is not depressed fully (its a normally open switch) so your rear lights will remain on even with key off. If you don't notice this....your battery will drain overnight.
The switch itself has a range of adjustment....and a person could adjust it enough to make the lights go out, but it isn't worth cramming yourself up under the dash to do so. Just replace it.
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alia176
SILVER Star
This is great news Flint. Do you think the proportioning valve is needed for your application? It's prolly hard to tell how you have biased the valve but I'm curious.
lumbee1
Native American
After replacing my booster, my rubber brake pedal cushion also fell apart. I installed a new one but did not adjust the switch itself. This caused the brake lights to activate and the transmission to drop out of lockup.
I can't say conclusively just yet. I keep about 350 lbs of tools, etc....in the back of my Land Cruiser at all times so my LSPV was adjusting for that already. The little bit of testing I did with the proportioning valve this morning was on dirt, gravel and grass.
With the valve fully open (spring pressure actually)....the rears definitely locked up before the fronts on gravel and grass. On hard pack dirt it seemed it was a good balance. I haven't had it on pavement yet.....so can't say what the final adjustment will be (if any) at this juncture. But I promise....I will post back here when all done.
I like having the ability to adjust the rear brake participation.....whether I ultimately use it much or not.
alia176
SILVER Star
