Not sure what a frame code is, but can confirm this is the cheapest model you can buy (4cyl & 15'' rims) and was discontinued in 2000.
What is this thing? [SOLVED - Load Sensing Proportioning Valve]
- Thread starter quatin
- Start date
Not sure what a frame code is, but can confirm this is the cheapest model you can buy (4cyl & 15'' rims) and was discontinued in 2000.
Adjust the fluid pressure by changing the A or B length.
1. Low pressure - Lengthen A, B
2. High pressure- Shorten A, B
HINT: Fluid pressure change for one turn of the lock nut is 100 kPa (1.0 kgf/cm2, 14 psi) and fluid pressure change for 1 mm (0.04 inch) sliding of the adjust bolt within the long hole position is 40 kPa (0.4 kgf/cm2, 6 psi).
Initial set length (Unladen): 222.5 mm (8.760 inch)
I can't see the pictures. I'm searching all over the net for how to adjust this thing, so it would be really helpful if you can reupload it.
TheDurk
Elite Member
Here you go...
96RedRunner
Senior Member
Knowing code will help when buying parts, B-pillar driver side ID tag tells you.
Mine is VZN185L-GKPZKA, VZN185L is frame code, GKPZKA is characteristic code.
Thanks. What is the unladen distance you quoted earlier? I couldn't find that in the manual you posted.
Is my valve just broken? I feel like the default state should be with the spring fully loaded and the arm down. My default state is with the spring fully relaxed and the arm up. When I pull down on the bumper (adding a load), it seems like the arm wants to go up, which can only work if the default state of the arm is down.
Default state (unladen) with spring fully relaxed and just hanging loosely. Arm all the way up.
What I think should be the unladen state, with the arm all the way down and the spring fully loaded.
Default state (unladen) with spring fully relaxed and just hanging loosely. Arm all the way up.
What I think should be the unladen state, with the arm all the way down and the spring fully loaded.
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TheDurk
Elite Member
That wasn't me. And I have never seen one of these; except I was looking for one on mine many years ago because of the manual. I have ABS, so I never found it.
Nate_GB
Member
The parking brake and the hydraulic braking system are completely separate systems all the way up to the point of the actual brake shoe engagement inside the drums. So the fact that you say that parking brake use effects the situation leads me to believe that the brake shoes inside the drum are not installed correctly. There's lots of adjusters and springs and small parts that have to be in the correct place to function properly. I'd be willing to make a heavy bet that's where your problems lie. I'd start by removing your drums and comparing what your setup looks like to a known correct setup photo.
Post a photo of each side with the brake drum off and we should quickly be able to tell you if something is way off.
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19963.4lsr5
New member
There is a special procedure to adjust the ebrake bell cranks which effect the brake shoe adjustment.
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
It might take me a bit to get the car jacked up to take pictures, but meanwhile I have pictures of the drivers side drum before I started disassembly. At this point, it is all original parts, except for the wheel cylinder. (had the problem before replacing wheel cylinder too) To replace the wheel cylinder, I popped off the c-clip for the adjuster arm and pulled it off the pin (but didn't remove the spring) to make it easier to turn the adjuster to max so I could slide the cylinder off. I adjusted the shoes after installation.
Some things to note. This problem isn't exclusive to the e-brake, it's just easily reproducible using the e-brake. The old shoes had plenty of meat left, but had more wear on the bottom where all the dust gathered forming a 2''x2'' sticky patch on the shoe facing the rear. Maybe the 1 shoe was getting stuck? I also never adjusted the e-brake as the shoes wore, so it would take 10-11 clicks on the e-brake handleto set. After the new shoes, it takes 5-6 clicks.
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Do you happen to know where to find that info? I've been googling all around and can't find the specific procedure. There's a nut inside the parking brake lever, plus there's a bell crank on the outside of each drum.
96RedRunner
Senior Member
Page BR25 of FSM
Adjusted the bellcranks tonight so I took some pictures. I didn't see anything out of place, but could use another set of eyes. I also notice my new shoes has some funny wear marks after 30 miles of driving already. I can now feel some light grooves in the drum that I'm not sure were there before. Guess I have to go get new drums or have them turned.
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Nate_GB
Member
Are those grooves worn in the new brake shoes or just streaks? The hardware looks to be set up properly from what I can see. The way I usually adjust the rear brakes is to turn the adjuster with a flat head screwdriver through the backing plate until there is just the slightest amount of drag on the drums. Assuming the brakes are setup properly, are you getting good fluid flow through the bleeder valves while bleeding?
Those are streaks. I do the same thing on adjusting the drums, then I pump the hand brake until I don't hear the automatic adjuster clicking. I did get decent fluid flow eventually when I bled the drums. I have a brake bleeder hand pump, but we had to try the pump the brake pedal method a few times to get things going. (again a sign of a tripped valve?) I did notice the LSPV bled much easier than the wheels. I feel like the calipers bled easier than the drums too.
Update:
Replaced drums: No effect
I pulled the LSPV valve off and it appears the piston (red rod thing) is seized. I would assume some type of spring like response from it, since it is connected to a lever with the load spring. There's about 1/8''-1/4'' of play on the piston, but you need to press/pull hard. Once it's in, it stays in, once it's out it stays out. There's also a bypass valve that somehow rides ontop of this piston, so perhaps that part is seized too? Seems like I need to replace it regardless, so hopefully this is my problem.
Replaced drums: No effect
I pulled the LSPV valve off and it appears the piston (red rod thing) is seized. I would assume some type of spring like response from it, since it is connected to a lever with the load spring. There's about 1/8''-1/4'' of play on the piston, but you need to press/pull hard. Once it's in, it stays in, once it's out it stays out. There's also a bypass valve that somehow rides ontop of this piston, so perhaps that part is seized too? Seems like I need to replace it regardless, so hopefully this is my problem.
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Final update. Replaced LSPV and problem resolved. I'm still unsure how the system works, because even with a new valve, the lever is in a permanent up state, so I don't understand how it's supposed to adjust load, when a loaded chassis will make the lever go up even more?
Anyhow, for anyone replace theirs, remove the spare tire first or you can't see the brake line coming from the MC. I cross threaded the fitting for that brake line working blind. I had to chase it down with a die cutter. Turned a 20 minute job into a 2 day job.
Anyhow, for anyone replace theirs, remove the spare tire first or you can't see the brake line coming from the MC. I cross threaded the fitting for that brake line working blind. I had to chase it down with a die cutter. Turned a 20 minute job into a 2 day job.
cejaslocas
New member
Quatin,
I know this thread is a few months old. I was wondering if you could provide the part number for the LSPV you replaced. My 2000 4Runner is having the same problem. But looking online, my LSPV looks different than the others I see out there. Yours is the only one that looks like the one I need. Hope you remember. Thanks in advance!!
Rear Brake Proportioning Valve
reviving an older thread. I have a 1999 Toyota 4runner 2wd base model with the Rear Brake Proportioning Valve . my 4runner is lifted 2.5 inches and ive read that lifting a base model will cose the brake light to turn on and off. is there a way to fix this besides from pulling the light fuse? just kinda of annoying to see the light pop on and off lol.
also anyone tried the Revtek Rear Brake Proportioning Valve Relocate Kit for 1996-2004 Toyota Tacoma to fix this problem?
reviving an older thread. I have a 1999 Toyota 4runner 2wd base model with the Rear Brake Proportioning Valve . my 4runner is lifted 2.5 inches and ive read that lifting a base model will cose the brake light to turn on and off. is there a way to fix this besides from pulling the light fuse? just kinda of annoying to see the light pop on and off lol.
also anyone tried the Revtek Rear Brake Proportioning Valve Relocate Kit for 1996-2004 Toyota Tacoma to fix this problem?
Sorry for such a late response. For future reference:
47900-35493 Pressure Metering Valve
$260 part and no aftermarket that I could find since it's rarely installed. I was able to revive the old valve by playing with the piston, so I kept it as a back up just in case.
