Bleeding the rear Load Sensing Proportioning Valve

[Jonathan_Ferguson]

As the Load Sensing Proportioning Valve doesn't have a screwable nipple, is the Bolt that sought of points downward do the deed?

 

[inkpot]

Howdy! My 85 pickup does have the normal bleeder nipple on there. I think it is aimed towards the front of the truck. Too dark to see right now, so I will check it in the morning. John

 

[H2o]

picture

can someone post a picture of this setup? i bought my truck with a flatbed and was wondering what that looked like. right now, i just have a rod sticking out of the valve.

thanks.

 

[the truck doctor]

maybe this will help

 

[Jonathan_Ferguson]

 

[Jonathan_Ferguson]

Enlighten me fellas.

 

[ms018kmf]

Mine's slightly different for the year but I've got my bleeder by that part of the LSPV. Both year LSPV's seem to have the other lines running the same. It looks sort of like the red circled part used to be the nipple.

 

[FredTJ]

Mine's slightly different for the year but I've got my bleeder by that part of the LSPV. Both year LSPV's seem to have the other lines running the same. It looks sort of like the red circled part used to be the nipple.

Yup, mines the same.
Looks like the red circle in the photo is the bleeder.
Maybe yours broke and someone simply replaced it with a bolt.
Hard to tell from the photo.




Fred

 

[ms018kmf]

The metal is pretty clean, like what you see when a bolt breaks. Tiny rocks pepper the hell out of parts down there.

 

[inkpot]

Howdy! Mine looks pretty close to that. The red circle should be the bleeder, and the other one is just a nut/plug fitting, maybe for a pressure bleeder, or a check valve? Mine's a long bed, if that might make a difference. John

 

[muiradaker8]

Nice Photos It Is Explaining Me Each And Every Thing In The Photo. Good Photo Graphy.

 

[missouriman]

ok, here is a little brake bleeding thing.

go to the vet's office, get a 60cc syringe. a bit of vacuum tube.
put some grease around the bleeder valve, open and pull out the fluid. you can get a 120cc.. but I find the 60 is easier to pull.
keep the rez full.

 

[forestdan7]

Loosening the bolt lets you bleed out the nipple which should be right next to it, under a rubber cap. This is unlike other bleeders, where the nipple itself unscrews.

I just did mine after replacing the hard brake lines. Bleed LR, RR, RF, LF, master cylinder, LSPV. That should do it.

 

[purerockfury]

Not to pirate a thread, but it's better to keep all of the information
together in one place, instead of starting a new thread.

I have a 93 4Runner. Just replaced the front calipers and rubber
brake lines leading to them. It has new brake lines all around
that are about 2 yrs. old. The passenger front brake keeps
hanging up. It did before and after the new parts.

My question is:
Has anyone experienced the Proportioning Valve sticking?

Thanks

 

[inkpot]

Not to pirate a thread, but it's better to keep all of the information
together in one place, instead of starting a new thread.

I have a 93 4Runner. Just replaced the front calipers and rubber
brake lines leading to them. It has new brake lines all around
that are about 2 yrs. old. The passenger front brake keeps
hanging up. It did before and after the new parts.

My question is:
Has anyone experienced the Proportioning Valve sticking?

Thanks

Howdy! Sounds like you might have a warpped rotor. If not, then maybe a bent spindle or backing plate. the Proportioning valve makes a difference from front to rear, not side to side. I don't think it would be your problem. John

 

[purerockfury]

I forgot to post up that with the new calipers, I put new rotors on too.

There are 3 lines on the Prop. valve. From what I can see, 1 input & 2 output.
Each leading to individual front brakes. That's why I was asking about it,
because of the 2 lines.

Any experience or thoughts?

 

[inkpot]

Howdy! Hmm, well so much for that idea. The block you are describing sounds like it could just be a "T" junction box. Does it have anything else on it like a set screw or adjuster in the middle? Does your rig have the valve under the rear end like the pics earlier in this thread? Check all the hard line to the right front, looking for crimps or bends that were not originally there. Like something that has been moved to make access easier for maintenance. Good chance it would be at a mounting bracket, and that would be hard to see without removing the rubber grommets that hold the lines. Braking pressure in the line is much greater that the return pressure after you release the pedal. Are your calipers "hard" mounted to the knuckle like earlier trucks, or are they "floaters" like Chevies where they can move lefty righty on two large pins. If floaters, then pull the pins and buff them up with some fine sandpaper in case they are dragging. John

 

[rockrash]

Heres my set up.Oh silly me I forgot I took mine off.

 

[ms018kmf]

Brakes can stick if the wheel bearing is a bit loose. If there's a shudder at the sticking brake as it releases then I'd jack up that wheel and see if it can shake.