Bad Brake Bleeding vs. Badly Adjusted LSPV

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I'm in the process of trying to replace the brake hoses and LSPV on my FZJ80. The brake hoses appeared to have never been changed before because of how badly they were cracked, and the LSPV was leaking so I just went ahead and replaced it. I took it to a local shop in hopes that they would have better luck bleeding it. Today when I went to pick it up, I test drove it and could definitely feel that the brakes were still squishy in comparison to before. The shop is going to take another look at it, and try bleeding it some more and different ways.

I've read a ton of brake bleeding threads describing the horrors of brake bleeding on an 80. However I'm not sure if the squishy brakes are because of air in the brake system? or a badly adjusted LSPV? The LSPV was adjusted to the same distance as the one that was taken off. While this may not be 100% correct I thought it would get me pretty close to the correct adjustment of the LSPV. As far as brake bleeding the sequence I told the shop to follow was RR, LR, FR, LR, and then the LSPV.

My real question is, when the LSPV isn't properly adjusted does the brake pedal feel squishy? Or is the brake pedal feeling squishy a clear sign that it needs to be bleed again?

Any help or knowledge will be appreciated!
 

flintknapper

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As you are aware the LSPV controls how much the rear brakes contribute to stopping the vehicle. Some folks adjust the arm higher (to simulate more weight, resulting in more action from the rear brakes).

The LSPV is sort of the 'high point' in the rear braking system...so it tends to collect air. A spongy feel of the brake pedal is generally air in the system or bulging/old brake hoses.

IF your Cruiser has anti-lock brakes...that is where I would be looking. It can be difficult to remove air from that item. You will need to 'activate' the anti-lock brakes several times, re-bleed, repeat. If that doesn't firm up the pedal feel...let us know.
 
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As you are aware the LSPV controls how much the rear brakes contribute to stopping the vehicle. Some folks adjust the arm higher (to simulate more weight, resulting in more action from the rear brakes).

The LSPV is sort of the 'high point' in the rear braking system...so it tends to collect air. A spongy feel of the brake pedal is generally air in the system or bulging/old brake hoses.

IF your Cruiser has anti-lock brakes...that is where I would be looking. It can be difficult to remove air from that item. You will need to 'activate' the anti-lock brakes several times, re-bleed, repeat. If that doesn't firm up the pedal feel...let us know.
Thanks for the response. So it seems that my issue lies more in the brake bleeding side of things. Therefore a good plan of action would be to activate the ABS several times and then re-bleed the system, and repeat a couple times if needed. I'll communicate this to the shop and see what happens.
 
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You want to go out and buy this, and bleed the brakes yourself.


Plan on going through 2 big bottles of fluid at least.

You can 'bleed' the ABS by loosening up the lines and bleeding a bit out while the system is under pressure.
 
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You want to go out and buy this, and bleed the brakes yourself.


Plan on going through 2 big bottles of fluid at least.

You can 'bleed' the ABS by loosening up the lines and bleeding a bit out while the system is under pressure.
This is actually the other way they are going to try and bleed the system. They initially tried the two person method but that clearly didn't work. Hopefully using the Motive bleeder will push out any air. Hopefully with a combination of activating the ABS system, some more regular bleeding, and then some power bleeding it will get rid of all the air.
 

flintknapper

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This is actually the other way they are going to try and bleed the system. They initially tried the two person method but that clearly didn't work. Hopefully using the Motive bleeder will push out any air. Hopefully with a combination of activating the ABS system, some more regular bleeding, and then some power bleeding it will get rid of all the air.
I've had good luck using the Motive Bleeder. Best to have the correct cap adapter but can be used with the lid supplied. I will take my Cruiser out on a gravel road or find a place with grass...get up to speed (30 mph) slam on the brakes and listen/feel for the anti-lock system to engage. Go back and re-bleed, once more and you should have any air out of the ABS.

Then just make sure to bleed the LSPV a couple of times.
 
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I've had good luck using the Motive Bleeder. Best to have the correct cap adapter but can be used with the lid supplied. I will take my Cruiser out on a gravel road or find a place with grass...get up to speed (30 mph) slam on the brakes and listen/feel for the anti-lock system to engage. Go back and re-bleed, once more and you should have any air out of the ABS.

Then just make sure to bleed the LSPV a couple of times.
What is the recommended bleeding sequence? I've found contradicting post on the forum. The most common recommendation I've found is RR, LR, FR, LR, and then the LSPV; however I have also seen RR, LR, LSPV, RF, LF.
 
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What is the recommended bleeding sequence? I've found contradicting post on the forum. The most common recommendation I've found is RR, LR, FR, LR, and then the LSPV; however I have also seen RR, LR, LSPV, RF, LF.
Just realized I completely mistyped those brake sequences, here is what I was trying to say...

What is the recommended bleeding sequence? I've found contradicting post on the forum. The most common recommendation I've found is Rear Right, Rear Left, Front Right, Front Left, and then the LSPV; however I have also seen Rear Right, Rear Left, LSPV, Front Right, Front Left.
 
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The FSM doesn't specify order but what I've seen most commonly recommended is furthest from MC to closest:
  1. Rear Pass
  2. Rear Drivers
  3. LSPV
  4. Front Pass
  5. Front Drivers

I don't know how the Bypass Valve or any ABS bleeding fits into the above procedure.
 

flintknapper

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Just realized I completely mistyped those brake sequences, here is what I was trying to say...

What is the recommended bleeding sequence? I've found contradicting post on the forum. The most common recommendation I've found is Rear Right, Rear Left, Front Right, Front Left, and then the LSPV; however I have also seen Rear Right, Rear Left, LSPV, Front Right, Front Left.
Typically, starting farthest away from the master cylinder and working toward it is the accepted method. But regardless the order...air is most likely to settle in the LSPV (it being the highest point in the rear system) and it takes either a forceful discharge (bleeding by brake pedal with a helper) or high volume (Motive bleeder at about 15 psi start pressure) to move that air. If you are using clear tubing at the discharge point (bleeder screw) any air will be readily apparent.

But its all an effort in futility if you don't first make certain your ABS unit does not have air trapped in it.

It's not the easiest system to bleed. You just have to make your shop aware of that and offer your apologies.

Show up with a box of donuts and let them have another stab at it.
 
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I have to believe there is another method of bleeding the ABS unit of air...how does the motive bleeder work with our brake reservoir covers?
 
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My vote is for one man bleeding via the "gatorade bottle" method. It moves a lot of fluid quickly with no risk of sucking air back into the system. I do this on all my vehicles at least every two years, no complaints.

As for the ABS there might be another way but I've only used the "gravel road" method.
 

flintknapper

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I have to believe there is another method of bleeding the ABS unit of air...how does the motive bleeder work with our brake reservoir covers?
The Motive bleeder comes with a universal adapter that incorporates a 'hook & chain' method of tightening the adapter on top of the reservoir opening. Our master cylinder reservoirs have a 'push on' cap rather than a screw on cap. The universal adapter works 'OK' but is cumbersome to install and usually leaks if more than 12-15 lbs. psi are applied.

There is an adapter specially made for Toyota type reservoirs. Kind of pricey but works well.



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flintknapper

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I have to believe there is another method of bleeding the ABS unit of air...
^^^^ No doubt there is a way. However IF you have access to a place where you can 'exercise' the ABS unit, you kill two birds with one stone (expel air from the system and physically test the system as well).

It would not be the most expedient thing for a 'shop' to do, but the owner (if capable) might consider this method.
 
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Thanks! Those pictures are helpful as I've been thinking of getting one.

And agree with you on two birds one stone. I was partially asking because I'm interested in the mechanism that allows air to get in there and how doing that exercise gets it out..but if it works, it works!
 
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The FSM doesn't specify order but what I've seen most commonly recommended is furthest from MC to closest:
  1. Rear Pass
  2. Rear Drivers
  3. LSPV
  4. Front Pass
  5. Front Drivers
I don't know how the Bypass Valve or any ABS bleeding fits into the above procedure.

I go RR LSPV LR LF RF and I use a pressure bleeder by myself with a ton of success, the pressure bleeder is the best way to go
 

GSTMike

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I go RR LSPV LR LF RF and I use a pressure bleeder by myself with a ton of success, the pressure bleeder is the best way to go
I just did this in that very sequence after installing some extended lines on Saturday, pressure bleeder makes this a pretty simple task honestly. It's saved my arse on many a clutch slave bleed on my own!
 
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