Endless brake bleeding - And how to fix it (1 Viewer)

[Vision19]

Hello all,

I have been very grateful for this forum and the resources it contains. I purchase a 94 LC several months ago and have been learning a lot since then. I recently replaced every hard brake line on the body/frame and all of the soft lines, as well as the LSPV. I thought I would share my bleeding experience with others in case any one else gets stuck. This procedure is for systems with ABS.

With all new lines, there is obviously a lot of air in the system. I had my wife help me with pumping the brake while I bled. I did it in the following order: LSPV, RR, LR, LSPV, FR, FL.
All seemed to be going except I could not get airless fluid out of the LSPV, and I could hear the "tink" of air/fluid in the lines. After hours (5-6) of bleeding, I decided to try something else. I used a air pump needle (like you would use to fill a football) and stuck it in the lid of the fluid reservoir (you have to take off the small cap on top and the little plastic piece inside the lid). I then used a regular air nozzle and regulator to put about 10PSI of pressure on the reservoir. Then my wife and I continued our bleeding procedure, starting with the LSPV. After about 10 pumps we got an enormous amount of air out of the line. I believe the long return line along the frame that goes to the ABS unit was harboring the air, and we could only siphon off a few bubbles at a time without the extra pressure. The total bleeding then only took about 7 minutes. I believe I was able to get all the air out of the ABS unit as well.

Hopefully this info can save someone a lot of time and frustration.

Cheers

 

[elhombre]

Two people working for 5 hours means you would have payed yourself $5/hour. Sometimes it really is better to bite the bullet and buy a tool that will make a job so much easier and faster. Glad you got it figured out.

Amazon product ASIN B0002KM5L0

 

[jpoole]

$55 is totally worth it for a pressure bleeder setup, especially if the cap adapter fits the 80 reservoir. If you don't want to pay $50 though and like to build things you can drop by your local hardware store for a pump sprayer, a pressure gauge and a few plumbing fittings (the black flexible pipe couplers/caps can be adapted to fit the MC reservoir) then make your own. I went this route and it's worked well for many full flushes as I've tinkered with the system a lot over the years.

In any case I agree that you want pressure bleeding plus I like to add a few brisk pumps of the pedal for each bleeder. I also loosen each line on the ABS unit while the system is under pressure to bleed those a bit as well. Not sure it makes any difference but I've usually spilled a bit of brake fluid anyway, somehow, so have to rinse the area anyway and figure I may as well bleed more. I often do this ABS bleed last as I'm trying to run the rest of the fluid out of the pressure tank and get the reservoir level low enough to pull the pressure bleeder off.

Another reason to dial your setup in is that you really want to do this every 2 years or more frequently. It's also nice to be able to re-flush / bleed easily if/when you need to open up any part of the system.

A final note on bleeding that may be interesting is a recent discovery that I made on how the LSPV flows fluid while being bled. Out of curiosity I pulled my LSPV last week and bench tested the fluid flow paths at low/bleeding pressures. This may be common knowledge but I found that the pressure line for the rear circuit goes fully to the rear brake calipers when the system is at rest. The bleeder port is tied directly to the 2nd line (some call it the return line). This means that to bleed the primary line from MC to lspv you have to bleed the calipers and to bleed the secondary line to the lspv you open the bleeder. Per my bench test there was no crossover between these two pathways at low pressures and I don't think that the lspv starts to balance/reduce rear brake pressures until there is enough pressure in the system to actuate the valving inside. I was wanting to make sure that the secondary line was being fully flushed and apparently it is given that the bleeder on the lspv is dedicated to it.

 

[LandCruiserPhil]

Vacuum pump for the win

 

[jpoole]

Phil, is there much difference with vacuum vs pressure? I've yet to try a vac. system, which do you use/prefer?

 

[LandCruiserPhil]

Phil, is there much difference with vacuum vs pressure? I've yet to try a vac. system, which do you use/prefer?

I have both but prefer the vac. Not a fan of brake fluid and pressure because brake fluid and paint is not a good combo in the event of failure.

I like to keep it simple
Amazon product ASIN B013VUZ7WG

 

[cvenom96]

Key to mine was hotwiring the ABS according to a diagram I found on here. Cycling it multiple times resulted in lots of dark fluid and bubbles even after I had bleed many times and probably put 3 bottles of fluid through the thing. Finally stops awesome again.

 

[jpoole]

Is the approach you used in the following thread @cvenom96 ?

Is there a way to trigger ABS actuator to combat spongy breakes?

Truck info: 1994 LC with ABS So after some brake work (Caliper replacement with pads) I had spongy brakes. Wasted good amount of brake fluid trying to bleed them. I suspected that Air was trapped in ABS actuator but short of buying the SST tool or driving on Ice I did not see a way to trigger...

forum.ih8mud.com

 

[cvenom96]

Is the approach you used in the following thread @cvenom96 ?

Is there a way to trigger ABS actuator to combat spongy breakes?

Truck info: 1994 LC with ABS So after some brake work (Caliper replacement with pads) I had spongy brakes. Wasted good amount of brake fluid trying to bleed them. I suspected that Air was trapped in ABS actuator but short of buying the SST tool or driving on Ice I did not see a way to trigger...

forum.ih8mud.com

Yep post 35

 

[flintknapper]

Two people working for 5 hours means you would have payed yourself $5/hour. Sometimes it really is better to bite the bullet and buy a tool that will make a job so much easier and faster. Glad you got it figured out.

Amazon product ASIN B0002KM5L0

 

[sunrk]

My motive products power bleeder is my go-to. Sadly the only way to use it with an 80 series is with their 'universal' fit cap that's a bit finicky to get a good seal with (it's j-bolted with a small chain around the master cylinder to make it seal) but the product works. I use it with the 80, and with my cars. If Toyota made it's brake and clutch master cyls with screw on instead of clip-on lids there would probably be a better solution.

Has anyone tried that Power Probe BA10 device pictured above connected to a MP power bleeder by any chance? I refuse to buy anything from Amazon though.

The MP power bleeder uses a tapered thread connection for the end-piece with the adaptor so that's different to the Power Probe ones (btw the Power Probe website doesn't list the brake bleeding adaptor products or the full kit - are they NLM?) - what sort of fitting is on the Power Probe ones?

 

[flintknapper]

My motive products power bleeder is my go-to. Sadly the only way to use it with an 80 series is with their 'universal' fit cap that's a bit finicky to get a good seal with (it's j-bolted with a small chain around the master cylinder to make it seal) but the product works. I use it with the 80, and with my cars. If Toyota made it's brake and clutch master cyls with screw on instead of clip-on lids there would probably be a better solution.

Has anyone tried that Power Probe BA10 device pictured above connected to a MP power bleeder by any chance? I refuse to buy anything from Amazon though.

The MP power bleeder uses a tapered thread connection for the end-piece with the adaptor so that's different to the Power Probe ones (btw the Power Probe website doesn't list the brake bleeding adaptor products or the full kit - are they NLM?) - what sort of fitting is on the Power Probe ones?

I use my Motive with a BA10 cap on both my 80 series and 100 series. Works fine.

 

[ceylonfj40nut]

Do you know of a cap that would work on 40 series dual reservoir system?

 

[sunrk]

I use my Motive with a BA10 cap on both my 80 series and 100 series. Works fine.

View attachment 2862294

What is the quick connect coupling called? Like it's not Nitto, etc. It looks like something specific to the USA. But should be easy to get fittings for.

 

[robnicko]

all these tools etc, what about the good o'l clear tube and bottle?
I have always used this method for numerous vehicles and bikes abs & non abs and never had any issue - only prerequisite is having an assistant pump the pedal

The key is to always start bleeding furtherest away from the master cyl and work your way to the closest bleeder to the M-Cyl & never let the M-Cyl get too low

 

[ChaseTruck]

So, from the cheap seats...

I found it helpful to tap/rattle on the lines to the rear with a wrench, with the system under pressure - that tends to dislodge stubborn air bubbles.

 

[sunrk]

If you have a helper then yes it's easy to bleed via a non-pressurised reservoir method but you have to ensure the reservoir stays at least half full.

Another reason a power bleeder is good is that you can flush *all* the old degraded fluid out and ensure there's nothing left but new fluid. To do it even more properly you can take the calipers off and drain out the remnant of old fluid that bleeding might not remove, but I don't know anyone who does that.

 

[flintknapper]

What is the quick connect coupling called? Like it's not Nitto, etc. It looks like something specific to the USA. But should be easy to get fittings for.

Typical Air Hose 'Coupler'.

I use it since it makes attaching the BA10 adapter to the fluid reservoir easier (not fighting the hose) AND I made an extension hose that allows me to place the Motive Pump on the ground or a table away from the vehicle if I desire. So...I first install the BA10, make sure it is seated well...then attach the hose. I can also extend the line if I need/want to.

These things aren't 'necessary' just makes it more convenient to use.

 

[sunrk]

The fitting that attaches to the male quick-connect on the BA10 - is that something like a Milton 716 fitting? It looks a bit like a Jamec fitting but not sure if it's identical. I can tell it's definitely not Nitto-style.

 

[flintknapper]

The fitting that attaches to the male quick-connect on the BA10 - is that something like a Milton 716 fitting? It looks a bit like a Jamec fitting but not sure if it's identical. I can tell it's definitely not Nitto-style.

Use a 'universal' coupler. It will accommodate the three most common types.