FZJ80 brake bleeding hell

[Brian894x4]

The brakes on my '95 FZJ80 were a tad mushy, so I thought I'd bleed and see what happens....

I spent half the day yesterday and half the day today bleeding...and bleeding...and bleeding. I've got the clearest and cleanest brake fluid I've ever seen, but not only do I still have mushy brakes, now I have brakes that go almost (although not quite) to the floor, when the engine is turned on. With the engine off, the pedal feels OK, although when I really stand it, it's pretty low. I'm pretty sure it's not drivable at this point. However, it was perfectly drivable before I started messing with bleeding the darn things.

I've followed the FSM to the letter again, and again. Even did the master cylinder several times. At this point, I'm wondering if my master cylinder was going bad and bleeding the brakes just caused it to go over the edge somehow or if I just need to keep bleeding, because I still have air in the system.

I'd certainly appreciate any insight as to why it is so difficult to get air out of the system, compared to other rigs, assuming that's my problem. I thought maybe the ABS was trapping air, but I've read this problem is occures on the FJ80s too. My other theory is that some how the return line from the LSVP is trapping air and not letting it out.

The FSM says to "bleed the by-pass pipe", but makes no mention of what exactly that is. I'm guessing they are referring to the LSVP, which I've definately bleed over and over again. But I would sure love to know if they mean something else and I'm missing something.

[Boston Mangler]

Hey Brian

I also had a very hard time bleeding the brakes on my 80, for some reason, it took A LOT longer then most rigs to get it dialed in. Weird, i have read the FSM several times and dont recall any mention of a "bypass pipe" maybe thats my problem! :D

Sounds like you have done all of the usual stuff.

I will bet my $ on the MC, although you VERY rarely hear of those going out on these trucks. If all else fails, i suggest "Bench" bleeding the Master Cylinder and trying the whole process over again before you go out and buy a new one.

I ended up going with the one person speed bleeders from Napa and they work great! The first time i bled my brakes, some really gnarly crap/goo came out of those lines.

My .02

[Grim Reaper]

Is it on jack stands with the rear wheel dangling? The LSPV will make it feel like doo doo sometimes. The rear brakes are the majority of brake feel. Put it at ride height and see how it feels.
Got a vacuum pump? Pull a vacuum on the master reservoir for a couple hours.

[Mlachica]

Oh man, I hope you're able to figure it out. I saw the nipple at the LSPV but only used the four corners to bleed.

I didn't refer to the fsm, I just had somebody at the peddle and pumped it until clear fluid came out (while keeping reservoir full). Once I felt it was good enough, he depressed the peddle until I closed the nipple. And did this at every corner.

Just make sure you tell him to let off the pedal before you loosen the next valve, or you might get shot in the face - like somebody I know :oops:

[Brian894x4]

Well, I have the axle on jack stands so the LSVP is sitting normally. I'm going to try something different tonight, based on some stuff I saw on Mud.

I'll bleed using the pedal method with the engine on. I have a feeling this might be the little known trick to fix the LC80 bleeding problem, but we'll see.

I'll post results when I'm done.

[asteffes]

Here's the procedure I always follow on every car/truck I work on. It requires a helper and is the best way I know of to bleed brakes.

Helper gets in the car, turns key on, and maintains pressure on the brake pedal until told otherwise.

You take position at one corner of the vehicle with wrench for bleed screw.

Open bleed screw for two seconds.

Close bleed screw.

Tell helper "cycle," as in raise the brake pedal and again maintain pressure.

Open bleed screw for two seconds.

Close bleed screw.

Cycle.

Repeat 5-6 times. Check fluid level.

Tap caliper with rubber mallet to dislodge any air bubbles.

Bleed again, as needed, until no more air or debris comes out.

Move to next corner.


This method works well because there's no guesswork as to when to stop pushing the pedal. Your helper just maintains pressure until you say "cycle." You are certain to open and close the bleed screw while the fluid is under pressure, giving no chance for air to enter the system.

Hope this works for you.

[Brian894x4]

Thanks for the tips. Good info.

I'm a step closer, but still no dice.

I finally got a nice steady stream of fluid come from each corner with no bubbles, but the LSVP is still giving me headaches. Still got bubbles and pedal still goes to the floor.

I ran out of brake fluid, so I'll have to continue tomorrow. I used 3.5 full size cans today and total about 7-8 cans of brake fluid to get to this point. But now that I know what it looks when there are no bubbles, I at least know what to shoot for with the LSPV. I'm a little confused why I have no bubbles at the rear brakes, but still have air at the LSVP. I"m guessing it's the return pipe from the LSVP that still has air in it. I also wonder if that darn air in the return pipe and the fact that most people and brake shops don't bother bleeding the LSPV, much less use 8 cans of brake fluid, if all these complaints I hear about the 80s braking system might be nothing more than an improperly bleed brake system with air still trapped in the LSPV and return pipe.

By the time this is done, it's going to one seriously flushed system. I did test the master cylinder using the method where you put steady pressure on the pedal and see if it drops over time. It doesn't, so while the brake pedal does go to the floor with full pressure and the engine turned on, I'm think it's still just air in the system.

I also went to change the oil today and it took me about an hour to get the oil filter off, thanks to who ever the PO had change the oil over tightening it. Not a good weekend. But, I figured out if you just unbolt the power steering resevor, getting to the oil filter is super easy, assuming it's not overtightened.

[HongerVenture]

One other item that may come in handy...
http://www.motiveproducts.com/images/Import_Power_Bleeder_Small.JPG

It is the Motive Products Power Bleeder. (http://www.motiveproducts.com/) I picked one up used (only used once) off of Yotatech and absolutely love it. It makes bleeding the brakes a cinch. My wife doesn't have to pump the brake pedal and the system is under constant pressure. BTW, I don't have any interest in them, it has just REALLY made the job easier.

One other detail... when bleeding brakes by pumping the pedal you can cause the brake piston to travel further in the cylinder than it normally does. If there is corrosion or debris in that area, it can damage the seal on the piston. While this is typically a problem only in older vehicles or those with a poorly maintained brake system, it is a consideration. Was your fluid extremely discolored before you started?

Brian, are you bleeding the LSPV last, after all four wheels? I know for my truck the LSPV has to be bled last. Since you have the FSM, I'm sure you are but just thought I'd ask to be sure.

Hope you get it worked out.

[Brian894x4]

I've heard that product mentioned a few times with good comments. If all else fails, I may try to find one. I'll definately consider one if I have to do this again.

The FSM is very vauge about the brake system on a number of different points. They only mention start at the cylinder with the longest line first and that's it. Then the second sentence says, bleed the brake return pipe, but doesn't indicate what that is.

I assume that's the LSPV. It definately doesn't mention bleeding the LSVP by the name we all know it as, or in what order. However, since the LSVP feeds the back brakes, I assumed RR, LR then LSPV, then front. However, I've been doing it so much that I've gone out of order a number of times.

Now that all four wheels bleed good, but not the LSVP I'm kind of confused, except that I think the air coming out of the LSVP nipple is actually from the return pipe between the LSPV and ABS. If that's the case, then it might make sense that the LSPV needs to be done last.

As for the color, it was pretty good. I don't "think" I've damaged the master cylinder, but I'm heard of that being possible. I know I still have air in the LSVP line as I can see bubbles when I bleed.

We'll see.......

[Grim Reaper]

The line at the LSPV is a feed back line from the front circuit.

It works against a diaphragm in the LSPV. No fluid exchanges. The brakes should bleed in the same order as your 89. Four wheels then LSPV

[Brian894x4]

3.5 more full size cans and about 4 hours of my life I'll never get back and I still haven't fixed the problem.

I think I've used about 12 cans so far over the last 4 days. Or about 3 gallons of brake fluid to flush this POS out.

I have good solid fluid from all four wheel cylinders, and I finally have pretty good solid fluid coming from the LSPV, but I still get an occasional bubble, so I still have air related to the LSPV. The big problem is the brake pedal still goes almost to the floor when the engine is on. When it's off, it feels nice and firm, much better than even before I started bleeding. So, I can't figure that out. I guess I still have significant air in the system...somewhere.

I've done the master cylinder leak down test and when I hold firm pressure on the pedal, it does not move, so I don't suspect the Master Cylinder is bad.

At this point, I'm debating whether I want to keep bleeding the LSPV or just drop the darn thing off at the dealer and let them bleed it. I may try to find one of those before mentioned Power bleeders here locally. I'm in no mood to order something and wait for it. I just want to be done with this.

[Grim Reaper]

Have you drove it yet?

It might put you through the windsheild. Might have a very light peddle.

[kcowyo]

.....this POS

:xxrotflma

I'm not laughing with you, I'm laughing at you. Hang in there Brian!

[DaveInDenver]

It is the Motive Products Power Bleeder. (http://www.motiveproducts.com/) I picked one up used (only used once) off of Yotatech and absolutely love it. It makes bleeding the brakes a cinch. My wife doesn't have to pump the brake pedal and the system is under constant pressure. BTW, I don't have any interest in them, it has just REALLY made the job easier.

I have one of those Power Bleeders. It works well, I've used it for both brakes and clutch on my truck and our Civic. The only issue I've had so far is getting the cap on the clutch master takes some fiddling. Once you get it attached and sealed, works really well. I've heard some people speak negatively about it because the brake fluid and pressurized air are not separated by a membrane. This is common on pro bleeders that use shop air and apparently it's possible in theory to cause air to dissolve into the brake fluid, which then introduces air into your brakes. I dunno, I don't seem to have an issue like that. Anyway, this makes brake bleeding truly a one man job.

[Brian894x4]

Have you drove it yet?

It might put you through the windsheild. Might have a very light peddle.

You make a good point. I might be over reacting. I'm going to bleed it a little bit longer, since I was making progress and then test drive it. It might be fine after all. For some reason I assumed that the brake pedal shouldn't go down that far, but in driving other cars, it does.

[Boston Mangler]

Hey Brian

Just curious, how new is this vehicle to you?

I have driven quite a few 80's and all have a somewhat mushy feel.

Curious if this is an all of a sudden thing or if the rig is new to you and you think they are squishy comparing them to another rig.

Wondering if you are in search of the un-obtainable solid 80 pedal! :D

[Brian894x4]

It's brand new to me....I bought it in Feburary and I'm learning exactly what you said...that the mushy pedal appears to be very common.

However, I've read that it wasn't so when they were brand new, which makes me wonder if all these mushy pedals might just be brake systems that were not bled all the way. Someone correct me if that's not the case.

For example, last night, on the LSPV, Once I thought I finally got all the air out, I go a couple of squirts with no air at all and then all of a sudden air come out. Could it be, that people just stop bleeding as soon they see no more air, while air is still in the system and that's why the mushy pedal? I wonder if air just gets trapped somewhere in the system is just very hard to get out?

As far as my pedal it feels much softer than it did when I first started with the engine on, but I won't know for sure until I actually get it out on the road and test it that way. I do know that it feels much stiffer than before with the engine off...go figure.

[Boston Mangler]

I will follow this thread closely for the results.

I would be very happy to get a nice firm pedal on my 80 as well!

Let us know what happens!

Good luck!

[Life_in_4Lo]

The brakes on mine are good and no mushy feel. I've bleed them and went longest to shortest, engine off, pump pedal (but not all the way to the floor), kept resivoir topped (just turn a bottle upside down in the resiv). It went easy.

I also put in Slee stainless lines and have the extra to convert all the rubber lines to ss, so I will do that at some point.

[Brian894x4]

Update:

Bleed another 3 quart bottles today. Almost all of it through the LSPV. I checked the other wheels again and they're fine. I was getting a pretty regular stream of air bubbles. Started thinking, maybe they were coming in from somewhere else, but after a few hours, I could go a number of squirts without seeing any, then only very tiny ones now and then...then I ran out of fluid to bleed with, so I had to quit.

Decided to button it all up and test drive. Pedal is very mushy, very long travel and braking power sucks. It's hard to say if it's worse than it was when I started, but it's definately not better, which baffles me considering how much air I bleed out of there.

Did a few panic stops and it feels like it's trying to stop a vehicle twice it's weight. I also couldn't get the ABS to activate, although it was dry pavement.

Next plan of action is to check the pedal adjustment. If that doesn't work, I'll probably drop it off at a dealer and see what they say.

What does an LSVP do when they go bad? I'm wondering how the vehicle would react in braking and if maybe that's part of the problem. Otherwise, I suspect there's still air in the system somewhere. The fact is, I literally bled gallons of brake fluid through that system and was still getting air bubbles, so either something is wrong or Land Cruisers inherantly have a problem of bubbles staying hidden in the system somewhere.

[njtaco]

The brakes on mine are good and no mushy feel. I've bleed them and went longest to shortest, engine off, pump pedal (but not all the way to the floor), kept resivoir topped (just turn a bottle upside down in the resiv).

A bit off topic, but I've been working on vehicles for 20 years, in a variety of shops, including dealers, and never saw this done. A great tip...I'll be trying this soon! (60K service)

[Boston Mangler]

In all my time owner, wrenching and messing with 80's i have never heard of a LSPV going bad.

I am thinking maybe its the master cylinder, but also, dont ever recall one of those being bad either.

I dont know, sorry i cant offer more advice. 80's brakes are notoriously bad even when perfect, maybe you have it as good as you can get it.

Try driving a few other 80's to compare?

[Life_in_4Lo]

maybe thru the various methods, you somehow damaged the MC? Or the MC was on the way out and the vacuum machine damaged it?

I think maybe call C-Dan and see what he says, and buy a MC from him if needed.

My brakes engage quickly and predictably, no mushy-ness, firm at hard stops, etc. just normal, good brakes.

njtaco,
It's a trick I learned from a guru that has helped me. He is a Lexus Master Tech- neat trick that makes bleeding easy.

Also, another tip is to replace the bleeder screws with speedbleeders. it makes it a 1 man job and no risk of air bubbles.

[Brian894x4]

The dealer will do a powerflush for me tomorrow. We'll see how that goes. I've talked to folks over on Mud with the exact same problem and and a powerflush finally solved it.

I've done the leak down pedal test on the master cylinder so I don't think that's the problem, but obviously, if the dealer flushes it all out and it still has problems, then there aren't too many other options left except a bad MS.

I know LCs have problems, but the way it acts now is definately not stock.

If you read road tests when they were brand new, the LC80s stopped 60-0 in 150 feet. The same distance as the 100, so the original brakes were pretty good. I think most LC80 brake issues have to do with air that's left in the system, because they are so hard to bleed out the air, but we'll see.

[Mlachica]

Good luck, I hope this solves your problem.

I was intending to flush my brakes again just to be sure I get all the muck out, but after reading this I think I'll let it be for a while.

Let us know...

[Brian894x4]

Update:

The dealer power flushed it for me and that apparently did not solve the problem. They then said that they thought the master cylinder to power booster connection needed adjustment, so they removed the MS and adjusted the connection. That actually did make a significant improvement.

The pedal is firmer down low and braking is definately improved, but the travel is still longer than I'm normally used to in other vehicles. The mechanic theorized that it could be the aftermarket front calipers that the PO installed as they appear to use more fluid than normal. He also said it could be the high number of brake hose in the design which allows it to flex. I've heard this over on mud too.

I'm going to try one last thing and check the pedal adjustment. Beyond that, I think it's probably as good as it's going to get, which is at least significantly better than it was. I might someday upgrade to steel braided hoses and try OEM calipers, but after all that bleeding, I'm no mood to open up the brake system anytime soon.

Now, I'm off to mess with my electrical system install my new duel batteries.....