I have an 84 fj60 about 2 weeks ago my red brake light started flickering and the pedal went to the floor no leaking anywhere Reservoir remained full but I had no brakes I replace the master cylinder bench bled it first after I got it installed bled the entire system now seems like I Have partial breaks it doesn't go to the floor but I have to use quite a bit of pressure to get the truck to stop the brakes just do not feel the same any help would be appreciated
brake issues (1 Viewer)
- Thread starter Epax
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Skreddy
SILVER Star
Did you adjust the booster to master pushrod length when you installed the new master?
4runner2FJ60
SILVER Star
Brake booster? I had a similar experience, booster was toast also.
Both of these things need to be looked at.
I would also look through different threads on here in search for a possible booster upgrade to an 80 series booster. They are a bolt in and will make a difference as well in the end.
Doesn’t hurt to directly bleed the proportioning valve - but I’m not sure if the ‘84 model year even had a proportioning valve.
- Thread starter
- #6
no I didn't adjust the push rod wasn't aware I needed to do that any ideas and I'm also hearing a hissing sound when I press the pedal sounds like it's coming from inside the vehicle almost or right at the firewall
Skreddy
SILVER Star
Hiss would lead me to check for a vacuum leak at the booster in the seal where the pedal pushrod goes through.
- Thread starter
- #8
looks like I've got some work to do brake booster brands and where to get one just in case. AISIS?
- Thread starter
- #10
I meant Aisin, good reviews But can't find an Aisin Booster for sale any ideas
Sometimes when a master cylinder goes bad it leaks fluid into the booster and ruins it too.
The 60's booster is weak compared to the 62's. '95 4 Runner booster is the same size as the 62's and the 80's and usually available at your LAPS (probably Cardone brand). The mod will require an external check valve (the 62's is steel and is exceptional) and, because it is slightly thinner, you will need to bend the brake lines a few degrees. Bench bleeding the master and checking the booster pin/master piston relation is essential.
The 60's booster is weak compared to the 62's. '95 4 Runner booster is the same size as the 62's and the 80's and usually available at your LAPS (probably Cardone brand). The mod will require an external check valve (the 62's is steel and is exceptional) and, because it is slightly thinner, you will need to bend the brake lines a few degrees. Bench bleeding the master and checking the booster pin/master piston relation is essential.
I was thinking the same. On my old 4runner my booster was having problems and when i took it off i could feel brake fluid in the booster itself. Do you have any more info on the check valve? Im actually about to put an early 80 series booster and MC into mine
- Thread starter
- #13
can you explain the booster pin Master piston relation a little bit more do I need to make an adjustment first time doing this
g-man
SILVER Star
- Thread starter
- #15
awesome thank you very much!!!
g-man
SILVER Star
no need to disconnect the master cylinder brake lines. They can flex and you can pull it forward enough to wiggle the booster out. If you disconnect them you will be busy bleeding the master cylinder.
An 80 booster is an upgrade but the 80's master isn't (unless you're also changing calipers).
Here's an excerpt from a thread installing the check valve:
Frankie - '87 FJ-60 Refurbishment Plus a Few Mods
Keep at it man. Looks great. You always get your highs and lows of enthusiasm, but stay the course. You'll be happy in the end. Even if it sits in the garage most of the time. :hillbilly:
forum.ih8mud.com
See post #218
The master was leaking and I replaced it with a new Advics with days of soft pedal and bleeding problems. This prompted the replacement of the booster with a 4-Runner unit. After changing multiple masters and boosters, both new and used from a known good FJ-62, and bleeding nearly a gallon of brake fluid, I gave up and parked the truck out of frustration. A month later I decided to tackle the problem again, started the engine, tested the brakes and they worked perfectly. My best guess for what happened is that an air pocket remained in the master and gradually cleared itself over the month of sitting. I'll take the win but it wasn't my work that solved the problem.
the FJ-62 and 4-Runner's don't have an internal check valve like the 60's so one needs to be added when making the swap.
The short version about braking and brake upgrades is this:
The 4-Runner caliper swap is not worth it. It doesn't improve heat absorbing capacity and properly functioning stock calipers are capable of locking up the tires. It's not possible to get more braking than locked. I don't recommend the swap.
Many people also change the master. This too is not necessary. The OEM master feels just fine with the 4-Runner calipers. A bigger bore gives a harder pedal feel but actually reduces the pressure received by the caliper. I don't recommend the swap.
FJ-62/4-Runner booster is the key to getting better braking. The additional boost provides a remarkable difference in effort and feel at the pedal. I removed a working OEM 60 booster and replaced it with a cheapo A-1 Cardone and will not go back unless I sell the truck and someone insists on returning completely to OEM. I highly recommend this swap.
If you want really strong, modern brakes you have to address the tiny, thin disks. FROR sells a Tundra mod. I just installed one on my HJ and, so far, like it. I'll try to start a build thread on Ishmael in the next couple of weeks with part numbers and pictures. It's been done many times but I haven't seen a recent thread with details.
An 80 booster is an upgrade but the 80's master isn't (unless you're also changing calipers).
Here's an excerpt from a thread installing the check valve:
Frankie - '87 FJ-60 Refurbishment Plus a Few Mods
Keep at it man. Looks great. You always get your highs and lows of enthusiasm, but stay the course. You'll be happy in the end. Even if it sits in the garage most of the time. :hillbilly:
See post #218
The master was leaking and I replaced it with a new Advics with days of soft pedal and bleeding problems. This prompted the replacement of the booster with a 4-Runner unit. After changing multiple masters and boosters, both new and used from a known good FJ-62, and bleeding nearly a gallon of brake fluid, I gave up and parked the truck out of frustration. A month later I decided to tackle the problem again, started the engine, tested the brakes and they worked perfectly. My best guess for what happened is that an air pocket remained in the master and gradually cleared itself over the month of sitting. I'll take the win but it wasn't my work that solved the problem.
the FJ-62 and 4-Runner's don't have an internal check valve like the 60's so one needs to be added when making the swap.
The short version about braking and brake upgrades is this:
The 4-Runner caliper swap is not worth it. It doesn't improve heat absorbing capacity and properly functioning stock calipers are capable of locking up the tires. It's not possible to get more braking than locked. I don't recommend the swap.
Many people also change the master. This too is not necessary. The OEM master feels just fine with the 4-Runner calipers. A bigger bore gives a harder pedal feel but actually reduces the pressure received by the caliper. I don't recommend the swap.
FJ-62/4-Runner booster is the key to getting better braking. The additional boost provides a remarkable difference in effort and feel at the pedal. I removed a working OEM 60 booster and replaced it with a cheapo A-1 Cardone and will not go back unless I sell the truck and someone insists on returning completely to OEM. I highly recommend this swap.
If you want really strong, modern brakes you have to address the tiny, thin disks. FROR sells a Tundra mod. I just installed one on my HJ and, so far, like it. I'll try to start a build thread on Ishmael in the next couple of weeks with part numbers and pictures. It's been done many times but I haven't seen a recent thread with details.
Ahh okay thank you for the link, i did not think about the check valve. I have a known good booster from an early nonabs 80 series and was going to buy a new non abs 80 series MC.
These are going to be used on my 60 with late 80 series axles and calipers. I believe the calipers and MC bore size was the same, just the later ones had abs and the earlier ones didnt. I totally agree though, the MC upgrade isnt really an upgrade if you are keeping the 60 calipers
FJ62 check valve if adding a booster lacking an internal valve.
