- Thread starter
- #21
Awesome. This is great. May have to run my shopping list by the group to make sure I am not forgetting anything. The wheel cylinder's were replaced 2 years ago so they are in decent shape.
78 FJ40 mushy brakes
- Thread starter Kmall
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Awesome. This is great. May have to run my shopping list by the group to make sure I am not forgetting anything. The wheel cylinder's were replaced 2 years ago so they are in decent shape.
- Thread starter
- #22
Ok. Going to get started here. I have a Racer Booster, new master cylinder, and new front calipers and pads.
I know this may sound like a stupid question, but would you do the calipers first or the master and booster? Or does it matter?
Any abnormal tools for this job? Any last minute tips?
Much thanks. I appreciate the help and will no doubt be back when I mess something up.
I know this may sound like a stupid question, but would you do the calipers first or the master and booster? Or does it matter?
Any abnormal tools for this job? Any last minute tips?
Much thanks. I appreciate the help and will no doubt be back when I mess something up.
It shouldn't matter which you do first. A teenage son would be helpful to lay under the dash and do that part.
With that being said, I would do booster and master first.make sure you bench bleed the master. Can do that on or off the car.just read about it new master should have bleed adapters included.
With that being said, I would do booster and master first.make sure you bench bleed the master. Can do that on or off the car.just read about it new master should have bleed adapters included.
- Thread starter
- #24
Ok I am officially at the stage of needing help. Replacement of all components seem to go off without much of a hitch. Replaced with @Racer65 booster, master cylinder, and front calipers. 2 problem I have run into. When adjusting the booster push rod, I know the clearance can be a bit of an issue. I had to back the adjustment nut as far back as it could go. Couldn't tell if after this it was still touching but it was close. 2nd - I have bled the brakes 3 times now and the pedal still goes to the floor. During bleeding process you could pump the pedal three times and it had solid resistance. Once it is running, the pedal goes to the floor. If you pump it it will hold for a second, then softens towards the floor. Any thoughts here? It is possible that the brake lines still have air in them but I would think this would be getting a little better as go. Doesn't seem to be the case. And preemptively, yes I bench bled the master. Help is definitely welcome.
Much thanks
Much thanks
What type of MC did you install? Can you show a pic or part #?
If pedal goes to the floor, one of the following could be the cause:
1) MC is the wrong type or has a problem (Thus the question above)
2) Booster rod (MC side) is adjusted too short, thus requiring a long travel to activate the MC
3) Air in the lines (less likely given what you've done)
If pedal goes to the floor, one of the following could be the cause:
1) MC is the wrong type or has a problem (Thus the question above)
2) Booster rod (MC side) is adjusted too short, thus requiring a long travel to activate the MC
3) Air in the lines (less likely given what you've done)
- Thread starter
- #26
The Master Cylinder is From Napa - M2284 - for what its worth, it bolted right up. I have attached a picture. Not sure how to tell if it is not right or not functioning.
Number 2 is certainly possible. If its this, any trick to getting this right?
Thanks,
The MC is the correct type from what I can tell. It's probably an aftermarket unit made by Dorman, which is fine.
On the booster rod adjustment, I recommend this video. It's somewhat lengthy but the information given is correct and applicable. For your purpose you can start at the 30 min mark.
On the booster rod adjustment, I recommend this video. It's somewhat lengthy but the information given is correct and applicable. For your purpose you can start at the 30 min mark.
- Thread starter
- #28
Much thanks. I will let you know how it goes. Can this be accomplished without disconnecting brake lines of master or do I need to start over again. Just need to get my mind right.
Yes. Haven't watched the video, but you can unbolt the master, adjust the pushrod, and reinstall to the master. The brake lines have plenty of flex.
- Thread starter
- #30
Just to give an update and more to highlight by inability to fix this problem. I followed the video Racer65 posted and adjusted the pushrod accordingly, with a caliper. Put it all back together - same problem. Pedal resists at first, then goes to the floor. I am sort of out of ideas at this point. I have bled brakes multiple times. From the gaps between these posts, you can see my time has been limited. Any other ideas would be appreciated...or conversely, if anyone is in the Maryland area that might be able to tackle it, I'd love to hear.
Thanks,
Thanks,
Did you readjust your rear drums? Adjust until it drags and then back off one click. Smash the brakes and then recheck.
- Thread starter
- #33
Ok, here is where I am at. I have adjusted the rear brakes as suggested. I removed the replacement booster from Racer65, just to see if I could help isolate the problem. I bled the brakes multiple times and actually swapped out the master cylinder thinking there may have been a blown seal in the new one. Bench bled the newest master and still have the same problem. When the vehicle is off, the pedal can be pumped and it seems to hold. When running the pedal will go to the floor. I am really out of ideas at this point. Either I am doing something wrong in this process and not getting all the air out, or something beyond my skill level is wrong with the brakes. I will take any final suggestions - If not, I need to find someone in the Baltimore area who would be able to figure this out. Thanks to everyone for past and future help!
Are you bleeding the brakes in the correct order? Rear pass, rear driver, front pass, front driver.
How are you, specifically, doing the bleeding process? Person in the driver's seat, pumping the pedal? Plastic line from bleeder going into a small jar of brake fluid? Some other way?
I know I've had a couple of bleeder fittings that leaked, even when tightened properly. Have you checked there?
How did you proceed with the bench bleeding of the master?
How are you, specifically, doing the bleeding process? Person in the driver's seat, pumping the pedal? Plastic line from bleeder going into a small jar of brake fluid? Some other way?
I know I've had a couple of bleeder fittings that leaked, even when tightened properly. Have you checked there?
How did you proceed with the bench bleeding of the master?
- Thread starter
- #35
Yes to bleeding them in the correct order.
For bench bleeding, I have used a bleeding kit whereby the two plastic fittings go in the top line ports - a bleeder hose go from each fitting into the reservoirs. System is filled with fluid and using a artificial plunger - I have been slowly pushing the piston and drawing it back out until I have no more bubbles in the reservoir.
As for the bleeding itself, I have been using the only real method that has worked for me, which is what you describe. small hose attached to the bleeder fitting into a jar of fluid. Assistant holds pedal down - bleeder opened - bleeder shut - pedal up - repeat. I recently tried the pumping version but did not seem to make a difference.
regarding your theory about the bleeder fittings - back seem to be fine, but the front calipers are new - with obviously new fittings. This thought had crossed my mind as with only slight turning - it seems they feel very loose. Both feel identical though so it would have to be a design defect I suppose. I am not sure how to check this other than replacing the fittings. (are these a standard size?).
In the past, with other vehicles, even when I don't get all the air out the first go round, the braking seems to improve. This just feels like there is no hydraulic pressure - but I can't seem to find any leaking anywhere.
For bench bleeding, I have used a bleeding kit whereby the two plastic fittings go in the top line ports - a bleeder hose go from each fitting into the reservoirs. System is filled with fluid and using a artificial plunger - I have been slowly pushing the piston and drawing it back out until I have no more bubbles in the reservoir.
As for the bleeding itself, I have been using the only real method that has worked for me, which is what you describe. small hose attached to the bleeder fitting into a jar of fluid. Assistant holds pedal down - bleeder opened - bleeder shut - pedal up - repeat. I recently tried the pumping version but did not seem to make a difference.
regarding your theory about the bleeder fittings - back seem to be fine, but the front calipers are new - with obviously new fittings. This thought had crossed my mind as with only slight turning - it seems they feel very loose. Both feel identical though so it would have to be a design defect I suppose. I am not sure how to check this other than replacing the fittings. (are these a standard size?).
In the past, with other vehicles, even when I don't get all the air out the first go round, the braking seems to improve. This just feels like there is no hydraulic pressure - but I can't seem to find any leaking anywhere.
JohnnyC
Long ago TLCA# 2231
To me it sounds like you still have air at the wheel cyls... it's a problem with cheapo non toyota cylinders
With the brakes apart and cylinders still on the truck remove the top of the cyl and fill with fluid at the wheel reinstall everything and adjust
You really need to have somebody pump it up ... when you are bleeding
With the brakes apart and cylinders still on the truck remove the top of the cyl and fill with fluid at the wheel reinstall everything and adjust
You really need to have somebody pump it up ... when you are bleeding
Make sure you are having someone pump the brakes until firm then open the bleeder. You will have to repeat this multiple times at each wheel. It doesn't take much air to screw things up. You may want to check the brake lines and fittings as well. Could be a leak there causing air Ito enter system.
Did you ever figure out the answer to your problem? I’m in the same situation and completely baffled.
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