71 hilux brake bleeding troubleshoot

Discussion in 'Maintenance/Repair' started by 71hans, Aug 2, 2011.

  1. 71hans

    71hans Member

    Joined:
    Jul 17, 2011
    Messages:
    49
    Likes Received:
    0
    Location:
    Nebraska
    Truck:
    71 Toyota Hilux
    I am working on bleeding my brake lines on a 71 hilux. When I pump the brake pedal I get pressure but then the pedal sinks back down to the floor and have to re-pump to get pressure. I replaced the master cylinder and checked the lines for leaks but have found none. Is this normal on these older trucks? Also, I can't get the back wheel brakes to bleed even after replacing the master. Any suggestions on this? What methods do guys use to bleed the brakes on these trucks. I would rather not buy a bleeder.
     
  2. StupidSheet

    StupidSheet Addict

    Joined:
    May 17, 2008
    Messages:
    774
    Likes Received:
    1
    Location:
    Canada
    Truck:
    91 V6 SR5 Xtracab, 87 22RE 4x4, 73 HiLux 18R SR5
    Did you bench bleed the master? Sounds to me like you still have air in the lines or maybe a plugged line. What condition are the lines in? Should some need to be replaced?
     
  3. 71hans

    71hans Member

    Joined:
    Jul 17, 2011
    Messages:
    49
    Likes Received:
    0
    Location:
    Nebraska
    Truck:
    71 Toyota Hilux
    I did bench bleed the mc. As far as I can tell, the lines are good. There is no leaks anywhere. The only issue that I did find was that I was unable to disconnect the brake lines from the rear wheels due to the tightening nut and the brake line being rusted or fused together so when the nut was turned the line would also turn. I did not want to create a bigger mess and decided to leave them. The only reason for disconnecting the lines was to blow the lines out with an air compressor. What is your method of bleeding? There seem to be many theories out there. have you bled the lines by your self before?
     
  4. dillinja666

    dillinja666 Toyotaholic

    Joined:
    Feb 19, 2010
    Messages:
    2,115
    Likes Received:
    2
    Location:
    san diego
    Truck:
    I gots no truck, for now
    well to bleed by yourself you need a vacuum bleeder. If you got a friend have him pump the pedal while you open and close the bleed screws one at a time. you know, have him hold the pedal down open the bleeder and then close it, then have him pump it a few times and hold it to the floor again, repeat repeat repeat a bunch of times on each bleeder until the pedal feels normal.
     
  5. StupidSheet

    StupidSheet Addict

    Joined:
    May 17, 2008
    Messages:
    774
    Likes Received:
    1
    Location:
    Canada
    Truck:
    91 V6 SR5 Xtracab, 87 22RE 4x4, 73 HiLux 18R SR5
    Ya just like dillin says if you have someone helping you. I bought a vacuum bleeder so I can do it myslef. Well worth the cash IMO. When you bleed, start with the one that is furthest from the MC and then next furthest and so on. Usually passenger rear but not always. In the meantime make sure the MC does not go dry. Hope this helps and keep us posted.
     
  6. 71hilux

    71hilux Member

    Joined:
    May 13, 2010
    Messages:
    37
    Likes Received:
    0
    Location:
    Southern Oregon
    Truck:
    71 Electric Hilux 4 speed
    Did you ever find the problem? I am having a similar problem with my 71 Hilux. My brakes would only work after pumping about 5 times. I also replaced the master cylinder so now it only takes two pumps. I have bled everything multiple times and adjusted all the brakes but the brakes still don't work til the second pump. Any ideas? Thank you.
     
  7. 71hans

    71hans Member

    Joined:
    Jul 17, 2011
    Messages:
    49
    Likes Received:
    0
    Location:
    Nebraska
    Truck:
    71 Toyota Hilux
    Hey 71hilux,

    ya we figured out that the rear brake line was plugged, so we replaced it. After the new brake line was on we figured out that the brake cylinders were all shot...so we replaced them. I had a friend mechanic adjust them and bleed the lines for me. He said he had the same problem with no brake on the first pump but on the second. He told me he adjusted the brakes to the max, barely rubbing the drums. As of now I do have a little brake on the first pump but if I want good brakes I need to pump them twice. He thought maybe the stock master cylinders were did not have the capacity they should to give enough hydraulic for the brakes on one pump. I have learned to live with it for now. I wonder if the vac booster needs to be adjusted to give more force on the first pump? I'll check my books again and see if I find something. Let me know if you have any luck with it.
     
  8. 71hilux

    71hilux Member

    Joined:
    May 13, 2010
    Messages:
    37
    Likes Received:
    0
    Location:
    Southern Oregon
    Truck:
    71 Electric Hilux 4 speed
    Thankyou for the reply. It helps knowing other trucks have the same problem. I think the problem is a combination of having two cylinders on each front wheel and also the drums being out of round so I can't adjust the shoes tight enough to take up the slack without them dragging on the high spots if you follow me. I did find a fix though. The manual says to make sure there is certain amount of free play in the pedal which I think is to allow some of the fluid to bleed off. In my case I think it is better to eliminate the free play. I loosened the lock nut on the brake pedal rod and turned it in the direction that effectively lengthened it until after pumping it the first time it didn't let the fluid bleed off all the way. The Hilux still moves easily when I let off the pedal but I no longer have to pump it twice which has to be much safer. I'll let you know if I have any more trouble but so far so good.
     
  9. RningOnFumes

    RningOnFumes Newbie

    Joined:
    Mar 26, 2011
    Messages:
    15
    Likes Received:
    0
    Location:
    San Bernardino, CA >>>>> SoCal
    Truck:
    1972 Hilux 4spd
    I have pretty much the same problem. I'm at the stage where I need to replace the master cylinder. I have a '72 Hilux and am having trouble sourcing the part new. What did you use and to everyone else, is there a later model year I can substitute for? Lastly if there are substitutes are there any differences in performance or are they all the same?
     
  10. 71hans

    71hans Member

    Joined:
    Jul 17, 2011
    Messages:
    49
    Likes Received:
    0
    Location:
    Nebraska
    Truck:
    71 Toyota Hilux
    RningOnFumes,

    I went to my local parts store, which I think is Car Quest and they were able to get me a master cylinder. I tried Napa first but they didn't have anything and I also looked on ebay but didn't find anything but I would check it again. I think it works good, I still have to pump the brake peddle twice before I get really good braking, I'm not sure why and neither did my mechanic.
     
  11. 71hans

    71hans Member

    Joined:
    Jul 17, 2011
    Messages:
    49
    Likes Received:
    0
    Location:
    Nebraska
    Truck:
    71 Toyota Hilux
    71hilux,

    Good to know, I'll check that out and try adjusting the pedal. The mechanic who put the brakes on for me also had problems taking the slack out without them dragging on the high spots....must be a common problem. Have you done any work on your carb? Mine is starting to give me more problems. I am debating between replacing and rebuilding.
     

Share This Page