75 40 brake problems (1 Viewer)

[big daddy diesel]

Hey guys hope you can help me out here. Got my 40 delivered yesterday. on the way home I found out i had know brakes. When I pumped them i got a pedal and stoped fine. but if ijust depressed them goes rihgt to the floor. So today i replaced the master cylinder bleed the brakes. I nocticed that the rears had very little pressure.
and i still have the same problem. any help would be app

 

[Rice]

If having to pump them up it sounds very much like the shoes are too far from the drum and need adjusting. Long ago there was a super write-up by Jeff Zepp on how to make your brakes perfect (in the tech section).

Because you have a 75 the front brakes are disks, right? If so I would doubt the fronts are part of the issue.

Rice

ps ... oh, and welcome.

 

[big daddy diesel]

I will try and adjust them tommorow. It does not have disks in the front. production date july 75. If anyone has a link to this write up please post it. Did not see it in tech section. thanks

 

[HawkDriver]

Not much help, but I know what you're goin through. I adjusted and adjusted, bled and bled and never figured it out on my 73 with all 4 drums. I figured that it was air in the sys that I could never get out.

Yeah, check the adjustment and then bleed like crazy. Good luck.

 

[brownbear]

Maybe something like this would help the bleeding problemos

Kit, Brake Bleeder, Vacuum-Type, Basic

Stock#: BB200B
$256.95

But there must be a cheaper version. Pumping and bleeding is pain.

 

[mhdsummers]

Trace the brake line from the wheel cylinders to the master cylinder. Make sure there are no kinks or leaks. Dont skip this part. Do this for each wheel. If no leaks are found in the lines, replace the wheel cylinders. If the cylinders have never been replaced, you probably need new ones. I am assuming you are bleeding the brakes correctly. You probably have a leak somwhere if you replaced the master cylinder correctly and still do not have firm brakes.

Check Jeffs pages here:
http://rzeppa.org/

Brakes:
http://rzeppa.org/tech/brakes.htm

 

[gladly]

coolerman's site has a great writeup on bleeding drums,
http://www.globalsoftware-inc.com/coolerman/fj40/15C.htm
in fact there is a load of useful stuff there
http://www.globalsoftware-inc.com/coolerman/fj40/main.htm
it's my main reference for all the projects I mean to do.

 

[Pin_Head]

When I pumped them i got a pedal and stoped fine. but if ijust depressed them goes right to the floor.

This is a classic sign that they need adjustment and not bleeding. If the pedal height increases when you pump the pedal, they need adjusting. If the pedal is firm, then they don't need bleeding. If the pedal is spongy, it might need bleeding too. There are two problems with adjusting them. The first is that the adjusters are often stuck. The other is that poeple don't adjust them tight enough because the dragging noise scares them. Tighten the adjuster until you can't turnt he wheel and then back of 2-3 clicks until you can just barely spin it one revolution.

 

[big daddy diesel]

Well adjusted the brakes today and i now have a pedal and some half ass brakes. When I was ajusting them I noticed that they really need to be turned,
rubing on one side and not the other. So rather then deal with drums i would like to switch to disc. So can anyone recomend a good bolt on kit. I do not want to have to fab anything just bolt on. Thanks for the replies and links they helped a lot

 

[gladly]

complete axle/diff off a newer 40 with discs, apparently it doesn't get much easier, remove old, install new, might have to remove and toss away a little regulating washer from the brakeline at the MC
so i'm told, haven't gotten around to installing mine yet.
and cheap too, I got the whole works for $120 and it's got reasonable pads and rotors in it.

 

[Rice]

Well adjusted the brakes today and i now have a pedal and some half ass brakes. When I was ajusting them I noticed that they really need to be turned,
rubing on one side and not the other. So rather then deal with drums i would like to switch to disc. So can anyone recomend a good bolt on kit. I do not want to have to fab anything just bolt on. Thanks for the replies and links they helped a lot

There are several options for installing disks. I suggest using the search function to find some details. All the options have been discussed here multiple times.

On the other side, it does not sound as if your brakes are in that bad of shape and when properly adjusted drum brakes do have strong stopping power.

 

[unstable_geek]

I second Pin_head's comments, I have 4 whell drums, and I know that my drums are too worn and need replacing. I also know that my wheel cylinders are pretty shot too - since I have to take the drum off to adjust them.

The symptoms to describe are exactly the same as what I have - I have to pump the brakes a few times to get them to engage, but they will stop the truck. Tad scary though!

I would take the drums off, and check them with a micrometer for the tolerance (I dont what that is off hand), replace them if needed.

I'm lucky, plenty of guys I know have replaced there drums with discs, so its just a metter of sorting through the pile of old drums to find some in tolerance.