My 1968 F600 has no brakes. Gas engine. Just one fact before we start, Front wheels have no bleeder fittings, previous owner sealed them, so I plan to replace front cylinders when I can get it home.

I started by filling the master cylinder and tried to get bleed the back brakes and frame mounted booster. After replacing multiple rusted and leaking lines, getting good flow to the back brakes and the booster,, still NO brakes.

Replaced the master cylinder and the booster, still no brakes.

SO what should I try next,,, I just really want to get the brakes working well enough to get the truck home safely. 10 mile low speed trip.

 

What a freaking dipstick. I am thinking there is still enough air at the front to keep it from working.

You might go out on a Sunday morning with a couple tires on the rear bumper of another truck and play bumper trucks (Very Carefully) until you got it home. Or place a tow strap on the rear and use the second vehicle for brakes.

Go slow at a very low traffic use time and you might be able to pull it off.



John

 

What wizardry is this? Why would anybody do that.

 

The same guy that designed the new clutch slave cyl. with no bleeders !

 

You might be able to bleed the fronts fairly well by cracking open the brake line where it screws into the wheel cylinder. That might at least get enough air out to get them working a bit.

Did you bench-bleed the Master before you installed it? I always wind up cracking the lines open where they attach to the Master to bleed a little air out after installing. Helps to get the Master to pump up a lot quicker. I just pump the pedal and even if it's not getting firm I hold it down and crack the lines, usually get a small puff of air and then fluid. After a couple cycles it starts to firm up.

Did you bleed it at the booster too? I assume so, since you state you're getting good flow to it...

 

Have seen some stupid stuff, tho usually there was a method to the madness at least.

 

My respectful advice based on the issue

Rebuild the entire system.. starting with wheel cylinders and moving to brake master,, and then hydrovac.. brake hoses as well (good call on master and hydrovac)

Never compromise on old medium duty brakes at all.. especially when the PO did something wierd.. there is no reason to "seal" brake cylinders .. which means the monkey mechanics were at work.. that means someone didnt know what they were doing.. that means potential catostrophic failure