1967 F100 Ranger Camper Special 2WD

I need to bleed the brakes because i put in a new M/C. Crawled under the truck and the line to the rear wheel cylinder has a 3/8 nut, but the bleeder screw is just a hair larger diameter, but too small for a 7/16 wrench. Is it a 10mm?

 

someone could have put a metric one in there or it could just be build up on it.

 

I've run into replacement wheel cylinders that had metric bleeders in them.

 

Yeah I'm sure they were replaced at some time before I bought the truck. I dont have my metric wrenches with me so I'll have to go get one in town. Thanks for the info.

 

"As original" .. no Ford truck came with any metric parts prior to 1980.

8M-2208 .. Bleeder Screw / 3/8" -24 x 1 11/64" long.

3/8" is the thread size, not the wrench size.

 

Thanks but it looks like the front bleeders are metric too. Bought a set of Craftsman metric wrenches, only goes down to 8mm and that wasn't small enough for the front. It was between 3/8 and 1/4. Didn't realize that my truck was part asian.

 

More and more all the time. I suppose all the parts store ones are Chiney now.

 

I came across the same issues the last time did brake work!

My replacement wheel cyls. all came with those damn mm bleeders. So replaced with some nice used one's that, I got at PnP off a few vans. Now back to standard sizes

Orich

 

I got the rears bled last night but I couldn't get the fluid to flow using a vacuum pump and canister. I tried with the pedal up and with the pedal partially depressed.
I was working alone so I had to depress the pedal and hold it down with a stick wedged between the pedal and the seat. Then crawl under the truck to open and close the bleeder. Then back to the cab to let the pedal back up and once again hold it down with the stick. It was slow moving but my woman is back and will do all the up and down pedal work tonight to finish the fronts.

What do I need to do to get the fluid flowing with a vacuum pump system?

 

One problem you may run into, run the self-adjusters all the way out as far as they can go, so that the shoes are pressed tight against the drum. What can happen is the rubber cups in the wheel cylinder will cover the bleed ports if they aren't extended all the way.

Had no luck with a vacuum bleeder I bought from Griots. I tried everything I could think of to make that damn thing work. May be defective. Bet they are slick when they work. The "speed bleeders" work excellent, every wife should think about these as a gift to hubby, if she wants to avoid marathon brake pumping sessions. Four (4) total are required.

 

Yep. I have Speed Bleeders on my truck. BIG time saver.

 

Do you still have the factory brake valve? Is the wiring connector plugged into the switch sticking out of the valve? Is the brake warning light on the dash lit up?

 

The wheel cylinder cups aren't in the way, at least in the rear, because fluid does come out when I opened the bleeder with the pedal depressed.

The brake warning switch is connected but I haven't ever verified the circuit. The light isn't on in the instrument cluster but since I haven't verified whether the circuit works or not it doesn't mean much. I don't know if much of anything works in that factory cluster, the truck has all aftermarket instrumentation. I can use a multimeter to check the switch once I get the fronts done. That way I can be sure the valve is centered.

Putting my finger over the end of the vacuum hand pump it can create about 15" of vacuum, probably all it can do at 7400 ft. Connected to an open bleeder I can't get it to that level. I didn't look to see exactly how much it was creating but it was very low on the gauge, probably below 5". I've used a different vacuum bleeder kit on many different vehicles...but not this kit on this truck before.

Speed bleeders would probably be a week away...I doubt I could find a set in Laramie.

 

The brake valve doesn't have to be powered up through the electrical system of the truck to determine if the valve is shifted or not.

The switch can be checked with meter, set to ohms, to determine if the pressure differential valve spool inside is centered or, if it's off-center.

Unplug the wiring connector from the switch sticking out of the valve body. Place one meter lead on the prong sticking up inside the switch (where the connector would plug into the switch). Touch the other meter lead to the body of the brake valve assembly. If there's no reading on the meter (infinite resistance), the valve spool is centered --this = good.

If the meter reads a resistance value, the spool has shifted off-center and will have to be recentered.

--done another way: if you have a meter with an audible feature, if the meter doesn't beep, the pressure differential valve spool is centered. If the meter does beep, the valve spool is off-center.

Looking down into a '68-up brake warning switch, you'll see two prongs (pictured below). If you have a '67 switch, it will only have one prong for the electrical connector.


If the valve is shifted, you'll get a resistance value something like this (or, a 'beep' if your meter has an audible feature).


If the valve is centered, there will be no resistance (or, no 'beep').


This check can be done with the valve on the truck. You would only be unplugging the electrical connector to the switch to read it out with the meter.

 

Lots of people report good success "gravity" bleeding. Just make sure the M/C stays full. Open a bleeder and let it drip. Rinse lather repeat.

When I was in the Army every unit tool room had a hydraulic handcart to bleed aircraft brakes, pressurized with nitrogen. It probably cost a small, er, huge fortune. $30k iirc.

For whatever reason nobody hardly could ever get them to work, so nobody ever used them. What all the crew chiefs did in practice, usually the maintenance test pilot or somebody would bolt an old hand crank hydraulic hand pump to a board, couple some braided hose to it along with a few of those blue AN fittings, and Bob's Yer Uncle.