Brake booster

[Johnson]

Yeah, I guess I didn't look close at it. The one on my truck just has the 2 smaller ports coming off it, so I will have to buy a new one like the one on the left.

[fordman]

i'll send you that one for 5.00 shipped.

[70_F100]

If you don't have a vacuum tree near the rear of the engine, there should be a plug threaded into one of the runners on the intake.

Just pull that plug and go to your local auto parts and get a fitting for 3/8 hose on one end and 3/8 NPT on the other.

[Johnson]

I wimped out on installing the power brakes....to much modidication to get it to work...

I only paid 100 bucks for this truck so you can imagine the shape it's in. Hate to invest to much into it and never get it back...

I did replace the master cylider along with all the brake shoes. It actually stops now, AND I don't have to pump the brakes anymore!!

[OldRedFord]

Didn't read all of your first post.

If the booster is missing, your easiest route is to just find a donor truck and remove the whole booster assembly, along with the brake pedal and linkage. Rebuilt boosters will NOT come with the entire push rod assembly.

Your master cylinder will, most likely, bolt right up to any of the boosters.

My 70 F100 came without power brakes. First, I bought a used booster that was correct for the truck. That one went bad, and I replaced it with one from a 77 F150. I have used the same master cylinder with all three arrangements.

I have the booster, the push rod that pushes on the master cylinder is missing. Now the rod that hooks to the pedal is there.

Like when I took off the master cylider, there is nothing to push on the piston.

So what I have its

(master cylinder) {missing part} [Brake booster] (push rod that hooks to pedal)

[fordman]

thats wierd. i dint know that part came out of the boosters. i have a bad booster i might be able to get that part out of for you.

[robroy]

Hi Tim! Like Fordman, I also have an old, funky booster with that part in it (it's an adjustable push rod). It doesn't look like it comes out really easily--I went in the garage earlier and tried. I could pull this out and mail it to you for free if you want it. Or I could post a photo of it if you're interested.

Robroy

[OldRedFord]

Hi Tim! Like Fordman, I also have an old, funky booster with that part in it (it's an adjustable push rod). It doesn't look like it comes out really easily--I went in the garage earlier and tried. I could pull this out and mail it to you for free if you want it. Or I could post a photo of it if you're interested.

Robroy

Id like a picture if its not too much trouble.


Just to make sure everyone is on the same page as me...



If I remove the master cylinder (replaced the rusty one in the pic) what is suposed to actuate the piston in the cylinder that would be between that and the booster? That is what is missing.

If more pics are needed I will see what I can do.

[FORDification]

The pushrod for the master cylinder on a manual-brake truck is held in with this retainer clip. The pushrod WILL come out if you pull like hell.


Here's a side-by-side comparison of what you'd be dealing with...the master cylinder and pushrod used with manual brakes, and the power booster/master cylinder that you'd be using. The power booster has both pushrods (front and rear) incorporated into itself...


When you separate the master cylinder from the power booster, you can see the pushrod. In many cases this pushrod is adjustable....


...and this is how that adjustable pushrod between the booster and MC should be adjusted, according to the factory shop manual:

[OldRedFord]

You got to wonder, why somebody would pull that out of the brake booster assembly?

[robroy]

Hey Tim! It's possible that the pushrod wasn't pulled out on purpose. On a rebuilt booster I ordered a while back, that pushrod was simply resting in there--it would almost fall out if you held the booster upside down.

Robroy

[robroy]

Id like a picture if its not too much trouble.

No trouble at all Tim!

Here's the booster the pushrod came out of. It used to be installed on #50 (1972 F250 8,100lb GVW).



Here's the pushrod installed in the booster body.



Here's the body after I yanked the pushrod out. It actually came out like it was built for that--I just had to give it a good pull!



Here's the pushrod. I was surprised at its shape! The link under this small photo goes to a full resolution edition of the same photo. As you can see in the photo, the whole thing's about 4" long. Its circular base is around 1/2" long.


http://www.robroygregg.com/Number50/IMG_3610s.JPG

And the seal that's above the circular base is about 1 and 7/16" across.



Tim, if this is the part you've been looking for I'd be happy to send it to you. I don't have any use for it!

Robroy

[fordman]

do i feel better or what? when i saw your first 2 pictures i thought yours is bigger than mine.



but then i went out and got pictures of mine and figured out why it looked bigger than mine. the rod does move out like that.


i couldnt remember what i saw on the other one i have. i couldnt even find its rod. it has disappeared into the twilight zone. just like everything else i thought i had.