F250 front brakes drag. Help!

[guhfluh]

I'm so indecisive! Ha! I just put on a pedal return spring I had laying around and tried it. It works great.


I think I'm going to use it for a while, see how it does and move on to other projects, like radio and A/C...I'm just so tired of messing with it.

[ultraranger]

It's just too hot and humid here in south Arkansas to fool with swapping my '69 Ranger over to front discs but, in a few weeks when the weather cools off, I'll be swapping the '77 F-100 front beams and discs onto the truck. I'll also be adding a power steering gear box, power steering pump and brackets, a dentside front sway bar and my freshly rebuilt tilt steering column.

[guhfluh]

Ooo, power steering is another one of my projects to do, but a/c and p/s bracket combo is hard to find for a v-belt 300. I have a gear box, pitman arm and short column shaft to swap into my 4 spd column, but the gear needs rebuilt, the pitman is the wrong year for my linkage, and I don't have a pump, lines or brackets yet, so it'll be a while. I'm planning on getting Redhead to rebuild it and swap in a quick ratio.

[ultraranger]

As far as I know, all the power steering gear boxes have the quick ratio (compared to the manual steering gear boxes). However, some power steering gear boxes have quicker ratios than other power steering gear boxes.

I have a wrecking yard Saginaw power steering gear box I pulled off a '78 Ford truck but, I went ahead and bought a newly rebuilt Saginaw box from O'Reallys. I believe it's a 17.5:1 ratio gear box. I pulled the pitman arm off the wrecking yard donor to put on the new box so, I'm good there.

I had a really hard time getting the steering gear box and the power steering hoses (for a 240/300) from O'Reallys. It showed these parts on their website with photos, descriptions and part numbers. --I always write down the part numbers ahead of time and have them in hand when I go into the store (they act like they're confused a lot of times when trying to buy/order something from them). Anyway, I give them the part numbers. They tell me they can't get these parts because not all the parts listed on their website are available at every store (WHAT THE ...!?!?!). Their reason was that these parts weren't available in this region, to my local store, but I could order it online. (That's real convenient).

I leave there and go to NAPA to order the parts. They can get the hoses but can't get the power steering gear box (getting really irritated now). At this point, I told the people at NAPA to order the power steering hoses (pressure & return). I came home and ordered the gear box through the O'Really website. The gear box was delivered to my door a few days later and the hoses came in the day after I ordered them, which I picked up at the local NAPA store.

The rebuilt Saginaw power steering gear box part number from O'Reallys is; Master Pro 27-7504.

The (240/300) power steering pressure line part number from NAPA is; 7-1490. The NAPA power steering return hose part number is; 7-1559.


I pulled my power steering pump and brackets off an '82 Ford pickup that had a 300 six in it. It has the Ford C-2 style pump. I'm not a big fan of the older Ford Thompson pump (the one with the metal back cover/reservoir and the small tube that comes up with the dipstick in it). Every old Ford I've driven with one of those power steering pumps on it were overly boosted and too sensitive to steering input. They tend to whine a lot too. I'll turn my wrecking yard C-2 power steering pump in for the core but, I already have the newly rebuilt C-2 pump (from O'Reallys). It's Master Pro part number 20-6240F.

When I got the power steering pump and brackets off the 300, in the '82 Ford pickup, I also grabbed the AC compressor mounting bracket.

Power steering brackets, power steering pump pulley and water pump pulley --after I bead blasted and painted them.



What the parts looked like when I had just gotten home from the wrecking yard with them. --AC compressor bracket is shown at the far right of the photo.

[guhfluh]

Feel free to just send all those parts over to me:)

Thanks for the numbers, they'll come in handy I'm sure! I actually had an 85 F150 with A/C and P/S that I got the engine and transfer out of, but like a dummy, I left the brackets and everything in the truck when my buddy scrapped it. There's another early 80's Ford in a buddy's yard I need to go back and check on, but I think it may have the brackets and pump I need.

The quicker ratio guts are from another unit that they can swap in, and I want to say they're 16:1. I have 16:1 in my Dodge and I like it, though it is pretty weak and I'd like more assist. I just like a quick ratio and believe I'll want it even more since I plan on keeping the big 3 spoke wheel.

[ultraranger]

My '68 Mustang (originally) came with power steering. However, when I bought it (September 14th, 1982 --I was 2 weeks away from being 16 then), the power steering pump and brackets were missing from the 289. Only the slave cylinder and loose hoses remained.

Early Mustang steering gear boxes don't have hydraulics going to them like the Saginaw boxes in the trucks do. They have a slave cylinder. With no hydraulic pressure on the slave cylinder in my '68 Mustang, the steering was really loose and sloppy. I ripped the slave cylinder out and installed a manual steering drag link.

There's a difference in the early Mustang steering gear boxes though. Mustangs with manual steering had 19:1 boxes and ones with power steering (like my '68), had 16:1 gear boxes. A quick ratio box with manual steering equals some difficulty turning the wheels, when sitting still (although it wasn't too bad) but, it did respond really well to steering wheel input out on the highway.

....if I send you the power steering brackets and whatnot I have, that just means I have to re-find this stuff, for my truck, all over again.
Unless something happens to get in the way, I plan to make a trip out to the wrecking yard sometime this weekend --while I'm off on a long weekend. I'll keep an eye out for some (300) power steering and AC brackets, --in the event it turns out your buddy doesn't have what you are needing for your truck.

[guhfluh]

So, I'm revisiting this just in case someone is still following.

I haven't replaced my sticking booster, though I should have already. I'm not sure what happened to that warranty booster I supposedly had coming.

I still feel that the brakes are dragging some at times and possibly leading to a vibration I have been fighting. I have decided to finally go ahead and work on the breaks again. I am ordering 2 new Bendix rear drums and a correct combination metering/proportioning valve. I may also purchase a 10lb residual valve for the rear in hopes it helps some also. I always want to pump the pedal once before applying to get a firmer pedal that's further from the floor. It will still stop well if I don't pump it in an emergency, but feels like I'm running out of pedal room. I have yet to lock up any wheels, it just stops QUICK, especially for a 3/4 ton crew.

I am contemplating swapping out the booster. If I spend money on purchasing another booster, I would rather "upgrade" to a 68+ compatible one. Probably a 8" dual diaphragm. The "problem" is that I just upgraded my 67 pedal assembly with a Mustang Steve bearing kit. I'll have to purchase a new kit, or at least source new outer bearing retainers if I change the pedal hanger assembly as well as change the brake light switch over to the new style. I'm wondering if there might be a way around it by using a cantilever booster and bracket and redrilling the pushrod arm to fit the 67 pedal arm location. Will the cantilever bracket and booster decrease the amount of pedal travel required? That is what I'm hoping for. Is the 68-72 brake pedal arm ratio(the distance between the pivot and the pushrod hole) the same as the 67?

If there's no ratio benefit to a cantilever bracket, I won't go that route. If there's a difference in pedal ratios between 67-68 or if I just won't have enough pedal stroke,
I'll probably just quit my quest of mixing and matching, and just change over to 68+ everything.

[ultraranger]

So, I'm revisiting this just in case someone is still following.

I haven't replaced my sticking booster, though I should have already. I'm not sure what happened to that warranty booster I supposedly had coming.

I still feel that the brakes are dragging some at times and possibly leading to a vibration I have been fighting. I have decided to finally go ahead and work on the breaks again. I am ordering 2 new Bendix rear drums and a correct combination metering/proportioning valve. I may also purchase a 10lb residual valve for the rear in hopes it helps some also. I always want to pump the pedal once before applying to get a firmer pedal that's further from the floor. It will still stop well if I don't pump it in an emergency, but feels like I'm running out of pedal room. I have yet to lock up any wheels, it just stops QUICK, especially for a 3/4 ton crew.

I am contemplating swapping out the booster. If I spend money on purchasing another booster, I would rather "upgrade" to a 68+ compatible one. Probably a 8" dual diaphragm. The "problem" is that I just upgraded my 67 pedal assembly with a Mustang Steve bearing kit. I'll have to purchase a new kit, or at least source new outer bearing retainers if I change the pedal hanger assembly as well as change the brake light switch over to the new style. I'm wondering if there might be a way around it by using a cantilever booster and bracket and redrilling the pushrod arm to fit the 67 pedal arm location. Will the cantilever bracket and booster decrease the amount of pedal travel required? That is what I'm hoping for. Is the 68-72 brake pedal arm ratio(the distance between the pivot and the pushrod hole) the same as the 67?

If there's no ratio benefit to a cantilever bracket, I won't go that route. If there's a difference in pedal ratios between 67-68 or if I just won't have enough pedal stroke,
I'll probably just quit my quest of mixing and matching, and just change over to 68+ everything.

Too much information to have to retype here but, I'll give you this link on the 4 basic styles of the F350 style dual diaphragm boosters.

The booster in the second picture I show is the type I have on my '69 F100. The photo below that is one of two spare '74 dual diaphragm boosters I have. --the '74 donor booster in the picture is about to be installed in a '72 F100 I'm currently converting to front disc brakes. --well, the booster brackets and the hard plastic boot will be installed. The donor booster will be turned in as a core for a newly rebuilt booster.

http://www.ford-trucks.com/forums/14407 ... st16380503

[guhfluh]

Thanks for the link Steve. I had read through it and from what I can tell, the cantilever bracket does increase pedal effort and increase booster pushrod throw. All of the pictures online of new ones however, show the cantilever bracket assembled incorrectly which is what added to my confusion.

The newest update is I think I may have finally found the biggest issue I have had all along with the dragging brakes and spongy pedal. The driver side caliper. The brakes had been progressively getting worse to stop. Spongy pedal, long throw and pulling to the right hard at times when braking. Yesterday on my way home I started pumping the pedal and applying it HARD while I was waiting for a red light, just to see if they would pump up, bleed down or bottom out on the firewall. They seemed to pump up some. When I got home a block away, I could tell the brakes were dragging bad, but they felt GREAT! FIRM pedal and I could lock them up at will for the first time ever. I jacked up the front and checked both wheels and the driver front was locked up pretty hard. I diagnosed it from the booster back down to a piston sticking in the bore. Nothing would free it up. Come to find out, that was the side I couldn't get a reman for and had to rebuild myself. I do remember one piston being very hard to move compared to the others and maybe something with the bore. I could have the seal reversed for all I know. I now have a reman on order from O'Reilly and plan to pull the bad one apart today.

Another thing I found that I need to know. For the 2001 Ford Explorer master cylinder, which port is for the front brakes? Primary piston (towards the booster) to the front brakes? I have the primary piston in the master (the one towards the booster) going to the rear drums. I have the secondary piston (the one furthest from the booster) going to the front calipers. I thought it was supposed to be the other way, but there must have been some reason I didn't plumb it like that.

[guhfluh]

So, I've just pulled apart the driver side caliper. The pistons did NOT want to move with anything under 100psi. I had to crank the air up over 120psi to get them out. The Pistons looked pristine, but one of the piston seals had its edges extruded off, or sheared off during install. The strange thing is that there is evidence of both top and bottom edges doing it. It's probably from me having issues and pulling it back apart, checking and reinstalling it the other direction. I've researched and found out that they are square seals, so either direction is the same. Once I checked out the Pistons and seals, I reinstalled them and noticed that with them lubed with brake fluid, they move in and out no problem now. I checked to make sure the dust boot wasn't causing any issue and it doesn't make a difference if it's installed or not. I DID notice that the one piston that has the bad seal does NOT retract as far as the other, when only a light amount of pressure is applied, just enough to flex the seal, but not move the piston through the seal. O'Reilly has ordered a new reman caliper for me, but it'll be a few days.

The other problem I found is the stupid caliper mounting bolt bushings that go into the mounting bracket on later model 72+ F250 and F350 dual piston caliper trucks. I had two that had fallen out. One on the lower outside and one on the upper inside. The bushings are also TIGHT around the bolts. I can not see how they allow the caliper to slide at all. I can take one of the rubber bushings and install it over the bolt outside the truck and hardly slide it at all. Once it's installed in the caliper mounting bracket, it's slightly smaller ID doesn't allow the bolt to slide freely at all. I'm about to epoxy the bushings into the caliper mounting bracket and "hone" them out some, along with polishing the bolts. I guess I'll try to clean the inside of the caliper mounting bracket though hole and fill it with grease to try and keep the bolts lubed?

[ultraranger]

The MC port closest to the firewall is the primary port (circuit goes to the front brakes). The MC port closest to the radiator is the secondary port (circuit goes to the rear brakes).

The caliper seals are square cut. The seal distorts when the pedal is applied and the piston moves outward in the caliper bore. When the brake pedal is released, the seal returns to its normal shape while simultaneously retracting the piston back into the caliper bore.

https://youtu.be/bPgLdxQbiWI

[guhfluh]

I knew the piston seal did the retracting, I just always want to picture it as a lipped seal rather than a square seal. I'm pretty sure I'm having a problem because of the seal that is missing it's edges/corners doesn't deform correct.

Now, what I still haven't looked up is, other than reservoir size and one pushing the other, what is the difference in "primary" and "secondary" master cylinder pistons. Front port doesn't always go to the rear brakes...

[ultraranger]

All of the Ford MCs that I've delt with, whether a conventional style cast iron or a conventional style in an aluminum body or, whether a more 'modern' design cylindrical aluminum body/plastic reservoir MC --SN95 V6 Mustang, Fox Mustang, '95 Explorer, '96 Mustang GT hydroboost, '03 Mustang Mach 1 hydroboost, were plumbed with the rear most port going to the front brakes and the forward most port going to the rear brakes.

There MAY be SOME Ford MCs plumbed the opposite of this but, I've never encountered them.

The reproduction Corvette MC that's commonly used in aftermarket brake setups is plumbed with the forward most port going to the front brakes and the rear most port going to the rear brakes. --just the opposite of a typical Ford brake MC.

[guhfluh]

I don't believe mine was originally plumbed that way and why when I copied the original lines, I hooked it back up that way. I'm used to all the Dodges I work on being front to rear and rear to front, why I questioned it when I just saw it. I still haven't looked into why there is any difference yet though.

[ultraranger]

Of the Ford MCs I've messed with, only the '87-'93 5.0L Fox Mustang MC had an odd-ball bore size -- 1-3/16" primary piston with a 13/16" secondary piston. All the others had consistent bore diameters on the primary and secondary sides, whether that was 15/16", 1.00", 1-1/16, 1-1/8" or 1-1/4".

There's a primary and secondary seal on each of the primary and secondary pistons inside the MC. The two seals on the primary piston are further apart than the seals on the secondary piston. Pressure coming out of both MC ports will be the same but the volume of fluid movement will be slightly less on the secondary side piston of the MC, compared to the volume being displaced by the primary side piston.

This is a photo of some Ford MCs I was messing around with that illustrates the difference in distance between the seals on the primary pistons, compared to the seals on the secondary pistons.

Lincoln Mk VII/Mustang SVO 1-1/8" aluminum bodied conventional style MC on the left. '87-'93 5.0L Mustang 1-3/16" pri. / 13/16" sec. MC at top right. '99-'04 SN95 V6 Mustang 1.00" MC at bottom right.