Keeping rear calipers adjusted

[steelworker77]

Just installed WH's rear disc brake kit along with there super 9 housing.

Set the brakes up with the 1/16-1/8" gap with the E brake arm as the videos showed, bled everything and it has been great.

Have about 750-1000 miles on it and noticed longer pedal travel so checked the adjustment again and now its got a strong 1/4 to 5/16" of gap.

I use my e brake regularly as I am on a 5 speed and it seems like its not self adjusting as it should.

Am I missing something here before I go back and re-adjust again?

 

[ksagis]

More brake pedal travel or parking brake pedal travel?

(Get ready for a variety of opinions on the parking brake mechanisms if these are the Caddy caliper conversion)

Did you confirm that the backing plate was parallel to rotors? If not, maybe the pads needed to wear to get to parallel.

 

[steelworker77]

I noticed I had more pedal travel so went down and checked the parking brake arm and it was out of adjustment. Yeah they are the caddy calipers. Everything parallel and spaced correctly. Seems to be a somewhat common issue from some reading I was doing. Kinda wishing I just would have stuck with drum brakes. I was converting from a small to big bearing rear so had to get new brakes and they were basically the same price so figured why not.

 

[ntsqd]

Rear Disc Brakes - Cadillac/GM calipers

Tech article by Lars Pedersen (Lars) The addition of rear disc brakes is a popular upgrade for early Broncos. Lots of creative people have accomplished this mod using components from Lincolns, Cadillacs, Ford Explorers and others. These days...

classicbroncos.com

Good luck.

 

[ksagis]

Doesn’t seem likely that either pad wear or parking brake issues being the issue in less than 1000 miles from initial install if the original install was solid.

Maybe check if things are still parallel? How much clearance is there between pads and rotors?

 

[ntsqd]

Most likely it is because there are no wear/corrosion replacement parts available for the parking adjusters, and no one makes those calipers new.

 

[ksagis]

I need to look at the mechanics of the parking brake some more, I had assumed that if the mechanism was not operating correctly that as the pads wore that the parking brake mechanism wouldnt take up the wear.

@ntsqd, are you indicating that the mechanism can result in loss of proper pad clearance not associated with pad wear?

i.e. the mechanism somehow “loses” its adjustment?

 

[ntsqd]

I don't know enough about the actual design of those parts to know if that is possible or not. What I do know is that two friends, both very mechanically talented, could not keep those calipers in adjustment no matter what they did or tried. Both have long ago abandoned them. The one with an EB has gone to the Explorer RDB system and the other went back to drums.

I'm told that there is a hydro-mechanical combo service / p-brake caliper out there that does work, but I've never seen one. Reportedly a very talented EB owning Canadian fabricator is using them, and if he says that they work I'm inclined to believe him.
Those that I have been around, the two versions of the GM, a really rare Mercury caliper, and some that were designed for my then employer's commercial/industrial customers never really worked very well. Within the space constraint of a hydraulic caliper body it is pretty difficult to generate enough mechanical clamping force for p-brake use.

 

[steelworker77]

Thats what I wasnt sure about if they were new or rebuilt. Seems that if they were rebuilt getting them to self adjust is almost a lost cause. I readjusted last night. If they dont hold adjustment again they are coming off and I am going back to drums. Should have trusted my gut on that one.

 

[ntsqd]

Have a look at the Explorer based RDB kits. All of their functions work a lot better. Last such kit that I bought, several years ago, was ~$500 shipped and I found it at Moser Axles.

 

[toddz69]

Most likely it is because there are no wear/corrosion replacement parts available for the parking adjusters, and no one makes those calipers new.

They actually do make new ones now - Chinesium repops to the rescue. And they work just as well as the originals did.....

Todd Z.

 

[ntsqd]

Which is to say not very well. At least that's been my accumulated experience & observation over 30-odd years.

 

[toddz69]

I'm told that there is a hydro-mechanical combo service / p-brake caliper out there that does work, but I've never seen one. Reportedly a very talented EB owning Canadian fabricator is using them, and if he says that they work I'm inclined to believe him.

He uses some late '80s/early '90s Varga calipers from Fords. I tried them at the 40th and they held great!

The rear calipers on my '12 Mustang seem to work well too (much smaller tires, obviously). MP Power Brakes uses them in their rear disc kits now. https://mpbrakes.com/product/db3572...sc-brake-conversion-kit-1957-1972-ford-f-100/

Todd Z.

 

[steelworker77]

Have a look at the Explorer based RDB kits. All of their functions work a lot better. Last such kit that I bought, several years ago, was ~$500 shipped and I found it at Moser Axles.

Was just checking out Moser's site. This definitely seems the way to go. Appreciate the help.

 

[ksagis]

Was just checking out Moser's site. This definitely seems the way to go. Appreciate the help.

$500 would be a bargain, got a link to what you were looking at by chance?

 

[ntsqd]

As stated that was several years ago. At roughly the same time you could have put together a "kit" for the Expedition RDBs (same as the Explorer system only larger & doesn't fit inside a 15" wheel), including the main bracket, off Rock Auto for just over $500.

 

[steelworker77]

https://www.moserengineering.com/product/ford-explorer-disc-brake-kit/

I saw this one and honestly didnt get a chance to even look at the dims to see if it could be made to work. Was gonna check it out when I get home tonight. I definitely like the parking brake setup more!

 

[ntsqd]

The "Torino" bearing housing requirement is likely the worst part, I don't know of a good way to work around that.

 

[toddz69]

https://www.moserengineering.com/product/ford-explorer-disc-brake-kit/

I saw this one and honestly didnt get a chance to even look at the dims to see if it could be made to work. Was gonna check it out when I get home tonight. I definitely like the parking brake setup more!

And this one's cheaper:

https://www.quickperformance.com/Fo...tMraelcSfzlhiWhy3RYJZ3I25RCQp_0UaAobgEALw_wcB

Todd Z.

 

[ksagis]

And this one's cheaper:

https://www.quickperformance.com/Fo...tMraelcSfzlhiWhy3RYJZ3I25RCQp_0UaAobgEALw_wcB

Todd Z.

Brake Meister for the win!