Split brake system

gringeltaube

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Very nice! That would help for sure if there was a sudden line burst.
Only problem I see is that in most cases we have a SLOW leak from a rotten hose or pitted cylinder, that goes un-noticed until enough fluid is lost for the MC to continue working.

G.
 

gringeltaube

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Agreed!, very true, IMHO this should be the very first step for everyone thinking about Deuce-single brake circuit-system-upgrades...!

G.
 

Sevin7

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What is a good remote reservoir to get? What size allows for adequate fluid level monitoring? Are there any that folks have used that still allow use of a pressure bleeder (especially of the garden sprayer variety)?
 

skinnyR1

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I have been mulling over possibly installing a split brake system on my truck.

I am intrigued by the hydraulic fuse that is mentioned in this thread. They are used in aircrafts and forklifts, I've discovered thru internet research.

It could be an easier answer compared to modifying to a split system. If there is a line break, the fuse would cut off that line.

Does anyone have any experience or insight into these hydraulic fuses, and which ones would work for our single curcuit automotive applications?
 

Section8

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I will check my master cylinder for it's bore size. I have a M135 but I think they are the same system except M35A2/3 have a baffle valve for return pressure.
I have been looking at most of the brake mod threads.
My thought on all of this, since I am also interested, is this.
Why not use a dual circuit master cylinder for the hydrolic application and then some kind of deadman valve in the airlines for each corosponding axle.
Basically the same thing as the hydrolic fuse.
Most if not all commercial heavy trucks have their airbrakes "Dyno" with pressure loss. Put the same pressure valve before each axle and on air failure it closes. Thus compartmentilizing the effected axle. And since loss of air to the axles on these trucks doesn't mean a lock up, unless I am wrong, the others will still have braking. Might have stiffer pedal but still have braking ability.
This set up would then eliminate the need for a second air pak and added lines, yadda yadda.
Just a thought.
Ready...
Aim..
Fire!!!
Shoot it full of holes.
 

peashooter

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A pinion brake might be one of the cheapest/easiest ways to get an "emergency" brake if the hydraulic system fails. I just saw the other day that Boyce equipment had a kit in the $300-400 range if I remember correct.
 

skinnyR1

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The pinion brake is interesting. I wonder if you could integrate that with the existing e brake and have the driveline brake too.

I wonder how much braking you would really get with that mounted to the front axle.

I guess the question becomes, do you want a better e brake, or build in the redunancy into a split system. End costs would probably be comparable.
 

welldigger

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I will check my master cylinder for it's bore size. I have a M135 but I think they are the same system except M35A2/3 have a baffle valve for return pressure.
I have been looking at most of the brake mod threads.
My thought on all of this, since I am also interested, is this.
Why not use a dual circuit master cylinder for the hydrolic application and then some kind of deadman valve in the airlines for each corosponding axle.
Basically the same thing as the hydrolic fuse.
Most if not all commercial heavy trucks have their airbrakes "Dyno" with pressure loss. Put the same pressure valve before each axle and on air failure it closes. Thus compartmentilizing the effected axle. And since loss of air to the axles on these trucks doesn't mean a lock up, unless I am wrong, the others will still have braking. Might have stiffer pedal but still have braking ability.
This set up would then eliminate the need for a second air pak and added lines, yadda yadda.
Just a thought.
Ready...
Aim..
Fire!!!
Shoot it full of holes.
Uh...the deuce doesn't have air brakes. Just plain old hydraulic brakes. The air pack just replaces a vacuum booster or hydrobooster.

The theory on how to split the system is pretty easy. Just install a dual chamber MC and second air pack. The question is which MC to use?
 

welldigger

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The pinion brake is interesting. I wonder if you could integrate that with the existing e brake and have the driveline brake too.

I wonder how much braking you would really get with that mounted to the front axle.

I guess the question becomes, do you want a better e brake, or build in the redunancy into a split system. End costs would probably be comparable.
I would only use a pinion brske as a hydraulic parking brake ONLY. An emergency stop with a pinion brake would melt that thing long before you came to a stop. Maybe if you mounted one on every pinion flange you may could acheive back up braking but that would be more expensive than splitting the brakes up.
 

Section8

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Ok so we have established I'm an idiot sooo... I will keep going.
If the aik pak is a booster to the brake system on these trucks get rid of the **** thing!! If your gonna do all the work to plumb in a new air pak and lines and dual master cylinder just go full hyrdo boost! Find a ford F650 or Hino or what ever that has a full juice set up with the hydro boost and swap that in.
Just about as much work as trying figure out all this **** about two air paks and dual cylinder volumes.
Seems to have worked quite well for others! Keep the air pak for service tools and such.
Oh by the way master cylinder bore is 1 3/4 inch.
I also believe pinion brakes are illegal for road use.
 
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welldigger

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Hydroboost has been done. It works very well. However, it requires a power steering pump to be installed. To use 2 air packs is very simple. Add your new dual chamber MC and then mount a second air pack to the oppisite frame rail. Then plumb one brake line from the MC to one air pack and then the other line to the second. Then from one air pack to the front brakes and the other air oack to the rear brakes. Thats exactly how the m35a3's and late model air force a2's did it. Not really that complicated. Its just coming up with a master cylinder and a way to mount it. Most medium duty trucks have a suitable MC. Just build a bracket and linkage.
 
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rustystud

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Peashooter sells a new dual circuit Master Cylinder that is the stock set-up. Plus he has stainless lines and hoses. His add is in the for sell section. I bought his lines and hose kit and love it ! I'm also buying a spare master cylinder just in case .
 

outcast

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After having a brake cylinder fail last year I decided to upgrade to a split brake system. I've chosen to go with a late A/F a2 system. The conversion looks straight forward. I've picked up a master cylinder from Peashooter and plan on buying the rest of what I need when cash allows.
 

skinnyR1

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After having a brake cylinder fail last year I decided to upgrade to a split brake system. I've chosen to go with a late A/F a2 system. The conversion looks straight forward. I've picked up a master cylinder from Peashooter and plan on buying the rest of what I need when cash allows.
When your brake cylinder failed, did you have zero brakes, or did you have a couple of brake pumps with marginal brakes before all of the fluid was pumped out? To upgrade to the a/f split system, are you installing the split master, an additional air pack, and proportioning valve? Where is the proportioning valve sold these days, and is it a general item used elsewhere? My truck is a winch truck, so I would also need to figure out a bracket for the PTO level I believe.
 

outcast

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When your brake cylinder failed, did you have zero brakes, or did you have a couple of brake pumps with marginal brakes before all of the fluid was pumped out? To upgrade to the a/f split system, are you installing the split master, an additional air pack, and proportioning valve? Where is the proportioning valve sold these days, and is it a general item used elsewhere? My truck is a winch truck, so I would also need to figure out a bracket for the PTO level I believe.
Lost brakes all at once. I am installing split master cylinder, split air tank, second air pack, and the needed brackets. I do not know of a proportioning valve in the system, however, you will need a pressure differential switch. I believe Peashooter might be able to help you out with that. I'm still sourcing parts as money allows. I'm in no way an expert on the brake system, still learning but this is what I think I know. :) Hope this helps.
 
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