"DANGER RIDE"! There was a "reallity" show on TV (maybe still is) about El Rey's Garage in Venice Beach and some "hillbilly hood rat" called Brothr JD who would drive some old hoopty home with sketchy brakes. He'd get going down a hill and shout "DANGER RIDE"! I took my old '59 Kurbside step van out after a long sit and headed down hill. Everything is down hill from the mountain I live on. Next thing I know I've got no brakes and the emergency brake (driveshaft type) isn't even slowing me up. All I could hear in my head is Brother JD yelling DANGER RIDE! I guess I better dump this single pot master cylinder and get a dual. This step van is on a Chevy 10,000 lb GVW with 19" wheels. Not sure what dual master cylinder I should be looking for.
Did you try the brakes, before you started driving? Usually it's a good idea, if something's been sitting for a while. And after your adventure, did you figure out what's wrong with the brakes? If they lost fluid, that means there's a leak somewhere, that you probably ought to fix.
Although you painted Borat' s van, I wouldn't trust his brake work. Sent from my SM-S320VL using Tapatalk
Oh yeah, I wouldn't leave my house without pumping the brakes. They felt a little mushy but I don't drive the thing very often and thought it might be normal. No wet spots at the wheel cylinders. I assume the single pot master cylinder plunger is bypassing. I haven't bothered to check it thoroughly because it's going in the trash anyway and getting a new dual pot. I just need to figure out what will work.
The single pot will work....if you keep up with maintenance. If you can't do that, then I guess a dual will give you a little bit better chance of stopping when one side goes out, if you set it up properly. We can guess what chassis it is, but pictures would help a bunch. I have a 55 2nd series step van here, might be similar.
>> "I guess I better dump this single pot master cylinder and get a dual. This step van is on a Chevy 10,000 lb GVW with 19" wheels. Not sure what dual master cylinder I should be looking for. Start by finding out what is the cylinder diameter of your single pot master cylinder. Then search for a dual pot master cylinder with the some cylinder diameter. Note that the replacement cylinder needs to be for drum brakes in both front and back. I did this for a 1959 Ford F250, maybe 30 years ago. I used the paper catalogs at a friendly independent parts house. I had to add an adjustable proportioning valve on the rear brakes, as the rear brakes locked up first.
All joking aside my 2c opinion is as others said check for leak(s) first. Then, to me, it's all or nothing. Nothing is something...fixing/rebuilding what's there. All would be new everything, disc brakes, lines, master, etc. Again...my 2c. If it's in good running shape I'd say it's worth it. Good brakes are #1. A mishap would cost more that an all new system. Sent from my SM-S320VL using Tapatalk
it might look like this....I think the 3 bolt pattern was pretty common on Fords in the 1940s and later? The shock bracket might get in the way if you use a simple plate adapter. Be sure to test the system with a bleeder open after you get it all converted, make sure it still has brakes (bleeder open simulates a line breaking, etc)
Redesign a 50 year old system that until now worked just fine because it finally needed some attention? That makes ZERO sense to me. Bring it back to good service condition as is and move on.
Guess you have never experienced a total brake failure? Low millage 1956 F100 shop truck, well maintained, rim cut into the brake line, pedal went to the floor. Battered old Econoline, not mine, pedal went to the floor in my driveway. 1959 F250 beater truck, mine 30 years ago. System got "leaky", replaced all wheel cylinders, all flex lines, upgraded to a dual master cylinder and adjustable proportioning valve while I was at it. 1962 Volvo, same story as the F250.
Yes I have. All the vehicles you listed above had a Factory installed handle mounted under the Dash. It was called an Emergency Brake. When necessary they will actually stop the vehicle in place of the Brake Pedal.
They will eventually stop... A working brake system has 8 brake shoes applied, the Factory installed handle applies only 2 brake shoes. 55 years ago, when the F100 brake pedal went to the floor, the previous stop was at a crosswalk with a line of kindergarten kids in the intersection. Gave me a lesson that I never forgot.
when a system with a dual pot master cylinder fails, you only get two brakes....if you're lucky. Parking brakes are good. But relying on the transmission parking brake on a heavy vehicle like a bread truck, might be pushing your luck. They don't work so well when they're in good condition, and most of them are not in very good condition today.
Guess you never experienced total brake failure WITH a dual pot master cylinder? I have.....the master cylinder had very low time on since the build....completely failed coming down an off ramp in SoCal.... no warning at all. Bought another one but a reputable brand and haven't had an issue since. I drive and have driven cars with single pot master cylinders for 30+ years and that was my first failed master cylinder.
One place to error on the side of caution is the brakes. I would update as much as I could afford to. Years ago, those brakes were sufficient, but back then, nobody had anti-lock brakes and cell phones.
I bought a car from a guy who had replaced the 1" single with a 7/8 " dual MC and use a longer / differant ratio pedal assy... The car would not brake at all, it just went to the floor, pumping really fast helped a tiny bit to slow it down. A 1 1 1/8 MC solved the issues. People screw up a lot of stuff while trying to improve something sometimes...
That's good. What works for, works for you. You state the '56 was well maintained. If so how does a rim cut into a brake line? Apparently there was some sloppy work done. Battered old Econoline.....That speaks for itself. Clik himself stated the pedal felt mushy and it had been some time since he had driven the vehicle. As a qualified Monday Morning Quarterback my thought is, he should have investigated that further. The advantages of a dual pot are clear. There are some variables that are worth discussion. Attributes of..... The single pot system It's simple. There is less to go wrong. It's OEM so there's no parts scramble. On odd vehicles with little aftermarket support, It may be the best option rather than a hodgepodge of parts that may or may not work as hoped. The dual pot system It too can be fairly simple. You have 2 separate circuits in the same master. There are plenty of options for cylinders and pedal linkage. Both systems will clue the operator of problems, most of the time. Disadvantages of.... The Single pot system The single circuit, when it goes so does the primary system. To operate this system requires maintenance and inspection almost to the extreme. It also requires a secondary system just as well maintained with the mental preparation to use it. It demands a much more attentive driver. You should not ride in a vehicle with single pot brakes.....you have to drive it. The driver must know the vehicle and be prepared to park it if any clue of trouble presents. The Dual Pot system The main disadvantage is the false sense of security especially on retrofitted vehicles. Since there are so many options, many times the parts do not work as they should. This could be due to pedal linkage. Depending on how a system was retrofitted full use of a circuit may be impossible and in reality it's a dual master that for all practice purposes is only using 2 wheels to brake the car. Along these lines one circuit could be faulty unbeknownst to the inattentive driver. Clues to braking problems may not be taken seriously. Many will run dual pots with a nonexistent or unmaintained secomdary system. Since the system is more complex there"s more points of failure. The loss of the front circuit may have the same result as the total system loss of a single pot as mentioned above. One functioning circuit may or may not stop the vehicle. The dual pot system should be just as scrutinized and meticulously maintained as a single pot system. A retrofit needs to be highly scrutinized and in confirmed working order rather than parroting what's done on the internet. I'm not going to say the single pot is dangerous and the dual pot is....safe because neither is true. Neither is true if you switch that statement around. Any brake shop will tell you the sorry state of brakes on a lot of late model vehicles. It's probably the most neglected system on a car. How many times do you hear metal on metal in traffic and see the black front wheels? If a driver/builder has that plug and play mindset of today a dual pot is about their only option. Another thing to consider is what type of driving....... " He left the road at 90 that's all there is to tell".........At ludicrous speed, it makes no difference. I'm comsidering a stock Model T. It's on my bucket list. Now there's a car with no hint of modern brakes. I live in an area I could drive such a car daily if I chose the time and the route. What works for me in rural Alabama may not work for someone in the urban interface of Tulsa, Dallas, Chicago or LA. Just like single pots....Should stock Model Ts and As be banned? No....Whatever a person chooses to drive should come down to dillagence, judgement and responsibility.
Amen to that. I have had two different dual brake Chevy trucks (95,07)fail me and both times Zero brakes. Chevy has had a problem with their brake and gas lines for quite some time.
Give ABS Power Brake in Orange, Ca a call (714-771-6549) and tell them what you want to do. He will custom build you a master cylinder for your application. Been a while since I had him build me one, but he was really reasonable when he did mine. Sent from my SM-G955F using The H.A.M.B. mobile app
Find a similar weight vehicle with drums that has a dual MC Probably a late 60s to early 70s application I sometimes use rockauto for pics and part numbers. Manufacturer of vehicle is not important. find a dual ms for a drum/drum vehicle of similar GVW. A late 60s p20/30 van may be a good start Then ya get to fab a mount and modify the rod. The brake lines are easy Totally worth the effort.
This one has two bolts rather than being cast as a housing and master combined, luckily. So, fabbing a mount may not be necessary.
I have a 57 step van. The size under yours. It had a frame mounted booster. It was located on the passenger side I’m using a booster and ms assembly from a g20 van. But my build is different with non hamb friendly suspension.
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