Adding a remote brake resevoir onto firewall

[GB SISSON]

Years ago I bought an early 50's dodge pilothouse pickup to flip. Under the seat was a box with a unit designed to replace the cap on the under floor master cylinder with a fitting with a hose attachment and a small jar with mounts for the vehicle's firewall. If I remember correctly I let it go with the truck because it was spec'd for a dodge. A few years ago I got to thinking about it and I started building one from a brass drip oiler off an old one lung engine. My plan was to use an old ford cap and prepare it to accept a line between the two. I got sidetracked somewhere between trying to decide what to use for the gaskets above and below the glass cylinder and what kind of hose or tube to use. I have never mastered soldering so I had a friend add a vented flip cap onto the oiler and he made some nice brass tabs for attachment. Other than judging, in a show, or a parking lot I can see only positives. I live on a half mile of dirt, usually muddy road. I rarely check my fluid as this act is far more likely to introduce dirt into my clean new system and when I DO check it, it's always full. The positive here is obvious to me. I did a search here and nothing at all searching remote master cylinder for our awkward under floor master cylinder. And yes, I know they aren't always full as I have experienced total brake failure three times in my old broke, early years. Today it's new everything before I hit the road. I will get a pic if I can remember where I stashed the thing. Comments requested, Thanks

[cas3]

Well, first GB I'm glad to hear you are still with us. You have been absent for a few days, I was afraid you tried to make another U turn on a cliff, or had driven thru the chicken coop again . So, on topic, yes, pulling up the carpet or mats to check fluid on the older cars is a PIA. You would be very unhappy with my "converted " 34 hotrod where you need to perform a miracle to put fluid in the master because I refuse to make a hole in my nice original floor. I also like the white plastic thingys on later cars where you can see the fluid level. So, other than an ugly plastic thing, I am all for making life simple for the guy putting fluid in a functional car

[51504bat]

Gary,
2 options for remote master cylinder fill systems that come to mind but I'm sure there are others.

The Wildwood one is plastic and kinda fugly.
Wilwood Disc Brakes 260-10500 Wilwood Master Cylinder Remote Reservoir Kits | Summit Racing
The one from Hwy 101 is more appropriate for an old Ford but definitely more pricey.
https://highway101ind.com/shop/ols/p...939-51-mercury

[GB SISSON]

I found my glass oiler project. Seems this would make brake bleeding, at least in the manual way, a bit easier. These things used cork gaskets when they were oilers. I also have corprene and black cardboard looking gasket sheet. Still not sure if an original cap can be made to work or if it is vented in such a way as this would not be feasible.

[GB SISSON]

Seems we were writing at the same time, then I went to google and found the tin can version, made in Allyn Wa. ! Now I see I was beaten to the punch. Didn't look at the price. Edit: Just googled about hose for brake fluid. EPDM is the only hose that will resist brake fluid, but I gotta say the hyw 101 kit looks like silicone hose I have bought at McMaster-Car for vacuum hose. But I now know that the epdm remnants from my woodie roof will make the gaskets I need for my glass oiler.

[Brian]

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I run the same style as that highway 101 in my 35...I added it at the same time I did the hydraulic brake conversion...to my way of thinking it makes checking fluid so much easier, gives the system a bit of 'head' pressure [easier to bleed], and the system just has that much extra reserve. Because I won't cut holes in my car [didn't want to cut access hole in floor], I mounted the canister on a bracket that I bolted onto chassis with original holes

[GB SISSON]

Brian and CAS, I get the 'hole' thing. I recently installed a 120 hp cummins turbo diesel in a jailbar tonner and didn't drill a single hole anywhere. Hydraulic clutch master cyl went in the horn holes, I fabbed engine mounts to match the existing V8/six mounting holes etc, etc.... Back to the master cylinder thread, seems I want to plug any vent in an original MC cap but moisture could still enter through the flip cap on my oiler but way drier up on the firewall. Anybody know if epoxies like JB Weld are ok with brake fluid? And... I just ordered 8' of gray 5/16" epdm brake fluid transfer hose from speedway. I have a few extra oilers sitting around.

[B-O-B]

G B I doubt that J B weld would work. I don't have an answer for you but sure someone will chime in. Just wanted to mention that I used a paint cup from my touchup spray gun. It has a vented cap & the cap just pushes on for a tight fit. It has the outlet at the bottom of the cup. I just needed to adapt a fitting on my master cly cap & attach a flexible hose from the master cap to the fitting on the cup. Mounted it on the firewall & has worked fine for as far back as I can remember. This is on my 32 hotrod & sorry I do not have a picture.

[GB SISSON]

Originally Posted by B-O-B

G B I doubt that J B weld would work. I don't have an answer for you but sure someone will chime in. Just wanted to mention that I used a paint cup from my touchup spray gun. It has a vented cap & the cap just pushes on for a tight fit. It has the outlet at the bottom of the cup. I just needed to adapt a fitting on my master cly cap & attach a flexible hose from the master cap to the fitting on the cup. Mounted it on the firewall & has worked fine for as far back as I can remember. This is on my 32 hotrod & sorry I do not have a picture.

Really great to hear other folks solution to the same project. And glad to know it works well! I have already searched 'drilling a hole in a glass bottle'. You can see where I'm going with this.

[JimG]

Here are pictures of mine. The car came with it. The cap doesn't seem to be vented. How does it work? Not sure. I never had trouble with it.

[slowforty]

I used plastic caps to fill holes in the firewall, at the auto parts store in many sizes. Disappear with a coat of paint.

[GB SISSON]

Originally Posted by JimG

Here are pictures of mine. The car came with it. The cap doesn't seem to be vented. How does it work? Not sure. I never had trouble with it.

I'm thinking if the cap doesn't have a good gasket under it, that would be enough vent. It seems the vent would be to let air in to displace the fluid forced into the brakes. With a high and firm pedal, not much to displace.

[PeteVS]

Maybe someone could dream up a piece that would fit or be able to tie into the old Ford master cylinder and then have a top that would accept a later "jelly jar" lid with it's very flexible diaphragm. The jelly jar design occurred some time after '63 or so.

[GB SISSON]

Excellent idea Pete! That's a good one. Tell me more about jelly jars and their flexible top. Threaded full size cap, thin steel removable disc as in a mason jar? A disc of black epdm rubber under the ring or the same epdm disc under the steel disc which would have a hole in it. 1/2" diamond holesaw for the bottom feed line. Piece of threaded table lamp tube with 2 epdm washers involved. I had been thinking a clear beer bottle, but the jelly jar lends itself to a diaphram and much easier filling. Come to think of it, even a peanut butter jar with the diaphram and a hole in the lid would work the same. We are going to town this morning and I recall seeing a milwaukee 1/2" diamond hole saw on the rack.

[woodiewagon46]

I have to agree with B-O-B about not using J B Weld. I don't think that the brake fluid will play nice with the J B Weld. I know it doesn't like paint.

[GB SISSON]

I like to research compatibility of various things before ending up with a thick gray sludge plugging up my brake system. Think I will head down to the shop and find a cap off a junk master cyl if I haven't tossed them all out. Should be one on a parts truck.

[PeteVS]

There are "rolling" diaphragms. The trade name is Bellofram. With the convolutions, they can handle a long stroke. It should be possible to make a can the the fully extended Bellofram would just about fill the can below it if all of the fluid was removed. With a full complement of fluid, the Bellofram would be retracted to a flat sort of configuration. As the fluid is removed (as when the brakes are applied or lost) the Bellofram either goes down and back up again or down and not so much up if the system is loosing fluid. In either case, the fluid in the reservoir never gets to contact ambient air.

https://www.belloframdiaphragm.com/a...ted=1650655961

Here's a picture of a master cylinder with a bail type of cover retainer.

[GB SISSON]

Pete, I get what you are saying. My internet is too slow tonight to load the manual in your link though. So if it's a sealed system with a diaphram we don't really get more fluid capacity, just easier to see and fill. Since all my trucks get ambient moisture through a vent already, I'm tempted to skip the diaphram. I will however try again in the morning to download the link you sent. I can see that a sheet of epdm rubber could be a wrong move. Thanks!

[69a]

It is not a "sealed" system. You fill the reservoir about 3/4 full and then insert the concertina style diaphragm, and then fit the cap. The cap must have a vent in the top. The diaphragm keeps the air and the brake fluid apart, but still allows the fluid level to change.

[GB SISSON]

Originally Posted by 69a

It is not a "sealed" system. You fill the reservoir about 3/4 full and then insert the concertina style diaphragm, and then fit the cap. The cap must have a vent in the top. The diaphragm keeps the air and the brake fluid apart, but still allows the fluid level to change.

I guess I consider everything below the diaphram a 'sealed system'. I get the air hole in the cap and it's purpose. The accordian bellows could work well in a half pint mason jar with the snap bail as they have a good wide clamping surface and it's clear for the visual check. Then I'd need a hole in the glass lid. I have learned a lot about remote reservoirs this weekend, including how to spell reservoirs. I feel like I'm involved in a 'think tank' and I enjoy this type of learning. Thanks!