Pedal box and fluid reservoirs

[Dr.Jeff]

In planning a complete hydraulic system overhaul (new reservoirs, hoses, masters, slave, calipers, flex lines, and related ancillary devices), a couple questions have come to mind:

1) If replacing the dual-chamber/single vessel brake fluid reservoir with two clutch fluid reservoirs, doesn't that mess up the size of the hose to tank fittings? Because I believe the clutch reservoirs use 5mm hose and the brake master cylinder uses 7mm hose.

2) I seem to recall a good Xweb tutorial on rebuilding the pedal box, but now I can't find it. I thought I had it saved on my hard-drive yet I don't see it. And searching the forum brought up many discussions that included the various terms but not what I was looking for. Has my memory failed (again) or did I just miss it when searching?

3) I'm sure will be added soon.

By the way, considering the restoration of the hydraulic system seems to be one of the least favorite jobs on the X, and given the multitude of discussions that have taken place surrounding the various aspects of this job, I am surprised there aren't more Wiki articles on it. I've stumbled on a number of good tips, techniques, tricks, and golden tid-bits...all scattered throughout dozens of threads, none of which is in the Wiki. If I had realized this when I started my search I would have been saving them to compile into one article. Perhaps someone else has done so???

 

[Rodger]

In planning a complete hydraulic system overhaul (new reservoirs, hoses, masters, slave, calipers, flex lines, and related ancillary devices), a couple questions have come to mind:

1) If replacing the dual-chamber/single vessel brake fluid reservoir with two clutch fluid reservoirs, doesn't that mess up the size of the hose to tank fittings? Because I believe the clutch reservoirs use 5mm hose and the brake master cylinder uses 7mm hose.

2) I seem to recall a good Xweb tutorial on rebuilding the pedal box, but now I can't find it. I thought I had it saved on my hard-drive yet I don't see it. And searching the forum brought up many discussions that included the various terms but not what I was looking for. Has my memory failed (again) or did I just miss it when searching?

3) I'm sure will be added soon.

By the way, considering the restoration of the hydraulic system seems to be one of the least favorite jobs on the X, and given the multitude of discussions that have taken place surrounding the various aspects of this job, I am surprised there aren't more Wiki articles on it. I've stumbled on a number of good tips, techniques, tricks, and golden tid-bits...all scattered throughout dozens of threads, none of which is in the Wiki. If I had realized this when I started my search I would have been saving them to compile into one article. Perhaps someone else has done so???

Here is Bernice's thread on her pedal box restore. Inspirational. https://xwebforums.com/forum/index.php?threads/74-pedal-box-project.25800
As far as using two clutch reservoirs, yes the outlets are 5mm instead of 7. You can put 5mm inlets on the brake master and use 5mm hose for the runs. I am pretty sure that is the way the early X's were.

 

[Dr.Jeff]

You can put 5mm inlets on the brake master and use 5mm hose for the runs.

Easy! Thanks Roger.

And thanks for the link, it is a good example of what I referred to when I said the brake portion of the Wiki needs additional material.

However I was trying to find something that focuses more on things like replacing the plastic pivot bushings and similar stock refurbishment, and pertained to the later style box (there are some differences compared to the one in this link). I could swear I remember a nice write-up on it...anyone?

But again, thanks.

 

[Dr.Jeff]

Regarding the brake-fluid reservoirs' replacement, another thought I've considered is using a single reservoir to feed all three lines. The concept would be to mount one reservoir (say the clutch type) in the vent trough/box with one feed hose going to the opening just above the steering column at the firewall (bulkhead). At that point it connects to a 3-way split or manifold (actually 4-way, 1-in and 3-out), to feed the two masters. Given the very small volume of fluid that is drawn in with each stroke of either master, the single feed would be more than sufficient. Naturally this does away with the redundant and isolated reservoirs (done by the factory for safety), so if the reservoir failed you could loose the supply to all three. But frankly I'm not concerned with that; it has never happened to me or anyone I know over the past 50 years. Plus I regularly check and service my vehicles so I'd likely notice a problem before it became critical, so not a huge risk (again, in my opinion). What is especially nice about this set-up is there might be enough room on the driver's side to mount the single reservoir (the smaller clutch style), thus shortening the total supply hose length for all three feeds to only a few inches.
Just a thought.

 

[JDExSquid]

I just completed a overhaul on my hydraulic system, mostly due to rusty masters and my pedal box had seized up due to the leaking brake fluid washing away the grease and causing rust where the pedal meets the plastic bushing. It was a mess. All parts were replaced with MWB parts. His brake master cylinder comes with 5mm fittings in the bag, so it's no problem to use your two reservoirs. Bleeding the clutch was easy: From an empty system, I filled the clutch reservoir 3/4 full then pulled a vacuum at the top with a vacuum pump and my hand covering the top to make a seal. I guess it pulled the air out of the lines because when I released the vacuum, I watched the fluid level go WAY down on the clutch reservoir. From there I simply vacuum bled from the slave cylinder and it was done. Ten minutes tops. The brakes were a lot bigger challenge because the fronts simply would not bleed. After research on Xweb I followed another members method and pressure bled from the calipers to the reservoir. That worked for me.

 

[lookforjoe]

What year is your X? Mine ('87) had 130K on it when I took mine apart - there was nothing to remark on in terms of hardware wear issues relating to the pedals or pivots. I switched to the single reservoir setup (using three, clutch & one for each brake circuit) & moved them into the trough, having them in the Frunk seemed a bad idea, as the fluid leaking/spillage definitely would cause issues with the battery tray life. At least fluid can potentially drain/ be flushed where there are now. It did not occur to me that there was a difference in nipple sizing with these - that would explain the slight weepage I had with the original hose, before I put sturdier clamps on the hose. It's all good with the hose I bought from the TractorSupply recommended by Jeff VanDyke (can't recall the brand)

 

[carl]

I never looked into it but many sport bikes have the reservoirs for the brakes and hydraulic clutches as clear plastic containers that sit above the brake and clutch levers. They might be just the ticket for Xs.

 

[Dr.Jeff]

I never looked into it but many sport bikes have the reservoirs for the brakes and hydraulic clutches as clear plastic containers that sit above the brake and clutch levers. They might be just the ticket for Xs.

I explored the idea of motorcycle reservoirs. I also build bikes so I had access to them to play with. Even the largest ones are still very small for automotive use...less than a quarter of the size of the X's clutch reservoir. I was hoping they might fit directly on top of the master cylinder to eliminate the long feed hoses all together. But not enough room down there, even for these tiny reservoirs. Plus it would be impossible to top them up.

I'm still contemplating the idea of using just one reservoir for all three feeds and locating it on the driver's side to significantly reduce the feed hose length. Even one clutch reservoir is larger than three bike reservoirs, but it might be pushing the limits of being too small. Would need to keep an eye on it to make sure the level doesn't drop.

& moved them into the trough, having them in the Frunk seemed a bad idea

Hes, where exactly where the reservoirs located on yours originally? I've only seen them in the trough (but never had a late year model to compare with).

 

[lookforjoe]

Hes, where exactly where the reservoirs located on yours originally? I've only seen them in the trough (but never had a late year model to compare with).

This is where the original single reserviour was mounted (on a bracket) - the two hoses came through the trough in the holes shown:

EDIT - here's a pic from when I first got the car:

 

[kmead]

This is where the original single reserviour was mounted (on a bracket) - the two hoses came through the trough in the holes shown:

EDIT - here's a pic from when I first got the car:

So this is interesting to me. I have always hated the washer tank as it is way too big and takes up too much room. I don't see any actual reason that the reservoirs couldn't be in the compartment as they effectively don't outgas and I have never seen one explode (aside from being impacted by a object in the compartment). Getting them out of the weather might improve their longevity and reduce the water infusion into the hydroscopic brake fluid.

Putting the reservoirs on the opposite side of the space from where this image shows and then having the hoses go down the existing opening nearly directly would seem like a better situation.

The draining of any spilled fluid is a good feature of the existing position that I have used to my advantage in the past.

I will say that on my '87 the hoses collected enough detritus and held it in one place for long enough that the tray in that area actually rusted through so that water could fall into and on the fuse box. Not good (one of the two places that have rust on the car, the other is in the passenger footwell near the intended drain which I think was clogged, I wonder if the water came in from the cowl and collected there but I digress).

As long as the units were out of the line of fire from the top being placed and removed it would seem the reservoirs could be placed next to the hood anti intrusion mushroom bracket and have the hoses nearly go directly to the masters. I will look at it a bit with the BMW reservoir I bought from Jeff Stich.

 

[Jeff Stich]

This is where the original single reserviour was mounted (on a bracket) - the two hoses came through the trough in the holes shown:
EDIT - here's a pic from when I first got the car:

When you say "original", are you merely referring to where it was located when you got the car? Because that's not the OEM location for the large single reservoir - it's normally mounted in the cowl next to the clutch reservoir (right where your tandem reservoirs are mounted).

 

[Dr.Jeff]

Putting the reservoirs on the opposite side of the space from where this image shows and then having the hoses go down the existing opening nearly directly would seem like a better situation.

Because that's not the OEM location for the large single reservoir - it's normally mounted in the cowl next to the clutch reservoir (right where your tandem reservoirs are mounted).

As Jeff states, I'd never known any of the reservoirs to be in the frunk rather than in the vent-trough (cowl). But as Karl said, the idea of mounting the reservoirs on the other (driver's) side with significantly shorter feed hoses would be a real advantage (in my opinion). Frankly I can't understand why Fiat configured it with those incredibly long hoses. Similar to Karl's experience, mine not only started (surface) rusting the sheet metal under them but the exterior of the hoses themselves has severely deteriorated from the accumulation of crud around them. And as Karl also stated, not having the reservoirs directly under the air vent grills may help reduce water exposure.
With regard to the windshield washer bottle. Yes, it is WAY too big and taking up valuable space in the frunk. On the earlier models the tank is a small bag located in the left headlight well. Although I intend to eliminate it on mine anyway (I've never utilized windshield washers on any of my vehicles...but that's another story).

 

[JimD]

I looked into this 87X shell at one time thinking about making an AutoX. Someone reworked the whole set up in the frunk with non-Fiat components.

 

[Dr.Jeff]

That would be a good option for a track car.
Kind of amazing how distorted that left strut top mount is.

 

[lookforjoe]

Putting the reservoirs on the opposite side of the space from where this image shows and then having the hoses go down the existing opening nearly directly would seem like a better situation.
.

This would make perfect sense, drastically reduce fluid travel & debris in the trough because the hoses lay in there. I wonder why they didn't do that in the first place....

 

[lookforjoe]

When you say "original", are you merely referring to where it was located when you got the car? Because that's not the OEM location for the large single reservoir - it's normally mounted in the cowl next to the clutch reservoir (right where your tandem reservoirs are mounted).

Yes, I stand corrected, I should have clarified my statement. That was how it was situated when I got the car. Presumably the original had been replaced with aftermarket at some point in its past. With the mount bracket, it looked professional, albeit hokey due to the hose routing through the trough without any grommets to protect the hoses as in evidence on the left side trough.

 

[carl]

I spent a whole year trying to come up with a better set up for the reservoirs with little luck. The stock reservoir was busted so I was trying to use a 124 version which unfortunately has downward pointed spigots so it wouldn't fit in the cowl (not enough vertical clearance with the hood. The 124 containers seem to be made of much better quality plastic as I have never seen one go bad. I then tried to mount it on the front trunk wall but the brake MC sits high enough that it was a puzzle to get the container high enough to have a clear downward flow from the container to the MC yet clear the hood when it was closed. Even the stock container has a mostly horizontal run of the supply hose. I gave up and got the Stich conversion!

 

[Dr.Jeff]

downward pointed spigots

I can see where the downward nipples would be a problem with getting it positioned high enough. However with side exit nipples I think they could be located on the frunk wall (on the driver's side, directly in front of the hose-passageway / tunnel) high enough to allow full gravity feed to the masters and still clear the hood, etc. However it will require cutting holes for the hoses to pass through. The other question is to make sure this will also clear the top when stored. But I like the idea of eliminating those super long hose leads.

 

[lookforjoe]

I can see where the downward nipples would be a problem with getting it positioned high enough. However with side exit nipples I think they could be located on the frunk wall (on the driver's side, directly in front of the hose-passageway / tunnel) high enough to allow full gravity feed to the masters and still clear the hood, etc. However it will require cutting holes for the hoses to pass through. The other question is to make sure this will also clear the top when stored. But I like the idea of eliminating those super long hose leads.

I took a pic of the space available with the targa stowed....

...Pretty tight quarters for a reservoir, ensuring it's height is at a minimum no lower than if it were in the trough. Holes through the wall aren't really a big deal, just need to properly grommet them.

 

[Dr.Jeff]

Nice photo Hess.
Maybe mount the reservoirs just to the left (driver's) side of the access port (where the wire cable runs through in the pic), toward where those relays are. With the nipples aiming toward the passenger side. Then curve the hoses 90 degrees through the fire wall. Not sure if that is a clear description, but my point is you might be able to locate the reservoirs in that nook off to the side of the stowed top.