Relocate MZ5 Brake Fluid Reservoir?

phunky.buddha

Booga Booga?
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DFW TX
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No mo MZ5 want MX5
Has anyone tried to move the brake fluid reservoir? It's right on top of the driver's side strut tower, so any camber plate installed in that location would be blocked. I imagine it wouldn't be a big deal- the reservoir is just a holding tank for more fluid so the master cylinder doesn't run out as the pads get worn, but I'm trying to firm up a few things:

1. If I move the reservoir to the center of the engine bay opposite the battery box, is heat going to be an issue since it'll be over the exhaust manifold? I guess a heat shield around/under the reservoir could do the trick here.

2. If I move it to the other side of the engine bay and hang it just inside the passenger strut tower or near the windshield washer fluid reservoir, is the extra long hose run going to be an issue? I'm thinking probably not as long as the hose always runs on a downward slope and always has fluid in it.

3. Is this an issue on the 3? I don't remember from the last time I looked inside a 3's engine bay.

4. Another location is possibly the vent area for the battery- is there really any reason why we have a monster intake/vent for the battery box like that? Is there something weird about the 3/5's battery that needs positive flow and can't just sit open air?

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The solution I picked was to mount it right on top of the battery box cover. This brings it back to what the Mazda engineers probably wanted to prevent- having the lid sit under the cowl and be difficult to access. I can still remove the lid, but it'll take a funnel to pour in more fluid. No big deal for me- nobody but me will touch my brakes, so I can deal with the weird location. So, quick facts:

1. New location puts the least amount of additional stress on the hose as possible- the reservoir is placed so that just one bend on the hose gets straightened out a bit.
2. Battery box cover is still removable.
3. One option was to use the battery box cover area as a temp mount and just move the reservoir there before going for an alignment, but nobody is going to mess with the battery or the fluid but me, so I'll just leave it here.
4. Reservoir stays at pretty much the same elevation as before, so the fluid still runs "downhill" through the line to the master cylinder.

Before:
mz5_brk_res_move_m_01.jpg


After:
mz5_brk_res_move_m_14.jpg


More detail below...
 
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dude.. if its to access your camber plate your point is moot without modifiying the strut tower area...

the hole is truly not big enough to get a screw driver in there or any tool to adjust them camber plates.. i would know man.. along with quite a few others here on coils


you would have to modify the structural integrity to be able to access them..

look@ your passenger side mount see how small that hole is?? you will have to cut that out and enlarge it... the minimum amount to cut would be where it kinda bubbles up...
 
dude.. if its to access your camber plate your point is moot without modifiying the strut tower area...

the hole is truly not big enough to get a screw driver in there or any tool to adjust them camber plates.. i would know man.. along with quite a few others here on coils


you would have to modify the structural integrity to be able to access them..

look@ your passenger side mount see how small that hole is?? you will have to cut that out and enlarge it... the minimum amount to cut would be where it kinda bubbles up...
Can you post a pic for a visual on how you modified the top of the strut tower or did you pre-adjust the camber and mount everything? How did you know what to set the camber too? Also, did you go with factory alignment sepcs or using something different?
 
i pre adjusted before installing with it set to maximum positive.. this was negated as soon i dropped the coils to the lowest possible making them .1 degree negative in front, every car is different, get a lifetime alignment and then go do your coils..

bc's extreme drop still are not that low.. im sure i can get some swift springs and revalve the fronts so i can go lower.. im only 3.5 inches from the ground now (actual pinch welds.. im trying to do 2 inches from it..
 
dude.. if its to access your camber plate your point is moot without modifiying the strut tower area...

the hole is truly not big enough to get a screw driver in there or any tool to adjust them camber plates.. i would know man.. along with quite a few others here on coils

you would have to modify the structural integrity to be able to access them..

look@ your passenger side mount see how small that hole is?? you will have to cut that out and enlarge it... the minimum amount to cut would be where it kinda bubbles up...

That was my intention... I was going to open the hole up to the size of the ridiculously thick steel plate that sits on top of it. I don't know if there's a flat metal plate on top of the 3's strut towers, but there is on the 5- cutting everything out inside the hole wouldn't compromise structural integrity at all. I'm not worried about cutting the hole, just seeing what people might have done with moving the fluid reservoir.
 
i pre adjusted before installing with it set to maximum positive.. this was negated as soon i dropped the coils to the lowest possible making them .1 degree negative in front, every car is different, get a lifetime alignment and then go do your coils..

bc's extreme drop still are not that low.. im sure i can get some swift springs and revalve the fronts so i can go lower.. im only 3.5 inches from the ground now (actual pinch welds.. im trying to do 2 inches from it..
So you have to remove the whole suspension to adjust the camber plate? Would alignment shops do that for every adjustment?


Sounds like you are more interested in slamming it as low as it can go and don't care for suspension tuning? Did you consider cutting a coil or two from the BC kit spring? That won't make up 1.5" difference but it’s a cheap start. Maybe you can cut more coils and use helper or tender springs to align them (just a thought)?

Care to post a pic of your current stance?
 
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@ phunky - Just an FYI but you prob already know this.

You have a manual, right? The Mz5's clutch fluid reservoir runs off the brake's reservoir, it is not two separate systems. Looking at the firewall, it runs down and to the left of the brake reservoir, both are filled here. This means trying to place it on the far right side of the firewall will be difficult unless you reposition the clutch reservoir too. The middle looks like a better option but as you stated, that is right above the mani and I would imagine there's a lot of heat in TX summers.
 
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I didn't know that the clutch fluid ran from the same line- it looked to me like it went straight from that reservoir to the master cylinder reservoir. I'll look back at the line again.

Looking at the MZ3 and MS3, the reservoir is dead center, so heat probably isn't a problem. The 5's cowl just sticks out farther, so it covers up (I assume) where the reservoir would be located on the 3.

I figured out an easy $5 solution that doesn't even involve disconnecting the factory line though. Pictures as soon as I button the car up.
 
So, this is how to relocate your Mazda 5 brake fluid reservoir for less than $10 so you can access your driver's side strut tower/mount.

This is what it looks like stock- the mount is behind the reservoir.
mz5_brk_res_move_m_01.jpg


Removing the reservoir shows where all the new hardware will eventually sit.
mz5_brk_res_move_m_02.jpg


Mocking up the location I want- I just drew through the mounting hole with a pencil.
mz5_brk_res_move_m_03.jpg


Battery cover drilling: 2.5 inches off top molded-in line
mz5_brk_res_move_m_04.jpg


A little under an inch going up
mz5_brk_res_move_m_05.jpg


Distance between mounting studs = 11cm, so make sure you drill the second hole accordingly
mz5_brk_res_move_m_06.jpg


Parts you need (forget the hex nuts, don't necessarily need them) to move your reservoir
mz5_brk_res_move_m_07.jpg


Holes drilled:
mz5_brk_res_move_m_08.jpg


Fastener stackup; plastic parts go between the washers, bolt starts from inside the battery cover
mz5_brk_res_move_m_09.jpg


Stackup on top- battery cover, washer, lock nut, washer x2, regular nut (can reuse car's nuts)
mz5_brk_res_move_m_10.jpg


What it looks like with only the reservoir moved around.
mz5_brk_res_move_m_11.jpg


mz5_brk_res_move_m_12.jpg


Showing that the fluid line still runs downhill.
mz5_brk_res_move_m_13.jpg


Even more room after rerouting the ground cable.
mz5_brk_res_move_m_14.jpg


Alternate front view.
mz5_brk_res_move_m_15.jpg
 
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Could you just temporarily move the reservoir, make the necessary cuts in the tower for the camber plate, get the car aligned to your sepc, and put the reservoir back where it was originally? Is there enough clearance for the knob to adjust the damper?
 
Yeah, I could- the original plan was to just mount the bolts there to place the reservoir while the alignment was getting trimmed in, then move it back. I'll probably still move it back to the stock position once I get my alignment where I want it, but for now it's functional in the new location too. It's 100% reversible in under 2 minutes with the exception of the new holes in the battery cover- so I now just have two options on mounting location.

I don't remember if there's enough room to get to the adjustment knob with the reservoir in place. There probably is, but it's a tight fit and I have big hands, so I'd want to do all damper adjustments with the reservoir in the new location.
 
Great write up and thanks for taking the extra time to get pics.

Only question I have is: Would you still be able to have a strut tower brace installed?
 
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Great write up and thanks for taking the extra time to get pics.

Only question I have is: Would you still be able to have a strut tower brace installed?

Welcome. I always take pics too. :D

I don't know that you would still be able to have a strut tower brace, but the strut towers are so close to the firewall- I don't know that a brace in that spot would make much of a difference at all.
 
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