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You might want to change that brake fluid a bit sooner.

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Old 04-15-2010 | 05:29 PM
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good brown gravy!
Old 04-15-2010 | 05:33 PM
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Where does that part go? What's its function?

Mazda cars do tend to be a bit pricey when it comes to parts. OTOH, the '94 Miata I used to have was quite possibly the most reliable vehicle I've ever seen.
Old 04-15-2010 | 07:33 PM
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I met a guy in Saudi who bought an early 80s Rolls cheaply - diplomat being sent home had to dispose of it urgently. Full service hsitory, low miles etc etc. Couple of leaks in the chassis lube system, no big deal. After 250 highway miles, the tyres started to feel out of balance - on isnpection there were chunks of ruubber falling off - the tyres were ORIGINAL fitment from NEW!
jp 83 Euro S AT 52k
Old 04-15-2010 | 08:40 PM
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After buying my 928 I checked the brake fluid and it was green. I read something about the brake line being copper lined and possible mineral oil. Flushed the system and used clear fluid but a year later it is showing a green tint.
Old 04-15-2010 | 09:10 PM
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Getting back to the 928 (this WAS a 928 support board when I logged on...), folks should pay close attention. Hydraulic systems will pretty much last forever unless they run dry or get contaminated with something. Moisture in the air quickly becomes moisture in the brake fluid. The fluid is hygroscopic, which means it will readily absorb moisture. The only way to keep the moisture levels low is to replace the old wet fluid with new fluid on a regular basis. How regular? Porsche recommends every two years. IMHO, that is a minimum requirement; more often is better, especially if you live in a humid climate. A 'humid climate' is any place that isn't the desert.

How easy is it to flush the fluid? There's a handy Motiv tool made just for this, marketed by our favorite parts vendors here. Filll the little tank with new fluid, scrw the cap on where the brake master cylinder reservoir cap is now. Pump up the little tool. Now go to each wheel, and attach a small hose to each brake bleeder nipple in succession. Open the bleeder with a small wrench, and let fluid flow through until it comes out clean and with no bubbles. Move to the next bleeder and repeat, until all the old fluid is out and only new clean dry fluid is in the system. For non-race cars, the commonly-available Castrol GTX LMA fluid is DOT4 rated and more than up to the task. You can spend more on colored fluids like ATE blue or gold, or on one of the big-ticket race fluid like the Motul 600. For us mere mortals, a couple liters of the GTX LMA fluid will be plenty, and the cost won't break the bank. It's just too easy a task to let go.

We do somewhat-regular brake fluid flush clinics here at the ranch on the hill. Mine is due for its annual work in June, so sometime between now and then we'll probably have a clinic so that other local owners can see how easy it is, use the flush tool, and have a support team of coaches to tease them. You get to look at brake pads while the wheels are off too, eat bratwurst off the grill and drink whatever bevs you choose (...to bring along...). Thinking mid-June right now, since my travel schedule is packed between now and then. That will give you time to stop by the local parts place and grab a couple bottles of fluid too.

My garage floor is due for resealing right about then. Since spilled bake fluid trashes the sealer on the epoxy, Mid-June will be the perfect time.
Old 04-15-2010 | 09:18 PM
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I change my fluid every year a couple weeks before SITM, doesn't cost much or take long and being on a regular schedule will hopefully ensure I will never again boil my brake fluid going down NC80
Old 04-15-2010 | 09:36 PM
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Originally Posted by JHowell37
Where does that part go? What's its function?

Mazda cars do tend to be a bit pricey when it comes to parts. OTOH, the '94 Miata I used to have was quite possibly the most reliable vehicle I've ever seen.
It is the bottom half of one of two accumulators for the brake system, this hooks up to the valves that put pressure to 2 or 4 of the six calipers.
The system is split into two parts, system one and system two.

The purpose is store pressure from one of the two engine driven pumps for brake pressure in case the engine stops running, with out these working you will have zero brakes if the engine stops running, not good.

The brake system is 100% different than anything most mechanics have ever seen.
Old 04-15-2010 | 09:42 PM
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Originally Posted by rixter
I change my fluid every year a couple weeks before SITM, doesn't cost much or take long and being on a regular schedule will hopefully ensure I will never again boil my brake fluid going down NC80
Every year works, on any car.
Old 04-15-2010 | 10:04 PM
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I know its OT, but...
I once worked on the brakes on an old Rolls . This was ALONG TIME before ABS was around, but it had that feature. The brake boosting was done by fitting a right angle driven shaft out the rear of the gearbox, which had a spinning disc with a clutch lining face. When the pedal was pushed, a matching discmoved towards the spinning one on a coarse screw thread- this helped to pull the pedal down and reduce foot effort. The benefit of this was that as soon as the back wheels locked, you lost boost, and the brakes oscillated on/off if you achieved lockup. Very simple, adjustment was simple - take up wear in the linings as required.
The other interesting part was that despite all the underside covers that had tto be removed, they were designed so that nothing could go back in the wrong place....really very easy to work on.
jp 83 Euro S AT 52k
Old 04-15-2010 | 10:13 PM
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How old, what model was that?
Sounds neat.

Originally Posted by jpitman2
I know its OT, but...
I once worked on the brakes on an old Rolls . This was ALONG TIME before ABS was around, but it had that feature. The brake boosting was done by fitting a right angle driven shaft out the rear of the gearbox, which had a spinning disc with a clutch lining face. When the pedal was pushed, a matching discmoved towards the spinning one on a coarse screw thread- this helped to pull the pedal down and reduce foot effort. The benefit of this was that as soon as the back wheels locked, you lost boost, and the brakes oscillated on/off if you achieved lockup. Very simple, adjustment was simple - take up wear in the linings as required.
The other interesting part was that despite all the underside covers that had tto be removed, they were designed so that nothing could go back in the wrong place....really very easy to work on.
jp 83 Euro S AT 52k
Old 04-15-2010 | 10:21 PM
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Well, best I can recall it was a late 50s, early 60s model. Certainly before they decided that disc brakes might be up to their demands. Large-ish drums (11 or 12" dia x 3" wide shoes) - self adjusting, 2 trailing shoes, practically unfadeable, smooth as glass, but needed lots of boost. I had an old Rover with same type of fronts, never had any issues with them.
jp 83 Euro S AT 52k
Old 04-15-2010 | 10:27 PM
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cool, sounds neat.
Old 04-16-2010 | 12:19 AM
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Its funny how things come up, one of my wife's friends has an old Rolls, he asked me a few weeks a go if I would look at his brakes, I said sure, after reading all of the above that's all I'll be doing, looking at them.
Old 04-16-2010 | 12:24 AM
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If you have never worked on drum brakes, it might be a bit daunting at first sight, but its very easy to explain how they work (assuming same as I spoke of above), and R&R is very straightforward.
As far as accumulators and pumps etc, not going there....
jp 83 Euro S AT 52k
Old 04-16-2010 | 01:46 AM
  #30  
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Originally Posted by blown 87
Actually I do not find them out of line for the price of the car when it was new.

The ones that get me for parts price is anything made by Mazda, now that stuff is
Yep. My wife's Mazda 626 wagon was hell on wheels for parts prices.
Fortunately, the car was also sold here as a Ford - often the EXACT same part could be bought at the Ford dealer over the road for less than 20% of Mazda's price.

Case in point - exhaust downpipe (manifold to cat, two feet of mild steel pipe, with a bend and two flanges) - Mazda $837, Ford $154, Custom made $87 including new bolts.


Quick Reply: You might want to change that brake fluid a bit sooner.



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