So that's why my brakes suck!

garettb16 · Postby **garettb16** » Sat Aug 23, 2008 1:48 pm

sounds like air in the system too.. id be going to a brake place and getting them to check it over..

brakes are not over-rated.!

CT · Postby CT » Sat Aug 23, 2008 4:39 pm

Hey Caff, flush that garbage dot 5 out of the system and replace with good old dot 4 - castrol super response is all I ever use in the NB8B. For a race style fluid, try Elf HT10 (?) which is what I use in the race car. The NB system does not like dot 5.x in my experience. Then, when you bleed it, try doing it with the ignition switched to on as it opens the ABS valves in the motor unit so that if there is any air, it will pass into the lines. Apart from that, sounds like it's just the fluid that is the issue.

You don't have speedbleeders do you? If so, I've found them not to be as good as everyone reckons as well......they don't always seal on the caliper properly. Another option is to make sure your pads are wearing evenly - I had a seized slider on the road car not long ago too.

rjastra2 · Postby **rjastra2** » Sat Aug 23, 2008 9:30 pm

your ABS cycles when you first start the car after a few moments, correct? I had the hardest time getting a firm pedal with the ABS unit. I started to notice I would bleed the brakes and everything would be great until i started backing out of the driveway and the ABS would cycle. So I threw it back on jackstands, and let the rear wheels spin a tad and hit the brakes, since they lock up instantly the ABS cycles....after I did this a few times and bleed again, I found a huge amount of air and old fluid. Brakes were much improved.

Caffeine · Postby **Caffeine** » Mon Aug 25, 2008 8:08 am

CT wrote:Another option is to make sure your pads are wearing evenly - I had a seized slider on the road car not long ago too.

Bingo!

As Garry hinted at too, Rodd and I took the whole system apart, and 2 seized lower caliper slider pins, and 2 very unevenly worn pads! (8mm vs 3mm on the left front, and 8mm vs 0.5mm on the right front!)

We managed to clean up one of the slider pins and bore, but the other is seized solid. Looks like I'll be ringing round today to source a new frame + slider pins for both sides, plus new pads.

The rubber boots both has small nicks in them, which obviously let the grease out and the crap in. Funny part is the slider pins and pad wear were ok at my recent dodgy day! :shock:

P.S. I find the advances to be a very good road pad, and I had no troubles with them at the track either.

Caffeine · Postby **Caffeine** » Mon Aug 25, 2008 10:31 am

MX5Plus and MX5Mania both don't have the NB8B brakes available (damn all you NA6 owners upgrading

)

Looks like Mazda may be my best bet, probably hideously expensive though... :evil:

Charlie Brown · Postby **Charlie Brown** » Mon Aug 25, 2008 11:12 am

Caff, take the old calliper down to your friendly local brake repairer and get them to free the frozen one up. They can then grease and refurb them if required.
Far cheaper than replacing them.

Caffeine · Postby **Caffeine** » Mon Aug 25, 2008 11:18 am

Charlie Brown wrote:Caff, take the old calliper down to your friendly local brake repairer and get them to free the frozen one up. They can then grease and refurb them if required.
Far cheaper than replacing them.

I thought of that, but it's very well stuck at the moment. The slider pin that we did manage to free was pitted and scored too, so I'll need new ones of them at a minimum.

Caffeine · Postby **Caffeine** » Mon Aug 25, 2008 11:27 am

Caffeine wrote:Looks like Mazda may be my best bet, probably hideously expensive though...

Yep, $747.40 a side! :shock:

That's for a full caliper assembly, as the service guy claimed the parts weren't available separately.

Strangely enough, I called the same service centre up on saturday and asked about the slider pins (before we'd taken the second side off and found the completely seized one) and I was quoted $17.50. So the parts ARE available individually, just that this guy couldn't find them on the system I guess.

Caffeine · Postby **Caffeine** » Mon Aug 25, 2008 11:54 am

Helps to phone around, called up another dealer (incidentally the one i bought the car from

) and the parts guy there found all the individual parts I was after (driver and passenger side caliper mounting supports, 2 each of the upper and lower slider pins, and 4 slider pin rubber boots) for $436

and they'll have them for me tomorrow afternoon, so I can put everything back together on Wednesday!

Hurrah, just need to get some brake pads and I'll be all set!

wun911 · Postby **wun911** » Mon Aug 25, 2008 1:00 pm

Can you just replace the pins?
http://ww2.mx5parts.co.uk/product_info. ... cts_id/897

Do you notice that one of the pins has a grove (I think to hold the grease) and the other one doesnt? Are both the pins the same size and lenght or what?

Im tempted to replace them all with groves has anyone done this?

Caffeine · Postby **Caffeine** » Mon Aug 25, 2008 1:46 pm

wun911 wrote:Can you just replace the pins?
http://ww2.mx5parts.co.uk/product_info. ... cts_id/897

Do you notice that one of the pins has a grove (I think to hold the grease) and the other one doesnt? Are both the pins the same size and lenght or what?

Im tempted to replace them all with groves has anyone done this?

Well I would just replace the pins, except one of them is frozen solid in the frame, and I can't get it out!

The upper pins have a groove (well 3 flat sides) for grease.

The upper and lower pins are a different shape, so aren't interchangeable.

The breakdown of parts cost is as follows:

Mounting Frame (#9 on the attached picture) : $154 per side (2 required)
Slider Pin - Upper & lower (#2 on the attached picture) : $19 each (1 upper and 1 lower per side, 4 in total)
Slider Pin Boot (shown in circular breakout on attached picture) : $13 each (4 required)

brakes.PNG

Caffeine · Postby **Caffeine** » Mon Aug 25, 2008 3:04 pm

Phew, Mania will have some hawk HP+ pads for me in the next couple of day too, $195 for the front set isn't bad

Garry · Postby **Garry** » Mon Aug 25, 2008 3:28 pm

Caffeinne,

Are the rubber sleeves on the bottom slider pins available as a seperate part? One of mine is warn a bit.

Wun911,

The slider pins on the NB8B are different to the ones on my NA8, but the NA8 ones might be the same as the NB8A ones.

Caffeine · Postby **Caffeine** » Mon Aug 25, 2008 3:55 pm

Garry wrote:Caffeinne,

Are the rubber sleeves on the bottom slider pins available as a seperate part? One of mine is warn a bit.

Yep, the boots are $13 each apparently. I don't really need to replace the top two slider pins and boots as they look fine, but I thought I might as well freshen the whole lot up.

I'll get the part number when I pick them up, something like D25D33xxxx from memory...

rjastra2 wrote:your ABS cycles when you first start the car after a few moments, correct? I had the hardest time getting a firm pedal with the ABS unit. I started to notice I would bleed the brakes and everything would be great until i started backing out of the driveway and the ABS would cycle. So I threw it back on jackstands, and let the rear wheels spin a tad and hit the brakes, since they lock up instantly the ABS cycles....after I did this a few times and bleed again, I found a huge amount of air and old fluid. Brakes were much improved.

Interesting! I'll do that in addition to CT's suggestion. It should help.

We did bleed the ABS block, and a bit of air came out one of the lines, but nothing spectacular.

CT · Postby CT » Mon Aug 25, 2008 10:22 pm

Good to hear you've found the issue Caff - don't forget to drain out that 5.1 stuff. I've been down that track before too and it's not the best for our babies. I think the manual recommends DOT 3 or 4 from memory too.