Front and rear caliper rebuild part numbers?

deags · Postby **deags** » Mon Jun 12, 2017 10:23 pm

Hi,

I am looking at rebuilding a full set of '99 NB brake calipers.

B2YD-33-26Z appears to be the kit for the front calipers, but I haven't been able to confirm that they are also suitable for the rear, and if they are not, are rebuild kits available for the rear?

Any other advice regarding rebuilding and fitting these brakes to an NA6 would be appreciated too.

Cheers

93_Clubman · Postby **93_Clubman** » Tue Jun 13, 2017 11:09 am

Think that kit does just fronts: http://www.mx5cartalk.com/forum/viewtop ... 0&p=909354
But it sounds like there might be a kit that does both: viewtopic.php?f=30&t=74569
Looked earlier this year & ebay also had some kits from UK (US ebay had further kits):
https://www.ebay.com.au/sch/i.html?_fro ... sacat=9800

RS2000 · Postby **RS2000** » Tue Jun 13, 2017 12:26 pm

The kits won't be the same both ends, because of different piston sizes.
Any local brake shop or brake parts supplier will supply kits

93_Clubman · Postby **93_Clubman** » Wed Jun 14, 2017 10:58 am

Yeah, similarly would have thought local brake place could supply a kit, but a forumite recently seemed to have some difficulty with this: http://www.mx5cartalk.com/forum/viewtop ... 0&p=909354

RS2000 · Postby **RS2000** » Wed Jun 14, 2017 4:32 pm

You'll have no problem getting them if you accept aftermarket from MCX or Protex - just as good as seals with genuine mazda on the packet anyway.
MX5parts UK show both front & rear seal kits also.

deags · Postby **deags** » Fri Jun 30, 2017 2:16 pm

Thanks everyone for all your input.

The slider pins on the front were not moving well so I'm diassembling and rebuilding them and leaving the rears to minimise cost.

Has anyone rebuilt front NB8A calipers before? These dust boots won't come off and I'm hesitant to keep yanking on them because I don't want to end up with a bit of rubber stuck down there. The other ones all came off easily but these ones are different...
https://i.imgur.com/eyB6res.jpg

While I'm at it can someone confirm that the bolts that mount the calipers to the car are the same on NA6 and NB8A calipers? I don't have all the bolts for the NB8A ones.

Snowmotion · Postby **Snowmotion** » Fri Jun 30, 2017 2:49 pm

I could not get the dust boots off either so just left the old ones on.

deags · Postby **deags** » Fri Jun 30, 2017 3:08 pm

That's my inclination but it makes getting all the old grease out of the hole that much harder - and I have shiny new ones to put on!

93_Clubman · Postby **93_Clubman** » Fri Jun 30, 2017 5:01 pm

deags wrote:can someone confirm that the bolts that mount the calipers to the car are the same on NA6 and NB8A calipers?

Can't confirm, but there were a lot of shared parts, so think they are the same.

deags · Postby **deags** » Fri Jun 30, 2017 6:20 pm

Thanks.

Bigger problem - I've got the squate cut seals in no issue, but the piston dust boots don't fit. I tried for about 30mins to get one of the buggers on, it's a bit too big.

Has anyone got any experience with the Febest rebuild kits? I hope I am just bad at this and it can be done...

RS2000 · Postby **RS2000** » Sat Jul 01, 2017 11:42 pm

deags wrote:Thanks everyone for all your input.

The slider pins on the front were not moving well so I'm diassembling and rebuilding them and leaving the rears to minimise cost.

Has anyone rebuilt front NB8A calipers before? These dust boots won't come off and I'm hesitant to keep yanking on them because I don't want to end up with a bit of rubber stuck down there. The other ones all came off easily but these ones are different...
https://i.imgur.com/eyB6res.jpg

The pin boots are one piece. Cut off the blind 'knob' end (other end to that shown on photo). You have to lube the new boot to get the knob end right thru' the caliper hole.
The piston boots are very hard to fit. Keep trying

RS2000 · Postby **RS2000** » Sun Jul 02, 2017 10:53 am

RS2000 wrote:
deags wrote:Thanks everyone for all your input.

The slider pins on the front were not moving well so I'm diassembling and rebuilding them and leaving the rears to minimise cost.

Has anyone rebuilt front NB8A calipers before? These dust boots won't come off and I'm hesitant to keep yanking on them because I don't want to end up with a bit of rubber stuck down there. The other ones all came off easily but these ones are different...
https://i.imgur.com/eyB6res.jpg

The pin boots are one piece. Cut off the blind 'knob' end (other end to that shown on photo). You have to lube the outside of the new boot to get the knob end right thru' the caliper bracket hole.
The piston boots are very hard to fit. Keep trying

deags · Postby **deags** » Sun Jul 09, 2017 2:53 pm

RS2000 wrote:
RS2000 wrote:
deags wrote:Thanks everyone for all your input.

The slider pins on the front were not moving well so I'm diassembling and rebuilding them and leaving the rears to minimise cost.

Has anyone rebuilt front NB8A calipers before? These dust boots won't come off and I'm hesitant to keep yanking on them because I don't want to end up with a bit of rubber stuck down there. The other ones all came off easily but these ones are different...
https://i.imgur.com/eyB6res.jpg

The pin boots are one piece. Cut off the blind 'knob' end (other end to that shown on photo). You have to lube the outside of the new boot to get the knob end right thru' the caliper bracket hole.
The piston boots are very hard to fit. Keep trying

Thanks RS for your help again.

So I had another crack... I got a pistondust boot on, but now there isn't enough room to push the piston it? I feel like it will either just rip the dust boot off or rip. I've tried putting a piston in, then the dust boot but there doesn't seem to be room to get it in the groove? This is what the manual (Page 04-11-16 http://www.mellens.net/mazda/Mazda-Miata-1999-2001.pdf) says to do though. I'll give it another go.

Regarding that tubey rubber bit... this is the kit I bought (Meant to be OEM B2YD-33-26Z equivalent)-
www.ebay.com.au/itm/0575-BJF-Genuine-Fe ... 2563255154
If you search up that OEM part # they do look the same as the Febest kit. Febest list NB 98-05 as being compatible here:
https://shop.febest.eu/cylinder-kit-0575-bjf.html

NAY5-33-26Z has the tubular rubber bits-
https://www.atkinsrotary.com/store/94-0 ... 3-26Z.html

I think Febest have listed the wrong vehicles as compatible.