Doing a brake refresh. Tips and tricks?
 

Hey everyone,

I recently had a track day and ate up my current brakes pretty good. I ordered components to replace a lot of things and I'm confident in my work. I'll be replacing the pads/rotors, changing out the lines to SBG SS lines, rebuilding all four calipers, and replacing all the fluid with Endless RF650. Because this fluid is so expensive (maybe more so than I should have gotten @.@), does anyone have tips on conserving brake fluid for an efficient bleed on a near empty system? I've read about gravity bleeding, pressure bleeding, standard two man method, and by suction with a Mityvac. I've always done the two man method, however an s2000 buddy swears by the gravity method.

I've also read SBG competition brake install (basically how it'll end up for me right? :P) and they suggest filling the MC, pumping 5-6 times with the bleeder open to get fluid to the caliper, then performing a standard two man bleed (in order from furthest to closest).

Any tips are appreciated :)

Matt

I just refreshed my brake system this week. I tried out the Russell Speed Bleeders this time which allowed me to bleed the brakes by myself. Worked out pretty well so far.

Introduction - Speed Bleeders - Russell Performance Products

Watch a YouTube video or two on how to bleed brakes with a Mityvac. You can do it yourself. 2 person method is good for your Grand Dad.

I installed the AP BBK myself and bled the whole system using the MityVac. It's not an expensive tool and it will save you a lot of hassle. Proven method.

I've got a Mityvac, so perhaps I'll give it a try. I tried it on my truck and it didn't work as well as I wanted it to (the seal between the container and the lid sucks :/) so I would pump it up and open the bleeder but it would lose too much vacuum. I was looking at the brake system under the hood before I drove to work and I don't think I'll be able to gravity bleed it because the MC isn't the highest point. The lines wrap like up and around and go to the ABS pump and then go down :/

Matt

If the fluid is clean and all you're doing is getting the air out, you can reuse the fluid that gets pumped out. That is why it sucked when ATE dropped their super blue fluid. You could easily tell when you got all the old fluid out (switching between the blue and amber between changes). Another solution is to use cheaper fluid. Check your brake temps after a run and see how close they are to the rated boiling point. Brake ducts will also help.


I run ATE and haven't had any boiling issues (I'm aware of).

If you get Speedbleeders (which I love) pay extra for the stainless versions.

Speedbleeders and no issues with my car at the track.

I used a Motive Brake Bleeder when I did my brakes. It is very easy to use, work very well, and is a one man job. You don't waste much brake fluid either(if any).

If you get the Motive Brake Bleeder, be sure to get the European adapter. It's fits right on to the RX-7 brake reservoir and makes a perfect seal.

I'm getting more tempted to try this motive pressure bleeder. Are those available locally? Or is it something I'll need to order? Any specific kit to fit the MC?

Matt

I bought mine on ebay. It was $107 CDN (about 50USD) at the time. Get the European one. It screws right on the RX-7 MC and make tight seal.

Ended up buying one from Jegs. Got the "universal Import" kit. It contained the correct adapter according to their application chart. I spoke to my brother about it and he said he owns FOUR of them for his shop. So my confidence in purchase is now satisfied.

I also ordered a third bottle of the RF650 fluid so that I dont need to worry about not having enough fluid :P

From everything I've read about pressure bleeding, it seems I shouldn't have any qualms about trapping air, either in the MC or in the caliper.

I look forward to the arrival of all the pieces and I'll be updating my build and even this thread with tips in the event someone else runs into the same situation as I.

Matt

motive is where it's at. just make sure u have plenty of fluid and pressure. didn't have any issues bleeding my brakes wirh it.
Attachment 613191

For the ~20 years I've been tracking cars I've just used the cheap-o one-man brake bleed kits from parts stores with factory bleeders, never any problems. You just loosen the bleed screw with a tube going to the little bottle with handy magnet and pretend you have speed-bleeders.

I've never had any issues using off-the-shelf Pennzoil or Castrol or other name-brand DOT4 fluid at the track. I typically run Carbotech XP10 pads, fwiw.

@johnny

:icon_tup: stoked!

@ZDan

You know sometimes keeping it simple really is best :P I think it's easy to over think or over do things when all it takes is being a little old fashioned. I'm a tool guy so having those specialty tools like this is a plus. In hindsight, I'll probably go with a cheaper fluid next time. Endless provides one of the highest dry boiling points, however it definitely comes at a premium. I might opt for some Motul next time just because it's less than half the price. I suppose then I'll really be able to tell the difference in a few track events.

Matt

WTF w this Endless stuff everywhere. Crazy fanboy brain disease.

There are a million guys tracking hard in faster, heavier cars running ATE or Motul, if not plain ole Autozone Valvoline. What in the world makes people think they need imported overnighted-from-Japan JDM-yo brake fluid?

Please tell us you didn't pay $texas for Endless rotors and Project Mu pads, too. :)

Love your car and build thread btw.

Wet boiling point is more important, unless you plan to change that expensive fluid frequently (like every couple of months or so).

Get an infrared thermometer and check brake temps after your runs. There's some cooling that will happen, but you can get a rough idea how close you may be getting to the fluid's boiling point. There's no need to get 600F fluid if you're only getting to 300F

I also believe the more expensive fluid absorbs more water, so it needs to be changed more frequently (again wet boiling temps)

And ATE is like half the cost of Motul with almost similar boiling points (wet and dry)

@msilvia

Maybe my fanboy kicked in a bit. :P just a bit though. I did pay $texas for the brake fluid though. @.@ unless it pulls through big time, I'll probably go with some ATE next time. I had Super Blue in my first RX7 which was great because you could tell when it was all flushed out. It was also like 1/3 the price :P

@TomU

I think I will do that. You're definitely right that if I'm no where near approaching that brake temp that I don't need such premium fluid. This all comes with experience right? :P For how expensive that fluid was I damn sure hope I don't have to change it very often! (At least not sooner than a normal time change) ATE or Motul is looking better and better for my next flush.

Matt

Honestly, for a street driven car, the best fluid hands down is Castrol SRF.

It's expensive, but it's also not hydroscopic so it won't pick up water parked at your house. I used to use AP600 which is perfectly good when fresh, but like almost every other fluid, will pick up moisture and you'll need to flush quite a bit out to get a good firm pedal. It's not about bleeding (air) so much.

I use a ton less fluid. Basically when I swap pads for the track I open each bleeds screw (speedbleeders), give it a pump or two on the brakes and its good to go. The SRF bottle can also it on your shelf opened for months and still be usable. Not the case with others.. once you open, you better use it quick or it'll pick up water.

The only problem with the Motiv bleeder is that you're supposed to keep sufficient fluid in the tank, so although I like it I end up using more fluid than I need. Maybe I'm just inefficient with it, but it could be the opposite of the solution you want in this case.

What did you do for pads? In my experience they make a much bigger difference in fade as long as you've got fresh, "trackable" fluid.

I'd be interested to see the caliper rebuilds if you document them on the build thread. Probably a lot of us should do that too.

I ordered everything from the wonderful people at Sakebomb Garage. I got Centric flat rotors, Endless (here I go again right?) MX72 pads, their stainless braided lines, and all OEM hardware/caliper rebuild parts (through Atkins). I'll definitely be thoroughly documenting the rebuilds. I've read that in racing applications, calipers should be rebuilt every six events or so. I'm willing to bet my stock calipers have never been rebuilt so it'll be interesting to see what 23 years and 70k miles will do.

Matt

Good how to on rebuilding the fronts...

Brake Caliper Rebuild - Do-It-Yourself Instructions For Racers - Circle Track Magazine

The trick is push out all 4 pistons roughly equally at the same time. If one comes out, you loose all air pressure to the other 3 so you want all of them as close as possible to popping out at the same time. I got lucky using a single piece of wood, but one was close. Doing it again, I'd use several pieces of wood with different thicknesses where I could better control the rate they expand

I have yet to rebuild the rears

I heart Centric.

where did you get the rebuild kit for the calipers

See Here

Also Here
:p
Matt