Do not mix MOTUL RBF 600 with ATE Super Blue

i made the mistake and wasted a lot of time and money trying to fix the problem... supposedly MOTUL RBF600 doesn't like being mixed with anything else and turns into forest green 'cottage cheese' (that's what will @ SOG calls it) when mixed with ATE super blue... pedal went super mushy and had like 10% of the braking capacity... sadly this destroyed my track day cuz i had no brakes after a 10 min session

we bled the brakes 3 times and drained sludge until we drained clear blue fluid but the brakes didnt improve at all... gonna have to take it in to SOG to have it taken care of professionally

please learn from my mistake... if anyone knows of other fluids that don't like to mix well, post them up so others can avoid going through what i did

 

That sucks that you got all the way over there and found that out. Better luck next time, I think your car just likes being a SOG.

 

I just sticky'd this too. We can unstick it after awhile. I know this isn't my section, but I thought I might go through all the tech type sections and collate an FAQ? Kris, I think this is your section, do you mind?

 

That sucks Milo, sorry for your trouble.

 

Damn that sucks. Hope everything works out for you; use this as an excuse to get some SS brake lines or something.

 

That sucks man. So I assume that you didn't get to run the car at the drag because of this? At least you found out on Little Tally and not on the street when you needed them.

 

I am sorry that that happened Milo. I hope that the problem gets fixed.


Mark

 

Milo, that sucks man.

I recently swapped from 600 to super blue. I:
-Bled the 600 out of the right-rear till the resevoir was about empty and then added the blue and kept bleeding till 'dark' blue came out, and then bled a little more, bout 3 full pumps.

-I bled the other 3 corners till 'dark' blue came out and then a little more.

I think that the dark blue is important, I noticed the fluid go from gold to green to blue to dark blue to dark blue...

-I used the whole can to do a flush (1 liter i think) and the fluid has performed flawlessly for ~2k miles and ~3 hours on VIR (full course with multiple 130+ to 70 mph braking zones per lap). Its too soon to be certain but I think I like the blue more than the 600...

How much blue did you use to swap?
I thought about trying the blue and asked Ron from discovery parts how I should swap. He said to do basically the above and be sure to use the whole can.

Other brake tips for the track:

Bring spare front rotors and pads.
Always have a spare bottle of brake fluid and bleed tools.
Inspect pad thickness before each day.
Inspect rotors (for transfer, micro / macro cracks, etc) after every session. I also look over the tires after each session.
Never hold 'track-hot' pads to a non rotating rotor.
Don't use old fluid that has been cracked open / partially used aka: use a whole new bottle for what ever your doing (bleed / flush / swap).
Thinner pads (partially used) will boil fluid easier (ceramic back plates are supposed to minimize this effect, but I haven't tried).
With 600 I used to bleed (use a quart) every 2-3 track hours and flush (2 quarts) every 4 to 6. I need to see if the blue comes in smaller sizes so I can have little cans for bleeds and spares and then liter cans for flush.

Test brakes during your out/warm up lap(s). Slowly bring them up to temp, slowly ask more and more from the brakes. I generally don't go faster than 80 mph during my first 2-3 minutes on track. Once at 60ish I will toss the car back and forth a couple times (to make sure the chassis feels right and get tires warm), then accel to 80, then brake down to 50, then repeat the whole process gradually using more throttle, brake, and steering input. This whole process may also help you get mentally focused on the car/track instead of what just went on in the pits. The above may seem/look strange to others but can catch issues before your at speed.

Try not to use the brakes on your cool down lap. Use the last lap to cruise in one gear and review your line / problems / etc from a slower speed.

My brakes:

OEM brembos
OEM rotors
Stainless lines
Carbotech XP10s
front brake ducts
Super Blue fluid

 

Great advice man! Milo, sorry to hear about your brake troubles... Hopefully this will save someone from doing the same thing. You wouldn't think that two brake fluids mixed would do such a thing...

 

interesting, I hadn't thought of the ABS issue ... when I bed the brakes (which we did right after the fluid swap, cause new pads and rotors went on) I typically get into ABS during the last 1 or 2 stops; Lyman was helping me too and I believe that he also hits the threshold of ABS when he beds.

So this cottage cheese causes the pedal to drop / loose pedal pressure? Did it only 'drop' while hot or would it do this both hot and cold?

 

So despite multiple bleeds the cottage cheese kept coming out?

If the brakes were mushy cold then you have a gas in the system, right? I magin that the gas is Air... I am not familiar with the ABS and vacuum assist plumbing on the impreza but I am certain that:

gas in the Master/Slave cylinder can not be bled out, you have to pull the MC and re-fill it the hard way.

gas in the ABS may or may not bleed out.

gas in the lines / calipers would certainly bleed out.

Since you guys bled the brakes 3 times, I would guess that you have gas in the MC or ABS...

I assume the car never lost any brake fluid?

Milo, I'm not sure how old the car is and such but you may want to check and or replace the gaskets/seals in the brake system before the vacuum flush...

 

OK well I will pass this onto my co-driver that has a good bit of experiance with brake systems.

Sorry again Milo.

 

ofcourse not! sorry Zan has me running around like crazy lately so I was not able to check this.

 

As javid, I've also swapped ATE Super Blue to Motul and then Motul back to ATE Super Blue with no problems. I have an inkling that there was something else in your brake system that caused this.

I've done it on the old WRX STX car when I went from using ATE to using Super Blue.

Then again on the 05 STi, Miranda used to use ATE. I switched the car for Motul when we started to think about T2. Lately because of so much bleeding etc, I decided to switch *back* to ATE, and never had any issues.

-Tom

 

sorry i havent responded to this in a while... haven't had a chance to sit at the computer

we bled them thursday night and the pedal felt awesome... in fact i hit the brakes real hard a copule of times on the way to the track and the stopping power was unbelievable...

i had brake issues last time at tally (2 year old stock pads that burned out completely... u were there javid)... so i decided to take it easy for a few laps... during the first few laps i tried hard braking at lower speeds to make sure all was good... they responded well... then i upped my speed and started driving it harded... at the 4th or 5th lap when approaching the back straight i hit the brakes hard and engaged ABS... from the next turnb on, the pedal was mush... u know how when the car is turned off, if u pump the brakes, it builds pressure and gets real stiff? well mine didnt do that anymore... could be gas... could be sludgy fluid... whatever it was, it happened after i hit ABS

went to SOG today and bled them again after electronically engaging ABS (thanks will)... it took us about 3-4 full bleeds, even with the vacuum for pedal pressure to increase... now the pedal feels fine but i have so much baked in pad transfer that the car doesn't stop nearly as good as it used to... hope that crap burns off soon... otherwise its time to upgrade to slotted

and oh yeah, the car is an 03 wrx with ~36k miles

 

I'm glad everything got worked out. What pads are you using and where did the transfer come from?

 

its not any motul in general its specifically the rbf 600 that did this, it wont do it with the motul 5.1, so if thats what you guys were running that would explain things.

 

the pedal feels fine but the brakes r still crap... however the braking is MUCH better than it was before will worked on it

i was using carbotech bobcats... when my brakes died on the track, i pulled into the pits and looked at them... the rotors looked real bad... when it cooled off, we tried to take the calipers off to check on the pads... however the pistons had clamped onto the pads pretty firmly and it took some force from ryan (wrxguy) and myself to get them off... we think the fluid turned to jelly and expanded applying a constant force to the pads... when i pulled the pads, they had molted pad material around the edges... im guessing this is what caused to massive amounts of transfer

 

i bought a ton of ATE today... u can have some for ur experiments... u can get motul at atlanta triumph & ducati on piedmont

 

wrx-wrc: Tom and I both use the 600.
milo:
1: turn rotors
2: get real pads (XP8s)
3: ????
4: profit

alex: Hoppe has both the ate and the 600 at home. He was planning to mix them up, but you may want to remind him (use our blog at trackmonkey).

 

mine have been turned 2-3 times already... i need to save a little and get slotted... hopefully by next month

haven't done my research on track pads... in the future i plan to keep a set of good track pads that i will use at the track only... don't want something too abrasive that would kill my rotors by driving daily... i thought the bobcats were satisfactory for daily driving and autoX

hahahahaha... i think i know where ur going with this :rofl:

 

my next set of rotors will be cyro treated, just a thought for you

 

Hey Milo, the XP-9's have been on my stock rotors for 10k miles now with no issues other than squeeking and dust. Daily driven of course and no unusual wear.

 

how much did the xp-9s run u guys? i need to do a little research and find out if they work for WRX

 

F&R on 05 STi $335.

 

Short answer: yes

As brian noted, they are VERY rotor freindly, both on track (hot) and on street (cold). Also, you can use XPs on the street, they will stop the car just fine even cold; if you want, you can drive my car cold and go to the brakes hard and it will stop quicker than 99% of the other cars on the road. Of course once the pads are hot, they will brake even better. The XPs are also very linear, the clamping force goes up with pedal presure in a linear manner; some pads are like light switches, XPs are not. Down side is that they dust more than other brands (however the dust has no iron which will stain your clearcoat.... turing it rust-orange).

XPs will dominate HP+'s all day long!

 

those r the pads i'll be upgrading to them

thanks guys

 

I am glad that things worked out well at SoG,Milo. It was a good learning experience for me to observe and help when needed. I hope that the braking will get better soon too.


Mark

 

Alex, Miloman - If you call Carbotech directly and use the "Hoppe is a pussy" discount code, you get 10% off. They sponsor the race car

-Tom

 

As jacko said, I've got a bottle of both fluids sitting in the garage and tonight I'll be up or a little chemistry action and try mixing both of the fluids, as well as trying to boil them. I wonder how that will smell in teh kitchen.

Tittywop to follow.

-Tom

 

it will smell absolutely horrid, but have fun

 

Tom already smells bad, lol

 

now i know what not to do.. thanks milo

 

Any updates? Could anyone replicate that in an experimental fashion? It is safe to combine the motul fluid with the stock brake fluid though, right?

 

by mix u mean bleed the stock fluid out and fill it with MOTUL then yes you should be fine... but please stick with MOTUL and don't use anything else after that

im not sure thats what caused the problem but there have been a few people who have had issues in the past... and there have also been people who have had no issues mixing them... in the future i'll probably just use ATE

 

Sorry, this is a bit off-topic but when i bleed the brakes should i remove all of the stock brake fluid?

 

not sure if u know but there's a specific order to bleed the brakes... there are good writeups on scoobymods.com
http://www.scoobymods.com/forums/showthread.php?s=&postid=6623

 

Thank you for the information guys. I've bled brakes before but i hadn't completely replaced the brake fluid in the system. I hope 2 bottles of motul are enough...