SICAMG

Looking to swap out front caliper rubber lines to stainless. Any input as to the easy way of bleeding would be great.
Should I do a Star "brake bleed" or shut the system off and do a traditional pressure bleed from the master with a pressure pump? Thanks

shardul

iTrader: (1)

i may have some new SS brake lines. PM me with a price if you are interested

SICAMG

Thanks Shardul but I already have the lines ...just was wondering about an easy way to bleed the calipers out. Thanks

shardul

iTrader: (1)

DAS and Pressure bleeder

nanayaw6

I've always wondered if there's a benefit to running SS Lines with SBC? What improvements can be had?

SICAMG

I put stainless lines on every car I have built. Right off the bat the "spongyness" feel when pushing hard on the pedal is much less. Plus there is a real difference when you have a system like ours our say a Hydraboost brake system that develops a lot of pressure beyond what a conventional brake system will produce.

DVC

Since we're pushing on a switch with no mechanical-hydraulic connection, it's hard to believe you will notice a tactile difference.

SICAMG

Put a gauge on a brake caliper to measure pressure and document your readings.That pressure is hydraulic and that rubber hose is how its getting to the caliper. Put a very soft hose on it and it will expand as the pressure builds...a solid line...no expansion so a big difference in pedal "feel". Also you are not pushing on a switch...it is a master cylinder that feeds the SBC unit brake fluid/pressure. Then it gets complicated from there LOL

DVC

Thanks. I understand the expanding of the hose but not the M/C to pedal correlation on the brake by wire.

I tried bleeding with my Star and it used so much damn fluid, that the next time I did it, I used just the Motive pressure on the res and a MAC vacuum on the bleeder. Worked really well.

SICAMG

Not so much brake by wire. The master is feeding pressure to the SBC unit. The SBC then does its thing and pushes fluid to the calipers. Again it gets complicated from there as the electronics and hydraulics work together to stop the car. Also to complicate things the SBC has over 1,500 psi stored in the reservoir and that's what you have to be careful with. I myself have never bled this system so that is what I will be doing tonight.

nanayaw6

Did you disable SBC with star or unplug the electrical connector and then used the Pressure bleeder and MAC vacuum ? Roughly How much fluid did you end up using with this method?

SICAMG

I have star but I just unpluged it. What I did was leave the new line fitting loose at the solid line connection,pushed back a piston to get all the air out of the new line than tightened it up. This way most of the air was pushed out before I even began bleeding. From there pressure bled. All set.

nanayaw6

That's smart what you did to get most of the air out. I did the star flush this weekend when I painted my calipers and of course it glitched out when I was on the last nipple on the last caliper. Do not planning on relying on it for the next round of flush.

DVC

Have done it both ways and feel they were both equally effective. I won't spend the time getting SDS out next time. Hmm, I'm sorry I can't recall the amount of fluid.

SICAMG

Well I screwed myself some how....Never drove the car until tonight and the SBC stop light is on so some air must be in there.... Ok so I figure I might as well bleed all the old fluid out on all calipers and put some fresh stuff in. Got everything hooked up,hook up DAS,go to bleed menu,start at right rear,go to left rear then left front.....but I here the right front caliper trying to come on ???? What the hell is this all about. It says to go in a particular order but something is not right and now I cant bleed the system. So what did I do wrong? Also do I need to have the pressure bleeder hooked up to the master as well. It did bleed the rears correctly with out it but that was it. I am missing something here. Thanks for any help.

DVC

Leave SDS out of it. Do it again with SBC unplugged or battery unhooked. Get 2.2 bar on the reservoir. Same order RR, LR, LF, RF.

SICAMG

OK I will hit it again tomorrow.. I really get pissed off when I f-up a simple task I have done 100s of times. The esp,brake lights are on and it runs poorly because the ecm see's something up.These systems are not very forgiving!! Thanks for the info.

nanayaw6

SICAMG I feel your pain man. Such a simple task but no, thanks to MB electronics. My STAR glitched out when I was on the last caliper (right front) when I worked on it last weekend and so I'm going at it again today. Also I am not entirely convinced that the left front inner caliper was bled right since it was so short and not much fluid came out compared to the outer nipple. Star detected that there must be air in the system as the pressure drops when checked with star. Also the brake pedal feels a bit too firm (like a conventional brake system with the car off). DVC, thanks for the tips. I'll be picking up a bit of fluid today and will give star one last go just to clear any existing errors then maybe follow up with the conventional bleed as you suggested and like I have done on so many other cars. Really not loving SBC this week. One thing though DVC, mine used just under 2.5L of fluid and that included filling the reservoir to the line afterwards. Granted not much happened with the inner calipers but I still had about 1/4L left in the bleeder when I was done. The right rear caliper consumed significantly more fluid than the others though.

SICAMG

When you do yours is it normal to have that loud noise with the pump when bleeding?
Do you have any lights on...esp, brake light and red STOP light on cluster?


Yes when I redid mine I was at the drivers front and could hear the passenger front caliper clamping on and off so it was trying to do the wrong side even though I was following what the screen was telling me. From there it went down hill. You have know idea how pissed I am because I might miss a great opportunity to make some passes at a small airport and now this crap because I had to have stainless lines!!!!LOL

nanayaw6

Yes mine activates the pump a few times then the fluid gushes out after the pump stops and the sbc valves open. I heard that clamping sound from the front calipers too and figured it helps knock air bubbles loose from the calipers.
The warnings on the cluster come on every time I connect with star. I brought this on myself trying to have fresh fluid in there for some 1/2 mile air strip runs ending of this month.

SICAMG

Holy crap man i am trying to do the same thing!!! 3/4 mile air port but not a standing start. Will be from a roll, U turn at the end and will be around 40mph when I start.

One more thing I just found out....my wife who was helping me said that the "SBC voltage" "words" kept showing on the screen. I wonder if that threw a wrench into it. I had the charger on it but I guess it couldn't keep up..... but the pump did run ok. Who knows.

SICAMG

So this is where I am at. Had to reset all the pressure in the sbc with the DAS and thats why it would not bleed again. But.........the problem is the test is showing there is air in the system and that the "right front pressure sensor" is not working. There is 0 psi on that caliper after the test.

Where the hell is the pressure sensor? Could there be air near it and it will not read pressure.

I am going to bleed the system with a pressure bleeder and see what I get but my bleeder is leaking so a new one is on the way.

Anyone have some ideas? Again all I did was put on two front brake lines and all was fine before hand. Also there is only 172,000 actuations on the SBC.

nanayaw6

I got a similar message when I first mounted my calipers after painting. I did a second pressure test and the right front caliper pressure sensor was reading just like the others instead of a drastically low reading before.
On a side note, my second flush with SBC went through and now the pedal feels as it should.

SICAMG

Well I will try bleeding with DAS one more time. I dont understand why it just quit when it got to the front caliper. I am running out of time for the airport run as well. This sucks!!!!

nanayaw6

..