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-   -   Independant hydro setup won't lock up wheels (https://www.rx7club.com/drifting-226/independant-hydro-setup-wont-lock-up-wheels-1058338/)

Digi7ech 03-01-14 04:17 PM

Independant hydro setup won't lock up wheels
 
I've got racefab dual caliper kit with a pair of rebuilt calipers. Then Standard Hydro ebrake handle with wilwood .75 cylinder.

I've bench bled the cylinder in car. Then bled the liens and calipers but can't get the setup to give me a locking feel.

I have to pump it a bunch of times for it to build pressure in the lines. Then it will apply enough pressure to the discs to prevent hand turning of the rotors with the handle engaged or not.

If I let the handle fully extend back to rest, you can see the reservoir fill back up with the fluid it pumped into the lines.

Then the handle goes back to limp and needing to be pumped.

Driving around, it's like I'm not even pulling the handle. Once pumped to pressure, it just adds drag the to car while in motion.

Any tips? or hints? I've bled the system a couple times by now.
http://s23.postimg.org/gsnd7uywr/20140121_210214.jpg
http://s22.postimg.org/mj0bh4fox/20140218_205910.jpg

ksnew 03-01-14 09:41 PM

To me it sounds like you need to bleed the system, maybe look into renting/buying a vacuum bleeder? I suppose it's possible the master cylinder could somehow be faulty. Unlikely, but it's a possibility. Also, do you know the condition of the 2nd set of calipers you added? I have his fd setup and don't have any issues with mine not wanting to lock (when turning by hand since my pos hasn't ran in like 2 years lol)

Digi7ech 03-01-14 10:44 PM

I'll probably borrow a mighty vac setup.

Previous chinese .70 cylinder did same thing.

Calipers were from junk yard. I disassembled them and rebuilt them with a new kit.

ComicArtist 03-02-14 10:27 AM

It's not bled enough. Every hydro setup I've installed has taken seriously a vacuum bleeder, then about 30 minutes of pumping to actually build the pressure to lock the rears.

NWHero 03-03-14 11:10 AM

every hydo setup i've installed required a ridiculous amount of bleeding. bleed it, bleed it, bleed it again, keep bleeding, bleed some more, and now MAYBE its good enough.

usually end up going through a whole pint bottle of fluid.

Digi7ech 03-03-14 12:32 PM

Got a mightyvac last night and spent about 20 minutes per caliper bleeding it.

My caliper valves were introducing air into the vacuum when cracked open so I put a bit of teflon tape on them so it would suck the system better.

Still same deal. Limp handle at first, then it will built some feedback but not much. If I release the handle,it will release the built up fluid back into the rez.

I'll keep trying to bleed it. Should I try reverse bleeding from the reservoir?
The mightvac setup has a suction cup adapter. Maybe I'll bleed the rez down from the caliper a bit, then put the caliper line in a container of fluid and suck from the reservoir till it's full again?

mannykiller 03-04-14 10:12 AM

^No. Do yourself a favor and get some good quality speed bleeder valves. They'll change your life forever. It'll take you 5 min to bleed it...and you'll kick yourself in the ass for not doing it sooner. I have speed bleeders on all my fluid lines. All 4 brake calipers, clutch line.. and soon enough A hydro set up as well.

Digi7ech 03-10-14 07:14 PM

Was at Vegas Proam this weekend and met a guy with the same exact setup(different brand MC, but same handle and racefab setup).

He couldn't get his bled either. He said he had to take the calipers off the mounts and put a block of wood in it to halt the piston. Then raised the caliper up and bled it.

I'll try this soon. I'm wondering if the caliper can't be properly bled in this configuration. It's essentially upside down from the stock design. Maybe there's a unbleedable air pocket in it.

moremazda 03-10-14 07:47 PM


Originally Posted by Digi7ech (Post 11695732)
Was at Vegas Proam this weekend and met a guy with the same exact setup(different brand MC, but same handle and racefab setup).

He couldn't get his bled either. He said he had to take the calipers off the mounts and put a block of wood in it to halt the piston. Then raised the caliper up and bled it.

I'll try this soon. I'm wondering if the caliper can't be properly bled in this configuration. It's essentially upside down from the stock design. Maybe there's a unbleedable air pocket in it.

Try a 2psi check valve. Makes bleeding easier and will keep the fluid from pushing back into reservoir. And 2psi should be enough residual pressure to keep the handle firm in between pulls.

http://www.summitracing.com/parts/wi...1874/overview/

ComicArtist 03-12-14 10:33 AM

Just thought of something else, have you checked to see what way the calipers are on? The bleeder nipple needs to be on the top of the caliper, and since you're installing it on the back side of the rotor, you need to put the drivers side caliper on the passenger side and the passenger side caliper on the drivers side. Just occurred to me that if they were upside down it would cause the problems you're having.

joshuaput 03-14-14 11:33 AM

i didnt read what any of these dudes said. but from the look of it you have a ton of air in your line... which also looks to be shitty. my guess is that if you got rid of the air your line would just expand when you pulled the handle. looks like its that cheap line they give you with your catch cans. you need hydraulic lines.

Digi7ech 03-14-14 12:14 PM

^and if you notice that line you see is going from the outlet right back into the reservoir. That's a pic of me bench bleeding the cylinder before connecting it to the brake line banjo sitting on the bottom right.

The reservoir line is 4an pushlock with brake fluid approved hose.

Comicartist,
I'm thinking the same thing. The calipers essentially are rotated on the caliper so the top bleeder became the bottom bleeder and by chance our calipers have a second nipple, which is now the "top" bleeder. My guess is that there is some kind of unbleedable air pocket when in this configuration.

//
That 2psi check valve may be the answer too. I might take out my MC to rear line and have the brake shop put that inline.

patman 03-14-14 04:42 PM

You have the second caliper on upside down, which means the bleeder screw is on the bottom. Only way you are going to bleed that is to take it off and turn it over, or drill and tap another bleeder screw in the correct location. Air rises to the top, you can bleed that bottom screw til your arm falls off and nothing will happen.

Digi7ech 04-02-14 02:15 PM

an update for anyone looking at this with similar issues.

Removed calipers from the mounts and bled them on top of the rotors with the bleed nipples facing up. Used a C clamp to hold the piston in.

The ebrake now has a solid feel.

It still won't lock, but it definitely works now.
Next step is to mount the handle in the car so I can put some strength/leverage into it without ripping it off the tranny tunnel.

mannykiller 04-08-14 10:53 AM

The calipers are on the wrong side like everyone else said. You'll struggle with it until you swap calipers to the opposite side. If you were to do that and you got 2 speed bleeders life would be a million times easier.

Digi7ech 04-09-14 05:46 PM

^can't be done.

I removed the calipers during that bleeding period to see if that would work. They physically can't work with the racefab mounts. It hits the hub before getting close to slipping on the rotor.

//Also, I used the ebrake this weekend at a drift event. Works great. The pads were new and I think they needed to cycle in before getting a decent bite.


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