[BRAKE EXPERTS] Master Cylinder/Junction Block question
Thread Starter
Le Mans Master
Joined: Aug 2001
Posts: 6,071
Likes: 297
From: Savannah GA
Cruise-In IV Veteran
[BRAKE EXPERTS] Master Cylinder/Junction Block question
I am about to install a brake proportioning valve and just want to make sure I have my lines correct. It looks like the rear of the junction block has a bolt that can be removed to install the bias spring. Logic would tell me that it is inline with the rear brake circuit. So if I am correct, the rear brake circuit comes from the front of the master to the rear of the junction block??? The front of the junction block has a sensor which I assume may detect low pressure.
The DRM instructions for their spring is vague to say the least. So can someone verify which set of lines in the junction block I tap into for the rear brake proportioning valve?
Thanks, Michael.
The DRM instructions for their spring is vague to say the least. So can someone verify which set of lines in the junction block I tap into for the rear brake proportioning valve?
Thanks, Michael.
Drifting
Joined: Jul 2002
Posts: 1,484
Likes: 0
From: Morgan Hill Ca.
Re: [BRAKE EXPERTS] Master Cylinder/Junction Block question (C5-VERT)
Mmmmm? There is only one junction block and that is right below (or almost below) the master cylinder. I recommend that you take the junction block out to install the bias spring, and be careful as the cap is aluminum and the block is brass. The cap is a hard push to get it back on with the new spring and it will cross thread or strip very easily. Just disconnect the brake lines to the block and plug them, then wrap a rag around it and put it in the vice and unscrew the alum. cap (carefully) remove the old spring and put in the new (being careful to replace the washer and seals exactly as stock). Put the cap back on and and install the block. All the lines should match up as when you took them out.
Also be careful your master cylinder does not bleed dry, keep the lines plugged.
Jer
Also be careful your master cylinder does not bleed dry, keep the lines plugged.
Jer
Thread Starter
Le Mans Master
Joined: Aug 2001
Posts: 6,071
Likes: 297
From: Savannah GA
Cruise-In IV Veteran
Re: [BRAKE EXPERTS] Master Cylinder/Junction Block question (BlueDragon)
Thanks for the help. I am not installing the DRM spring but instead installing a proportioning valve after the junction block. In which case I would remove the spring all together. I just need to know which lines in the junction block feed the rear brakes. From what you said it sounds like the rear lines where the aluminum plug resides.
Drifting
Joined: Jul 2002
Posts: 1,484
Likes: 0
From: Morgan Hill Ca.
Re: [BRAKE EXPERTS] Master Cylinder/Junction Block question (C5-VERT)
Yup,
There is a short line that goes from the Master cyl down to the block, and I think there are two lines out of it. I can't remember where the two go, or it could be one line. Heck I got to go look. Will get back to you, but you should be able to trace them down. Thats the problem with being at work!!!!!
Jer
There is a short line that goes from the Master cyl down to the block, and I think there are two lines out of it. I can't remember where the two go, or it could be one line. Heck I got to go look. Will get back to you, but you should be able to trace them down. Thats the problem with being at work!!!!!
Jer
Thread Starter
Le Mans Master
Joined: Aug 2001
Posts: 6,071
Likes: 297
From: Savannah GA
Cruise-In IV Veteran
Re: [BRAKE EXPERTS] Master Cylinder/Junction Block question (BlueDragon)
There are two lines coming from the master, the front line(facing the front of the car) goes to the rear of the junction block(where the spring is). The rear line coming out of the master goes to the front of the junction block. So it makes sense to me the front line of the master is for the rear brakes and the rear line coming out of the master is for the front brakes.
Thread Starter
Le Mans Master
Joined: Aug 2001
Posts: 6,071
Likes: 297
From: Savannah GA
Cruise-In IV Veteran
Re: [BRAKE EXPERTS] Master Cylinder/Junction Block question (C5-VERT)
Well I got everything installed but after bleeding everything sufficiently(2 bottles of Motul), or atleast I hope so, the brakes still feel like they have air. The gauge on the proportioning valve only reads 500psi when you jam the brakes and then goes down to zero after about a second. I have no clue what is going on. Anyone have any ideas?
I adjusted the valve in all variations but it did not matter. Maybe because I removed the juction block I have air in the ABS system? I did not let the master loose any fluid though.
Another thing is I removed the bias spring from the junction block b/c I figured I would want the prop. valve to control all the pressure. The bolt that holds the spring in has a rubber stopper which plugs a hole. So in otherwords I had to leave the plastic internals minus the spring intact to prevent the rubber plug from leaking fluid. So does anyone think that may be the problem?
When I bled my brakes it also seemed that my front brakes pushed ALOT more fluid out than the rear. I know it should be less but I remember it flowing more than what it did.
Here are some pics of the install...[click for full size]
[Modified by C5-VERT, 2:58 AM 5/15/2003]
I adjusted the valve in all variations but it did not matter. Maybe because I removed the juction block I have air in the ABS system? I did not let the master loose any fluid though.
Another thing is I removed the bias spring from the junction block b/c I figured I would want the prop. valve to control all the pressure. The bolt that holds the spring in has a rubber stopper which plugs a hole. So in otherwords I had to leave the plastic internals minus the spring intact to prevent the rubber plug from leaking fluid. So does anyone think that may be the problem?
When I bled my brakes it also seemed that my front brakes pushed ALOT more fluid out than the rear. I know it should be less but I remember it flowing more than what it did.
Here are some pics of the install...[click for full size]
[Modified by C5-VERT, 2:58 AM 5/15/2003]
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