Line lock won't hold front brakes

[cu440da]

I have manual disc/drum brakes (late model alum master, stock distribution block). Single in/out line-lock is between master and dist block. They will lock somewhat, but will not hold car when any power is applied.

Bench bled the master- then the system- and bled, bled, and bled again to no avail.


Overall, the brakes (completely new) have never really felt 100% . The pedal is firm, but they just don't feel like they're working well. Panic stops from around 30 mph result in no tire lockup front or rear.

Any thoughts on this?

[GON_RACIN]

Stupid question, but is the line lock installed on the proper line coming out of the MC?  I cant remember who but I vaguely remember seeing an underhood pic of someones car on here, and I recall seeing the line lock solenoid installed on the wrong brake line. 

[Blvedere]

Did the brakes work okay before you installed the line lock?  Don't know for certain,but I don't think line locks work all that well with disc brakes. I am more than likely wrong on that, but that has been my experience. How hard are you pushing on the brake pedal when you are setting the line lock?

[MVRCorp]

 

[chryco]

Are your front shoes set up high enough? You may have to pump up the brakes a few times then set the line lock.

[PureGTS]

  I had to do the same thing, pumping the brakes before setting the line lock. But with my car, using the OEM disc brakes, I found the car still creeping during the burnouts so I've never tried anything past that. I don't really use it anymore and just foot brake the car. If I really had a pair, I'd remove it just for the weight savings. 

[coors00]

It needs to be installed after the valve, and the brakes; not between the master and valve.

[cu440da]

Did the brakes work okay before you installed the line lock?

No idea, car was bought with no brakes. All parts were new and installed at the same time.

Are your front shoes set up high enough? You may have to pump up the brakes a few times then set the line lock.

I have discs, and I pump the snot out of them till the pedal is rock hard and hit the switch. It holds the car at rest, but if I put it in gear it will start to slip, like there is not enough pressure.

It needs to be installed after the valve, and the brakes; not between the master and valve.

It is a Jegs single line in and out line lock. I dont see how it could be installed like that. Are you saying I would need one line lock for each front wheel?

[william]

It maybe the master cyl.
What is the bore size?
Try one with a smaller bore size it will have higher line pressure for the same pedal pressure but will have more pedal travel.

[coors00]

I have a Jeg's. You plug one front line at the valve, run the other front line to the lock; then coming out of the lock, use a tee, to splice both front lines together.

[mrspeeddemon]

i'm running a jegs line loc between the master and the block and seems to work damn good. I don't see how it would make sence to plug the lin on the distribution block and then run a T. isn't the job of the distribution block to even the pressure between the front brakes- one long line and one short line- the only way a t would work is if it was evenly spaced between the two.

[coors00]

the block's job is to cut off the front or back brakes, if a leak occurs, allowing you to use the good end brakes to stop.
The Jeg's instructions say to install it after the block, with a tee.

[coors00]

Let me expand on that; it is actually a combination valve, that also reduces pressure to the rear brakes.

[cu440da]

From what I have read, '67's are a simple distribution block, not a proportioning valve. Would this still need to be installed as you mentioned? It seems as if I'd be doing the same thing as the stock block.

[NYrr496]

I've heard of having to pump the pedal a few times to build pressure, but how 'bout this: How big are your brakes? If it's a small diameter rotor, it may not be able to hold the engine back.

[Nitrous340dart]

I had the 4-piston disc on my 67, I can't remember what master but it had dual reservoirs.  A hurst line lock inbetween the master and the front brakes and just a willwood prop. valve for the rear.  No factory blocks or valves.  I would have to pump it a couple times to get it to hold, but if the ground was wet at all or front wheels on paint marks or something it would push my locked up front brakes a little.

[4Huntin]

Have you tried to hold the button while you pump the brakes my pedal stays firm when i do this.
It wont hold at the light tho so i footbrake there.
Steve

[cu440da]

    

I'm not even sure I want to admit what was happening here. I plumbed the brakes wrong. Not just a "Whoops, that's not right."- more like a "WTF?! How the hell did I do that?" kind of screwup.

Everything was backwards. Rear brakes had the line locked, running off the wrong part of the master. Worst part is- I knew the front brakes ran off the rear of the master and I'm pretty sure I knew what port it needed to go to on the dist block. 

  doesn't even begin to describe this. My car should have a restraining order against me keeping me 500 ft away from the garage.

[Dartagnan]

hey sh*t happens  glad you found problem    hey if you had it  on rears how were they spinning 

[A13Dart]

Just to follow up, the factory distribution block isolates the front brakes from the rear brakes.  The line lock can be installed between the master cylinder and the distribution block.  The only thing that will happen is the brake system warning light will come on when there is a differential in pressure between the front and rear systems.

[cu440da]

Yeah, it's a handy little line lock indicator light.

Sooo..the brakes work well when they are done right. Front brakes now lock like they should.

Sorry I took you all on a wild goose chase, thanks to all who responded.

[cu440da]

Stupid question, but is the line lock installed on the proper line coming out of the MC?  I cant remember who but I vaguely remember seeing an underhood pic of someones car on here, and I recall seeing the line lock solenoid installed on the wrong brake line. 

Not so stupid after all, that may have been me. You weren't just trying to spare my feelings were you?

[chryco]

Hey ! Just wondering if maybe the valve got installed in reverse . The valve IN and Out are directional and if reversed will bleed back and not hold . Can you try and switch it to try?
    Chryco

[coors00]

The Jegs is marked well; guess they had too many phone calls at first.

[cu440da]

I had that right, which is remarkable in itself.

[coors00]

Hey, I launched the car in reverse once..... never seen an oil filter rupture.
With all the blue smoke, I thought the engine was trashed.

[GON_RACIN]

Stupid question, but is the line lock installed on the proper line coming out of the MC?  I cant remember who but I vaguely remember seeing an underhood pic of someones car on here, and I recall seeing the line lock solenoid installed on the wrong brake line. 

Not so stupid after all, that may have been me. You weren't just trying to spare my feelings were you?

Na, I spare no feelings.   I saw the pic while cruising this site and doing a million other things at once.  I had forgotten all about it until you posted the question.  Glad you found the problem. 

[flyboy01]

   

I'm not even sure I want to admit what was happening here. I plumbed the brakes wrong. Not just a "Whoops, that's not right."- more like a "WTF?! How the hell did I do that?" kind of screwup.

Everything was backwards. Rear brakes had the line locked, running off the wrong part of the master. Worst part is- I knew the front brakes ran off the rear of the master and I'm pretty sure I knew what port it needed to go to on the dist block. 

  doesn't even begin to describe this. My car should have a restraining order against me keeping me 500 ft away from the garage.

I would like to know what roads you drive on so I can avoid your car.