brake howl

[ord27]

I put a 4 wheel disc brake kit on my '70 Coronet.
I was driving down the highway and a loud howl started from the rear left.
I consulted my friends at the resto shop, and they determined that the left brake rotor was 200 degrees hotter than the right one. The determination was that the brake was dragging. The noise stops after the brake is applied, only to return a bit later.
The emergency brake cable was adjusted and the noise stopped for a bit.
After it returned, a new caliper was installed.
The howl is back
Have any of you guys experienced this? Not sure what to do from here (except turn the radio up)

 

[Lionized]

I put a 4 wheel disc brake kit on my '70 Coronet.
I was driving down the highway and a loud howl started from the rear left.
I consulted my friends at the resto shop, and they determined that the left brake rotor was 200 degrees hotter than the right one. The determination was that the brake was dragging. The noise stops after the brake is applied, only to return a bit later.
The emergency brake cable was adjusted and the noise stopped for a bit.
After it returned, a new caliper was installed.
The howl is back
Have any of you guys experienced this? Not sure what to do from here (except turn the radio up)

Have you contacted the manufacturer regarding this to ask their advice?
Having not experienced this, it's the first place I would go.

 

[flypaper]

I would swap the rotor/caliper around side to side and see if the noise moves?
is there any adjustment on the proportion valve?
you might want to play around with that?
what kind of master set up do you have?
Brake pedal push rod adjusted correctly?
Brake Kits can be a little tricky to figure out...

 

[ord27]

there is an adjustment knob on the portioning valve. I guess I should close it more, in order to take some pressure off of the rear brakes?

 

[flypaper]

that is where I would start
then the pedal pushrod or even the Master would be my next suspect?
sounds like a slight application of sorts is happening
when it should be released free spinning and neutral
maybe the cylinder inside the of master isn't closing the port off completely
when the pedal is released?
or the seal on the cyl inside could have a defect and is internally leaking
letting out slight pressure or not fully releasing off the pressure from being applied fully and still holding back a slight amount??
they do have a specific hydraulic pressure tester (Hydrometer) specifically for that but the machine to do it is very expensive.
(that is what master cyl rebuilders use to check unit)
I used to work for a Master Cyl rebuilding company and have seen
plenty of /seals/parts/castings come out of the box and have defects.

Brake systems are a balancing act of sorts
the parts have to work together in sync together from your pedal to the wheels.
so when you start changing stuff around away from stock
it is not hard to lose that balance in some way
and it can get tricky to figure it out.
does the maker of the parts you used have any kind of support?
I would keep at it and not ignore it
you will figure it out