65 F-85 brakes
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65 F-85 brakes
Hey-
I'm having some problems with my 65 F-85's brakes and would like to know if anyone on the list has ideas as to what might be the problem with them.
Basically, the car had it's original single master cylinder, non-power, 4 wheel drum brakes, which originally worked just fine and did a good job stopping the car.
For safety reasons, I decided to convert the car over to a dual reservoir master cylinder. I found that using the master cylinder out of a 67 Cutlass would work since it has the same bore size, but there were some differences in how the master cylinder would bolt up to the firewall and also differences in the depth the pushrod would go into the plunger (don't know what else to call it) in the back of the master cylinder.
I eventually found that a Year One dual reservoir master cylinder would have the right bore size, plunger depth, and would bolt up correctly to the firewall, so I went that route.
Since that time, although the brakes DO work, I've never been very satisfied with the car's braking performance. For one thing, pedal effort is higher and the brakes seem to engage more slowly than they did with the single res. m/c. When I remove my foot from the pedal, the brakes also seem to disengage more slowly.
I have found that I have problems when taking the car on long trips, as pedal effort gets VERY hard and stopping the car becomes extremely difficult. It seems to me that the brakes are dragging somehow. For whatever reason this is not much of a problem on short around town trips.
I don't fully understand what the problem is here. My one guess is this. With the old setup, there was a 5/16" line going from the m/c down to the junction block, with three 3/16" lines going to the left front, right front, and rear of the car.
With the new setup, I have 3/16" lines leading from one reservoir of the m/c to the junction block (now used for the front brakes only) or from the other reservoir of the m/c directly to the rear of the car.
I made no changes to the wheel cylinders or anything like that.
I'm wondering if it's possible that the 3/16" lines from the m/c to the junction block are too restrictive? Perhaps I need to use 1/4" lines? But if I do that, the fitting size will be wrong and I won't be able to screw the fitting into the m/c and the junction block.
Am I on the right track? Or is it something else I've overlooked?
Any brake experts here?
Thanks,
Scott
I'm having some problems with my 65 F-85's brakes and would like to know if anyone on the list has ideas as to what might be the problem with them.
Basically, the car had it's original single master cylinder, non-power, 4 wheel drum brakes, which originally worked just fine and did a good job stopping the car.
For safety reasons, I decided to convert the car over to a dual reservoir master cylinder. I found that using the master cylinder out of a 67 Cutlass would work since it has the same bore size, but there were some differences in how the master cylinder would bolt up to the firewall and also differences in the depth the pushrod would go into the plunger (don't know what else to call it) in the back of the master cylinder.
I eventually found that a Year One dual reservoir master cylinder would have the right bore size, plunger depth, and would bolt up correctly to the firewall, so I went that route.
Since that time, although the brakes DO work, I've never been very satisfied with the car's braking performance. For one thing, pedal effort is higher and the brakes seem to engage more slowly than they did with the single res. m/c. When I remove my foot from the pedal, the brakes also seem to disengage more slowly.
I have found that I have problems when taking the car on long trips, as pedal effort gets VERY hard and stopping the car becomes extremely difficult. It seems to me that the brakes are dragging somehow. For whatever reason this is not much of a problem on short around town trips.
I don't fully understand what the problem is here. My one guess is this. With the old setup, there was a 5/16" line going from the m/c down to the junction block, with three 3/16" lines going to the left front, right front, and rear of the car.
With the new setup, I have 3/16" lines leading from one reservoir of the m/c to the junction block (now used for the front brakes only) or from the other reservoir of the m/c directly to the rear of the car.
I made no changes to the wheel cylinders or anything like that.
I'm wondering if it's possible that the 3/16" lines from the m/c to the junction block are too restrictive? Perhaps I need to use 1/4" lines? But if I do that, the fitting size will be wrong and I won't be able to screw the fitting into the m/c and the junction block.
Am I on the right track? Or is it something else I've overlooked?
Any brake experts here?
Thanks,
Scott
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