For my 70, the distribution blocks are the same whether it's 4 wheel drum or disc/drum. Also, the distribution block is different 69 to 70 (fitting for the line to the rear is different), so if you're replacing it you may need to determine whether it's specific to 1967. Somehow I've ended up with 2 NOS ones for my 1970.
As a last resort, do a full brake bleed. It's possible the rear system has some air present, causing enough of a pressure differential to trip the spool, but not enough that you'd feel it in the braking.
I might be in the minority here Greg, but if you have good brakes, no leaks and you know you car well enough to recognize a braking issue, disconnect the lead from the block. If you'd never had the lines off the block, you could be in for an adventure getting them off and onto a replacement. Even with the possible transfer of fluid between the system seals tripping the switch, I can't see it ever being the source of any type of future brake failure.
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65 Laurentian post, 67 Grande Parisienne 4 door HT.
If your light is on and you hit the pedal as hard as you can with your heel and it goes out, then youve got air in the system or your master is bypassing fluid. In all the years Ive been pulling wrenches Ive yet to replace one of those blocks.
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'68 Parisienne 2+2 Convertible Matador Red (Resale Red but not for sale).
Oh. And also when trying to bleed you need to center that block (light out) before finishing bleeding. Or the one system is blocked off and cant bleed. If you have access to a vacuum bleeder you may have better luck.
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'68 Parisienne 2+2 Convertible Matador Red (Resale Red but not for sale).
If your light is on and you hit the pedal as hard as you can with your heel and it goes out, then youve got air in the system or your master is bypassing fluid. In all the years Ive been pulling wrenches Ive yet to replace one of those blocks.
I agree that the block is probably ok. In almost 50 years of pulling wrenches I have only changed two of those blocks. One was made of steel or cast iron and was leaking due to rust, I am in Ontario, the other was a proportioning valve type leaking out of the proportion valve section because of oil in the brake system. Some can be hard to centre after bleeding the brakes and I agree that there may be a bit of air or a master cylinder starting to bypass.
