No brake fluid to the rear brakes.

I believe your problem is still the relationship between the booster rod and MC. You need to measure how far the rod protrudes from the booster and then how far into the MC it can go with something like this

https://www.harborfreight.com/6-in-digital-caliper-with-sae-and-metric-fractional-readings-63731.html

There needs to be some slack there, check the TSM.

You should also compare the shape of the rod end and the shape of the indentation it fits into to make sure they are the same. Maybe use some type of marking grease like they use on pinion to ring gear matching.

Bill O.
70 AMX

The spacers are about 5/8” thick, using a tape measure.

Mike

about 5

1970 AMX, one step forward, one step back. Both steps cost time and money.

I now have brakes!

My thanks to all of you who posted your thoughts and suggestions. All good based on the info I had provided.

My thanks to Mike here for sending me the photo that helped me resolve the issue.

So it never was ANY of the proportioning or distribution valves -front ot back.

It was the fact that I didnt install the spacers inbetween the firewall bracket and the Master cyclinder. (My only defense was that I took it apart over 3 years ago and forgot about them!-Dumb on my part!)

Tha is why there was almost no travel in the brake pedal.

After installing the spacers, -instant brake fluid to the rear! I suspect without the spacers the pushrod didnt enguage the piston sleeve- slider in the front reseviour that fills the line to the rear.

Anyway, my son came over and pumbed the brakes as I blead them.

Now I have all sorts of brake fluid at the back and front. See Mikes phoito in this trail to view the spacers behind the Booster.

My thanks to all who commented trying to help. This is such a great forum!

Sheepishly embarrased, but good lessons learned!

Tim Johnson

Well on mine, as soon as I added the 5/8 inch spacers the problem was solved.

Hope this works for you.

Tim

Tim Johnson

OK so it appears I got the switch to work an still no flow beyond the proportioning valve near the rear so thats coming apart next

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mbwicz Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Feb/20/2019 Location: Buffalo, NY Status: Offline Points: 1992	Post Options Post Reply Quote mbwicz Report Post Thanks(0) Quote Reply Posted: Mar/25/2023 at 8:51pm
	When you had your booster off, did you happen to confirm that the lever system was free and moves easily? I believe there are spacers between the booster and mounting bracket, I can check in the morning. Mike
	1970 AMX, one step forward, one step back. Both steps cost time and money.

troutwilly Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Sep/14/2007 Location: Carriere, MS Status: Offline Points: 992	Post Options Post Reply Quote troutwilly Report Post Thanks(0) Quote Reply Posted: Mar/25/2023 at 9:54pm
	I believe your problem is still the relationship between the booster rod and MC. You need to measure how far the rod protrudes from the booster and then how far into the MC it can go with something like this https://www.harborfreight.com/6-in-digital-caliper-with-sae-and-metric-fractional-readings-63731.html There needs to be some slack there, check the TSM. You should also compare the shape of the rod end and the shape of the indentation it fits into to make sure they are the same. Maybe use some type of marking grease like they use on pinion to ring gear matching.
	Bill O. 70 AMX

timj5130@gmail.com Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Mar/31/2019 Location: Madison Wi Status: Offline Points: 132	Post Options Post Reply Quote timj5130@gmail.com Report Post Thanks(0) Quote Reply Posted: Mar/26/2023 at 1:37pm
	Thanks Mike. Cany ou send a photo if you fins spacers on your AMX? Thank You Tim
	Tim Johnson

mbwicz Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Feb/20/2019 Location: Buffalo, NY Status: Offline Points: 1992	Post Options Post Reply Quote mbwicz Report Post Thanks(0) Quote Reply Posted: Mar/26/2023 at 1:54pm
	The spacers are about 5/8” thick, using a tape measure. Mike about 5
	1970 AMX, one step forward, one step back. Both steps cost time and money.

timj5130@gmail.com Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Mar/31/2019 Location: Madison Wi Status: Offline Points: 132	Post Options Post Reply Quote timj5130@gmail.com Report Post Thanks(0) Quote Reply Posted: Mar/26/2023 at 1:58pm
	Thank you for this photo! I think I have these in my garage. I took the car apart about 3 years ago to do the rotisseri thing. This would make sense in reguard to the brake pedal feeling so high when I press on it. Ill go out yhere now find them and install. Thanks again! Tim
	Tim Johnson

timj5130@gmail.com Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Mar/31/2019 Location: Madison Wi Status: Offline Points: 132	Post Options Post Reply Quote timj5130@gmail.com Report Post Thanks(1) Quote Reply Posted: Mar/26/2023 at 5:52pm
	I now have brakes! My thanks to all of you who posted your thoughts and suggestions. All good based on the info I had provided. My thanks to Mike here for sending me the photo that helped me resolve the issue. So it never was ANY of the proportioning or distribution valves -front ot back. It was the fact that I didnt install the spacers inbetween the firewall bracket and the Master cyclinder. (My only defense was that I took it apart over 3 years ago and forgot about them!-Dumb on my part!) Tha is why there was almost no travel in the brake pedal. After installing the spacers, -instant brake fluid to the rear! I suspect without the spacers the pushrod didnt enguage the piston sleeve- slider in the front reseviour that fills the line to the rear. Anyway, my son came over and pumbed the brakes as I blead them. Now I have all sorts of brake fluid at the back and front. See Mikes phoito in this trail to view the spacers behind the Booster. My thanks to all who commented trying to help. This is such a great forum! Sheepishly embarrased, but good lessons learned! Tim Johnson
	Tim Johnson

69hemibeep Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/11/2022 Location: AZ Desert Status: Offline Points: 202	Post Options Post Reply Quote 69hemibeep Report Post Thanks(0) Quote Reply Posted: Mar/29/2023 at 12:41pm
	I have the same car same issue with spacers and rebuilt the block below the heater so I will be following the suggestions made in the thread. Thanks

timj5130@gmail.com Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Mar/31/2019 Location: Madison Wi Status: Offline Points: 132	Post Options Post Reply Quote timj5130@gmail.com Report Post Thanks(0) Quote Reply Posted: Mar/29/2023 at 1:05pm
	Well on mine, as soon as I added the 5/8 inch spacers the problem was solved. Hope this works for you. Tim
	Tim Johnson

68AMXJoe Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Dec/30/2020 Location: Tampa// Status: Offline Points: 158	Post Options Post Reply Quote 68AMXJoe Report Post Thanks(0) Quote Reply Posted: Mar/29/2023 at 6:34pm
	I have a 68 AMX with the same problem also watching the post.

69hemibeep Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/11/2022 Location: AZ Desert Status: Offline Points: 202	Post Options Post Reply Quote 69hemibeep Report Post Thanks(0) Quote Reply Posted: Apr/03/2023 at 7:35am
	OK so it appears I got the switch to work an still no flow beyond the proportioning valve near the rear so thats coming apart next