Your donations help keep this valuable resource free and growing. Thank you.
|
testing a brake booster |
Post Reply |
Author | |
mbwicz
Supporter of TheAMCForum Joined: Feb/20/2019 Location: Buffalo, NY Status: Offline Points: 1983 |
Post Options
Thanks(0)
Posted: Jan/23/2022 at 12:49pm |
I bought my 70 AMX without it running, but the brakes did work. I tore the car down for a complete rebuild. I've read a bunch of posts over the last 3 years about people getting their booster rebuilt. How can I test mine to see if it needs to be rebuilt? Is it as simple as putting a vacuum on it and making sure it doesn't bleed down?
Thanks, Mike
|
|
1970 AMX, one step forward, one step back. Both steps cost time and money.
|
|
6PakBee
Supporter of TheAMCForum Charter Member Joined: Jul/01/2007 Location: North Dakota Status: Online Points: 5454 |
Post Options
Thanks(0)
|
This is just spitballing so take it with a bag of salt. Get a relatively high volume vacuum pump (A/C version comes to mind) and pull about 20 InHg on the booster. Gently push the input rod into the booster in small steps. The output rod should start moving. When you stop, the output rod should stop. When you start again, the output rod should start moving out again. Then pull the input rod out, again in steps, and see if the output rod follow it. The key is that the output rod should follow the input rod. If you do this, you may want to have an assistant hold the output rod against the booster. Without the MC there is nothing to stabilize the output rod or press it back against the booster. This is so much easier with the booster in the car!
|
|
Roger Gazur
1969 'B' Scheme SC/Rambler 1970 RWB 4-spd Machine 1970 Sonic Silver auto AMX All project cars. Forum Cockroach |
|
Mopar_guy
Supporter of TheAMCForum Joined: Jun/07/2009 Location: Ohio Status: Offline Points: 4806 |
Post Options
Thanks(0)
|
IMO since you're going this far, why not get it rebuilt why it's off the car and you're not in a hurry? What's a couple hundred dollars in the big scheme of the whole project? Besides that rubber diaphragm is 50+ years old already. Just saying..
|
|
"Hemilina" My 1973, 5.7 Hemi swapped Javelin |
|
mbwicz
Supporter of TheAMCForum Joined: Feb/20/2019 Location: Buffalo, NY Status: Offline Points: 1983 |
Post Options
Thanks(0)
|
Honestly, I had it painted and reinstalled before I thought about it. My past life working on GM cars it didn't seem to be as common a problem as on the AMC's, so that is why I didn't do anything with it. But your point is valid.... Mike |
|
1970 AMX, one step forward, one step back. Both steps cost time and money.
|
|
Steve_P
AMC Addicted Charter Member Joined: Jun/28/2007 Status: Offline Points: 3760 |
Post Options
Thanks(0)
|
You can test it with a Mityvac. The boosters also commonly crack on the rear metal surface due to vibration. Mine did, and when I talked to "Booster Dewey" he said, "oh yeah, we see that all the time...."
|
|
Post Reply | |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |