Your donations help keep this valuable resource free and growing. Thank you.
|
Master cylinder differences. |
Post Reply | Page 12> |
Author | |
Doober
AMC Fan Joined: May/23/2020 Location: Indiana Status: Offline Points: 18 |
Post Options
Thanks(0)
Posted: Sep/30/2022 at 8:22pm |
Is there a difference between a manual disc master and a power disc master? Are the mounting hose spaced at different lengths? Are there any other differences? Needing the manual disc master for my 69 Rebel.
|
|
tomj
AMC Addicted Joined: Jan/27/2010 Location: earth Status: Offline Points: 7522 |
Post Options
Thanks(0)
|
This could/should be in suspension and brake... No problem though.
Disc to drum, same principles same master cyl same mounting. However, drum masters have a little check valve, a spring and plunger, hidden under the brass cone inside each output port. You can convert a drum master to disc put extracting it. The trick is to use a small sheet metal screw to grip the inside of the hole, just enough to pull it out. Use two screw drivers, one on each side under the head to lever it out. Extract spring and plunger and push it back. Do that for the front circuit only unless you have disc rears (not AMC)
|
|
1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com |
|
sweatlock
AMC Addicted Joined: Apr/28/2014 Location: Largo, FL Status: Offline Points: 3285 |
Post Options
Thanks(0)
|
The OP is asking about the difference between the master cylinders for manual and power disc brake applications.
|
|
scott
AMC Addicted Joined: Jul/10/2007 Location: Wildwood Pa. Status: Offline Points: 3498 |
Post Options
Thanks(0)
|
In 1969 there was no manual disc brake master cylinder. Power discs only. Starting in 1971, you could get manual discs. Tell us more about what you are trying to do. Convert a manual drum car to discs? Convert a power disc car to manual disc? What disc brake setup are you using??
|
|
"Prolly" is not a word.
|
|
ramblinrev
Moderator Group Joined: Dec/28/2008 Location: Wisconsin Status: Offline Points: 11476 |
Post Options
Thanks(0)
|
Scott has it right. And when there was the option of manual or power disc, they are different master cylinders. |
|
74 Hornet Hatchback X twins (since 1977)
62 American Convertible (still worth the $50 I spent in 1973!) AMCRC #513, AMO #384 70 AMX 360 4-speed (since 1981) |
|
tomj
AMC Addicted Joined: Jan/27/2010 Location: earth Status: Offline Points: 7522 |
Post Options
Thanks(0)
|
I was too long winded -- the difference between drum and disc masters is the presence of the check valve on drum masters. Remove that and a drum master cyl becomes a disc master. Therecl may be cases when disc and drum specify different masters if bore or other features change.
|
|
1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com |
|
sweatlock
AMC Addicted Joined: Apr/28/2014 Location: Largo, FL Status: Offline Points: 3285 |
Post Options
Thanks(0)
|
I re-read your response and you are correct, my mistake.
Another difference is that the reservoirs are different sizes on a disc brake master cylinder (volume) and on a drum brake master cylinder they’re the same size.
Edited by sweatlock - Oct/02/2022 at 8:22pm |
|
mbwicz
Supporter of TheAMCForum Joined: Feb/20/2019 Location: Buffalo, NY Status: Offline Points: 1983 |
Post Options
Thanks(0)
|
Just a couple of questions to the experts:
- I would expect that the leverage would be different on a manual master cylinder. Either a smaller bore master cylinder or a different brake pedal. Did AMC do either of these? I'm just thinking about the initial question, if the OP wants to take a PDB car and go to manual brakes, would he need to change the MC? Maybe his booster went bad and he just wants to run manual discs. Thanks, Mike
|
|
1970 AMX, one step forward, one step back. Both steps cost time and money.
|
|
Doober
AMC Fan Joined: May/23/2020 Location: Indiana Status: Offline Points: 18 |
Post Options
Thanks(0)
|
So, if I got a 1971 manual disc master. Would it fit a 69 Rebel that was fittedwith manual drums? Would the stubs spacing be the same? I am converting my manual drums to manual disc.
|
|
ramblinrev
Moderator Group Joined: Dec/28/2008 Location: Wisconsin Status: Offline Points: 11476 |
Post Options
Thanks(0)
|
You're probably going to have to try it and see. Buy it and compare. Return if it doesn't match the studs.
|
|
74 Hornet Hatchback X twins (since 1977)
62 American Convertible (still worth the $50 I spent in 1973!) AMCRC #513, AMO #384 70 AMX 360 4-speed (since 1981) |
|
Post Reply | Page 12> |
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 |