Import Master Cylinder Identification/replacement

Hello all,

Well as i piece back together my Jeep, Frankie, and try to bleed the new brakes i noticed that i have air coming out of the VacuumAssist (name?)...aka big round thing, when pressing on the peddle. It is coming out between the "big round thing" and where the reservoir attaches. When appart is the rod pushing in to the reservoir that is leaking air around the diaphragm. The reservoir appears ok at this point.

My question is this is this appears to be from an Japanese import vehicle...70s/80's i guess. Early attempts to match the part is not working.

Suggestions, without totalk peddle makeover at this time, on what to do?

The PO installed this along with 11" drums all around so i am thankful for the upgrade.

 

If you can identify the master cylinder it may lead to you to the application. Otherwise there's not alot to these. They can be rebuilt at home. Plenty of YouTube vids. Take it apart and identify what bladder you need. There are also rebuild services available. Not much variation other than diameter and external bolt patterns.

 

Some quick Google image searching makes it look like a 1982-84 Nissan Maxima master cylinder/booster. Of course, I could be very, very wrong.

 

Looks like some kind of tag on top of the round vacuum chamber, any useful info there?

 

Power brake booster. The part in front of it is the master cylinder. I don't recognize yours but using the correct terms may help with your search. Good luck!

 

Most, if not all, vacuum boosters require a seal or fat O-ring where the master cylinder mounts into the booster. You may have a ruptured diaphragm in the booster, but that is not very common.
-Donny

 

It’s leaking around the rod.

 

It’s appearing it’s early 80’s. As long as the bolt pattern fits would it be safe to assume exact replacement model is not required?

what are the factors to consider?

 

Not really.

 

Mid-Eighties Nissan Passenger Car, near as I can figure. It's not *that* critical on the booster, it's a single-diaphragm unit, making your life easier by finding one that has the same stud/bolt pattern and pushrod lengths is really the important part.

 

right. That’s not easy and there are no cross references.

 

Meh, take some measurements off yours, and head down to FLAPS, and ask to look at the one for an '85 Sentra, and see if it matches up or not.