Looking for a brake booster

[Alex 240Z]

Motorsports Auto @ $150 is the most expensive for the rebuilt Brake Booster and they want $75 core plus shipping while VB is a little cheaper @ $130 and they want a $25 core charge plus shipping. I can get a new Brake Booster for $112 shipped at my local parts dealer. Now this probably sounds like a no brainer but if I want to keep my car as stock as possible should I go with Motorsports or VB and is a 71 and 72 Brake Booster interchange able cause I do have a four year old booster that was put in new in my 72 !!! How hard is the job of replacing the Brake Booster yourself on a wrench of 1-10 !!! I know this is kind of wordy so thanks for any help in advance !!!! I know Bambikiller will eat me up on this !!!!!

[Dans240z]

Is the master cylinder the same on all 240s? I think that the one on my 73 is different than the one on my 72, but I am not really sure.

Oh, just saw your post John. Yeah, so I guess there is a difference. What is the difference?

[LanceM]

The MC's are all the same, the boosters are different, though I would think a 73 would work on earlier models, it is just larger but not as large as the zx models.

[Bambikiller240]

Is the master cylinder the same on all 240s?

No, the Master Brake Cylinders on all 240Z's are NOT the same.

70-71 used one type, and 72-76 used a different type. The reservoirs (and valving inside the MBC) for the Front and Rear brake circuits are reversed (from the earlier version) on the 72-76 version.

If someone switches to the newer version, they must carefully rebend the fluid lines that connect to the MBC to make sure the correct reservior (and valving inside the MBC) services the correct circuit. The Front Calipers need more fluid (relative to the RWC) to operate. It is important for proper brake function.

[Alex 240Z]

Thanks Bambikiller240 you have definetly clarified it and today I ordered the Brake booster and Master cylinder both remanufactured $100 for Brake booster and $41.00 for Master cylinder plus ups ground shipping from my local auto parts store it will take a week but for the price it is ok with me !!!!

[ZSaint]

Wait a minute... I am putting a 15/16 BMC from a 79 ZX onto my '71 240. I hooked up the lines for my 4-wheel disk brakes. Are you telling me that this BMC is reversed? Or, are the 79's and the 71's the same?

[Bambikiller240]

Look at your 71 BMC, and compare the location of the larger Reservoir to the Larger Reservoir on the 79 BMC. If they are different........

On the 71 that I previously owned, and according to MSA's catalog, the 70-71 MBC would be different the ones used from 72 onward.

For a 72-76 BMC, The LARGER reservoir should supply the front calipers. I've never even seen a ZX BMC so I can't tell you anything about it, but I would think that it would follow the convention of the 72-76, 77, and 78 BMC's

[zamog]

Brake Booster ...installed :y:

Electronic Ignition...installed :y:

Car runs great, stops great

[ZSaint]

I checked and you are correct. ('71 BMC converted to a 79 ZX BMC) The MC's are reversed. I will need to hook up my lines to the correct cylinder outlet. Thank you for this info.

[Bambikiller240]

Better to find out now than when you first need to STOMP on the brakes.

[ZSaint]

I wonder why they designed these MC differently? Anyone have an idea? It doesn't make sense to make this kind of change.

[SledZ]

I took apart my booster to see what I could repair and had no problems getting it back together and running. You will need to make a "tool" to unscrew the 2 pieces and I made mine out of a piece of wood and drilled holes to match the 4 bolts and held the other end in my vice.

My seal around the shaft is corroded and did not seal well and it does hiss sometimes so I bought a booster from VB and swapped the seal to my original because the one from VB had a different vacuum nipple. I'll attach a picture I took of it apart.

You can see the round seal that goes on the end of the rod, that is what falls off causes the booster to fail.

Happened to me when I pushed the brake in and didnt have the MC installed, so I just glued it back on with a dab of rubber cement to hold it while I put it back together.