Booster & MC compatibility

[Zed Head]

49 minutes ago, 240z70 said:

ANOTHER QUESTION:  The brake indicator light is always on on the tac. I have not been able to shut it off.  I checked the handbrake switch and it works, and there is no wire connected to the distribution  block on the firewall.  That is the only two connections that the light is supposed to have... Ideas?

The two switches just complete the path to ground for the light.  The wire that goes to the warning light switch is probably shorted to ground somewhere.  You'll have to find it.

It's not a distribution block, it's just a switch.

[Tirnipgreen]

2 hours ago, Yarb said:

Here’s what happened in my situation. I was having the same issue’s similar to what you’re experiencing. Without getting into great detail. I changed out the booster check valve in the midst of going down the rabbit hole. Come to find out I had installed the new check valve backwards. There is an arrow on the valve. I had it pointing in the wrong direction where I was not getting any assist from the booster.

 

So which direction should the arrow point...?

[Yarb]

Towards the intake

[Yarb]

Ok, I’m getting a little confused on whose thread this is and are we working on a 240 or 280? The information I’ve given is related to a 1978 280z. 

[Terrapin Z]

@Yarb The OP has a 70 240Z but with a F54 280 engine. So sort of both. 

I think he has swapped in a 280 booster and M/C but is having issues. 

@240z70 They did change the M/C around as to F and R so make sure your lines are correct. 

The check valve is one way, but it sounds like you had it on correctly with the woosh, of air when disconnecting. 

[Tirnipgreen]

On 5/24/2023 at 3:28 PM, Yarb said:

Ok, I’m getting a little confused on whose thread this is and are we working on a 240 or 280? The information I’ve given is related to a 1978 280z. 

Turned mine around and what do you know...BRAKES...!

Thanks...!

[Yarb]

How about that!!! Finally a contribution to the forum that has not been mentioned. @Captain Obvioushad a great deal to do with digging me out of that rabbit hole. Glad you got her fixed!!!

[Captain Obvious]

Glad I could indirectly help!

11 hours ago, Yarb said:

digging me out of that rabbit hole

Occam's Razor!   

[240z70]

First of all, thank you all for your input.  To clarify my specs:

11/69 240Z vin in the 300's

1982 F-54 280zx turbo block

MN-47 high quench head.

NA with 2 SU carbs revamped by Ztherapy

Pertronix Electric Ignition and hi volt FLAME coil

Low speed/High Torque starter.

6-3-2-1x2.5inch headers to muffler to 2x2inch dual side exaust.

Super Light weight flywheel

Stage II clutch

Borg Warner T-5 5-speed transmission from 1982 ZX turbo car

R180  3.364 rear end

Panasport "For Racing Only" super light weight rims with 215/60-R15 tires

4-Core aluminum radiator.

16.9 gal  custom aluminum tank.

 

 

 Brakes: Original front disks and back drums.

Master Cylinder: 15/16 

Booster 7" Dual Diaphragm (and yes i did have to make new holes to attach it)

 

So this is the scenario issues that were mentioned above.

• Brake booster and appropriate master cylinder potential replacements due to very hard brakes with current system.  Thinking about going original design but cant find them.
• Brake light on speedometer always on but not connected to the switch on the firewall
• Another issue that just came up this weekend is that the throttle rod from the accelerator to the pedal came out of the plastic round ball joint on the engine side.  Looking for a new one.

Anyway, as always, any info, suggestions or comments are greatly appreciated even if it does not directly apply, so thank you all for your input.

[w3wilkes]

On the brake light on the speedo, have you checked the emergency brake switch? It may have a broken plunger switch.