Get rid of the vacuum system ?

[blaiz]

I don't really know were to post this message I'm sorry... so I'll doit there.

Hi,

I'm Blaise and I live in south-west France. I'm restoring a 75' 280Z and I'd like to know somthing.

Can I throw all the vacuum system to the bin? :nervous: I'm going to try and explain my situation.

- I don't have (and don't want) any air conditionner system (actually all I have of the A/C is a sticker under the bonnet... )

- I wan't to keep the heating system (silly but not mad )

- I don't have any carbon canister (and don't specially wan't to buy one, I'm not selfish, I'm just a studant...).

- I've got the Magnet Vacuum Valve and the vacuum accumulator tank but there were unpluged when I got the car and have no idea of where they have to be pluged.

- I want to take off from the car these last two parts because I want a light aspect around my engine.

I've got the Haynes but can't find anything about this vacuum system on 280Z.

Can I take all this off?

Will it modify the engine performances?

Will it modify the petrol consumption?

Will it be as environmental friendly as before?

Thanks in advance for your help.

[TomoHawk]

The vacuum system controls the spark timing advance through the distributor, and it is needed to make the air control doors for your heater system move.

If you just pull the hoses off, you will lose vacuum from the intake system, and the engine will not run as efficiently as it could You would find good information about the vacuum system for the ventilation system and for the engine in the factory service books..

[beandip]

What you are asking it seems is the hoses that connect to the emissions equipment , correct? Not the ignition . I am a 240 guy and cannot help with this part of your engine. The problem here is that there are sensors that control various things like timing and fuel mixture. I am Sure that some one versed in your year of Z will step up with the information you need . If not remember my name and send me a PM. I know someone that can help but he is difficult to contact. All the best .

[TomoHawk]

He is asking about the vacuum lines in general; post- a/c removal.

There are three that go to emmissions devices; the EGR, carbon canister, and the BCDD. There is one line for the fuel pressure regulator, one for the distributor, one for the transmission, and one for the ventilation system. The latter three are fairly important for the proper functioning of the engine & transmission (except the heater line.)

[sblake01]

If you plug the areas that dealt only with the A/C, you shouldn't have a problem. At least, that's what I think your're talking about. There is no vacuum line to the transmission unless you have an automatic. However, not having a carbon cannister will have an effect on the emissions control system.

[blaiz]

First thanks for all your answers.

In my first message I talked about two different problems actually. I'm sorry but it's muddled up in my mind but it's getting better. This is maybe why you were wondering what I was asking for...

The first thing was about the carbon canister and more generaly the vapor system. Obviously I don't have any.

The second thing was about the vacuum system. I wan't to take off all the parts I can without turning down my engine performances (the heating system has to stay there)

I join a photofraph of my engine (not running, don't panic ) and a scheme of the vacuum system. It might be easier if we use the same words (those on the scheme) and if we wright on these two papers.

I have a manual gearbox.

[blaiz]

... However, not having a carbon cannister will have an effect on the emissions control system.

What is the emissions control system? What effect will it have on it?

I'm doing what I can with my english... thanks for using simple words and even better : drawings

[sblake01]

Connect the line "S" to the check valve as shown by the black line I added to your scheme and remove everything in the shaded area. That will eliminate the A/C part of the vacuum system and leave your vent door controls intact. As far as the vapor sytem is concrned, I wouldn't remove that.

[sblake01]

Here's a scan of the vapor system. If you're missing parts of that, those fumes have to go somewhere.

[blaiz]

Connect the line "S" to the check valve as shown by the black line I added to your scheme and remove everything in the shaded area. That will eliminate the A/C part of the vacuum system and leave your vent door controls intact.

I wonder if the vacuum tank is not usefull as a buffer zone (no man's land...sorry I don't exactly know how to translate the french word "tampon" which can meen a lot of things...).

And if you remove the "magnet valve vacuum source", this means the "vacuum connector" is always connected to the heater system (right part of the scheme). Doesn't this matters? What controles this magnet valve exactly? When does it opens or shuts?

Last question: can you show me (on the photograph of my engine or on an other one) what is the check valve?

Thanks a lot. Your are realy helpfull

[sblake01]

The magnet valves and vacuum tank are part of the fast idle control system. That raises the engine idle speed when the air conditioning is on. You won't need them if you don't have a/c. I don't see the check valve in the picture of your engine. It's a round plastic one way valve with an inlet and outlet. Vacuum will only pass through it in one direction. Looks like a few things are misssing/disconnected on your engine.

[blaiz]

The magnet valves and vacuum tank are part of the fast idle control system. That raises the engine idle speed when the air conditioning is on. You won't need them if you don't have a/c. I don't see the check valve in the picture of your engine. It's a round plastic one way valve with an inlet and outlet. Vacuum will only pass through it in one direction.

Okay. Wonderfull !!

Looks like a few things are misssing/disconnected on your engine.

Yes, defenetly... but it's not running for the moment. My Z is in complet restoration for the moment.

I wanted to know about all this stuff we talked about so that I knew if I could or not remove the metal parts (part of the body) that were necessary to hold the parts that I know now I'm going to remove.

Not very clear... I'm a bit tired... Hope you understood...