Vacume lines?

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Debumpered
Posts: 4
Location: Te Puke

Vacume lines?

Post by Debumpered » Sun Sep 25, 2011 3:06 pm

hi i'm wondering if anyone could help me identify where the hell the vacum lines go in the engine bay on a 79 280z have had engine out an didn't label where they came from an went to?

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bernjean
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Post by bernjean » Sun Sep 25, 2011 8:44 pm

Is your car fuel injected, if so I can help. Can take some pics of mine. Just advise.
Bernie Kant
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Debumpered
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Location: Te Puke

Post by Debumpered » Sun Sep 25, 2011 8:55 pm

yip its a fuel injected l28e

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bernjean
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Post by bernjean » Sun Sep 25, 2011 9:10 pm

Okay taking the car to work to get wof tomorrow will take pictures of all the vacuum lines in the engine bay for you
Bernie Kant
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bernjean
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Post by bernjean » Mon Sep 26, 2011 4:26 pm

Here are some pics of my vacuum hoses
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Bernie Kant
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bernjean
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Post by bernjean » Mon Sep 26, 2011 4:41 pm

I think I have this right, main vac line goes from manifold across engine bay to vac bottle, vac bottle has an in and out. The out line goes to two electric valves and is imputed through the firewall to the heater controls.

The valve in the manifold has two outs one goes to this thing that appears to be connected to to the fuel line. (no idea what it does.) The other to the vac bottle.

I have a pic of a hose disconnected, on my car it does nothing.

My car originally had a 2 litre engine, was replaced with a 2.8 and has a combo of 2 litre and 2.8 parts, the throttle body was also changed to a bigger diameter one. So that may change to advance retard set up.

Hope this helps.

If you have disconnected all the hoses at the heater end, GOOD LUCK. Had them out when I did the dash and carefulyl labeled everything, there are a gazillion hose connections there.
Bernie Kant
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djz
Posts: 849
Location: Christchurch

Post by djz » Mon Sep 26, 2011 6:11 pm

Little bit different to factory by the looks of it, but it all works the same!

Usually the FPR is connected to a port closer to the middle of the inlet manifold, the very rear port usually only has two barbs on it if the motor/car was auto to start with, the bigger one is for the kickdown switch if I remember correctly and the other smaller one runs over the engine to the right hand side of the bay.

Once upon a time there was probably a vacuum diagram on the inside of the bonnet, it might be in the Haynes manual too but I don't know where my copy is.

Once you get to the throttle body/charcoal canister tubing that's where I get lost, I pulled most of that stuff out in the first couple of weeks of owning all my Z's.
Nissan 280ZX 2 seater RB26 powered.

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djz
Posts: 849
Location: Christchurch

Post by djz » Mon Sep 26, 2011 6:14 pm

Also I'm pretty sure the metal line built in to the fuel rail is for the EGR valve, you show the hose being disconnected at the front but it's also bunged at the back so won't be doing anything anyway?
Nissan 280ZX 2 seater RB26 powered.

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asyado
Posts: 275
Location: Carterton, Wairarapa

Post by asyado » Mon Sep 26, 2011 7:08 pm

Hi all,
I've mentioned it before, but the time taken with a digital camera and taking plenty of snaps can save alot of heartache if something is going to be apart for along time.
Off the top of my head I think I ended up taking somewhere in the order of 700 hundred + photos of every nut bolt, bracket, bodypanel, hose, wiring loom, fuel lines, carbs, power train and suspension, not to mention all of the hidden stuff up under the dash just before it will part from the firewall.
I have these pic's in four different lots of copies, one set is on the net, the others on disc file, one @ my place, one @ a friends and the other @ a friend who owns his own mechanics business and is Datsun crazy like me.
One might say I'm completely over the top but I have heard of guys losing their only copies of pic's to an unexpected fire @ their place and destroying everything.
When I see all of the stuff I have pulled out of it and it's sitting on the floor of my garage, it can seem alittle daunting thinking of how it goes back together but if I've done my homework right, it will be a case of reverse order, just follow the pic's back in reverse order and things should run fairly smoothly.
I would guess Bernie that the vacuum hose going to the fuel line operates a fuel shutoff valve, no vacuum then no fuel is able to go any further to the injectors as the vacuum would hold open a spring loaded shutoff valve.
That is a logical guess there Bernie, not having seen one myself to view its workings.
I must put a vacuum gauge on a motor one day to see just how many Kpa's one actually produces, anyone here know the value on a Zed?
I hope you will find where all of your lines go with Bernie's help, I'm certain that you will tell straight away if you have missed one.
Nigel aka asyado
Insanity is only one gear change away!!!

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ZMAD
Posts: 657
Location: Tauranga

Post by ZMAD » Mon Sep 26, 2011 7:29 pm

Bernie, I know there should be a valve in the bracket where the vacuum solenoids mount. Your hose goes through to the solenoid with no valve. One of the solenoids does the heater controls and the other aircon controls. My valve failed stopping heater working correctly and replaced with random one to fix. Looks like I'm not the only one to have to trim hoses all the time where they split.
All Nissans are racecars.

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ZMAD
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Location: Tauranga

Post by ZMAD » Mon Sep 26, 2011 7:31 pm

Just noticed the aircon setup. Any chance of more pics to show the rest of setup at front etc.
All Nissans are racecars.

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bernjean
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Post by bernjean » Mon Sep 26, 2011 9:02 pm

You are right about the one way valve, I seem to remember having a problem and finding it wasn't working at all so I removed it and everything seemed to fine so did without it. Funny you should say about trimming the hoses took car to work to get a WOF today and could,t get the air to blow on the front screen, discovered that I had a split end on the hose, slowly getting shorter but still enough for a couple of years trimming I think.
I have removed the carbon canister if I remember correctly they had quite a few lines attached to it. There is still a fuel line that comes up to where it used to be, I have just put a little vent on the top of it. Looks factory except for the small Mitsubishi star on it.
I think you might be seeing the power steering pump, I have fitted power steering and the pump sits in the same place as the 280zx, except mine is all Subaru parts. Am more than happy to take pics will look again when I get the car out of the corner of the garage.
Come along on Saturday and look in person, opps you might not be in Auckland.
Bernie Kant
Club President

Debumpered
Posts: 4
Location: Te Puke

Post by Debumpered » Tue Sep 27, 2011 4:07 pm

cheers guys mayor help.
it was only the engine bay vac lines wasn't keen on unplugging the ones inside the car

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ZMAD
Posts: 657
Location: Tauranga

Post by ZMAD » Tue Sep 27, 2011 4:14 pm

That's right. Way down in Tauranga. I brought a used air con system and found it hard to work out its factory mounting positions. The charcoal cannistor has 3 conections. One to the tank(petrol vapour), one to intake manifold and one to the carb to sense throttle position. The petrol vapour is burnt instead of polluting the atmosphere and helping with fuel economy.
All Nissans are racecars.

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