1984 911 fuel evaporative system-Need help!

ttucker6 · 09:49 PM

Hello,

I installed a 3.2L engine in my 1977 911S and because of the engine change, I had to visit a referee smog center in CA. My tailpipe emissions were outstanding but I failed due to my fuel evaporative system. The '77 system used the air pump to draw the fuel vapor through the charcoal cannister and then ultimately into the intake mainfold. The air pump is now gone. I'm trying to find someone with a 1984 set-up so I can pick his/her brain and see how the two lines coming out of the charcoal cannister get connected to vacuum or the intake manifold. I have a schematic that seems to indicate that only one line goes directly to the intake manifold (I just don't know where?). It may be easier if I could find someone in the South Bay with a 1984 911 Carrera so I could check it out myself. Thanks for any information at all! I really appreciate any help in this matter...I miss driving my car and it's currently NOT registered!
Thanks again,
Tom

HarryD · 03-09-2004, 10:30 PM

This is the basic layout of all of the systems:

The motor fan shroud has a hole to supply air to the cannister and it vents to the air box.

ttucker6 · 03-10-2004, 12:24 PM

Harry,
Thanks for the quick response, I appreciate it. I have this schematic from my '77 workshop manuals. I also have a 1984 schematic which is slightly different (1 line to air filter). I just don't see where the lines actually go? There are no empty vacuum ports near the fan shroud and if there is one near the air filter/intake, I can't find it.
Thanks again,
Tom

ttucker6 · 03-14-2004, 10:15 PM

Hello,

I've been unsuccessful regarding my fuel evaporative system question so I'm trying a different approach. Is there anyone in the South Bay with an 84 or 85 Carrera willing to let me take a look at how your fuel evaporative system is connected? It would just require me to look at your engine bay for about 5 minutes. It would really help me out.

Thanks,
Tom

project 911 · project 911's Garage

Tom-
I have an older model, but on mine one line goes to a small tube that just goes through the fan shroud (in the center directly behind the fan). The other connected to the air cleaner housing. Neither actually hooked to any vacuum ports. Although I guess you could call the air cleaner a vacuum source. Most people just unhook the whole thing.

RickM · RickM's Garage

Tom,

What do you want to look at...specifically? I'll look at my '85 and take pics if you'd like.

Dan Owens · 03-16-2004, 07:51 AM

Tom,

If I'm not mistaken the line goes to the back of the plastic air filter box just before the AFM. There should be a plastic nipple that it attaches to.

ttucker6 · 03-16-2004, 01:46 PM

Damn, thanks guys (Steve B., RickM, and Dan O). Three quick responses. I wish I could unhook it Steve. Thanks anyway regarding the pictures Rick, I found the nipple behind the air intake box. You were right Dan. That's what I'll do. I have two lines so I'll run one to the air box nipple fitting and plug the other one (per the schematic). Thanks again!
Tom

worn · worn's Garage

Resurectig an old thread. I have a carrera 3.2 that i am attaching to a 914. The car has a charcoal system but for the life of me i dont see a place in the fan cowl for the pressure hose shown in the diagram. Maybe i should go dig the 911 out of very cold storage. Any hints would be welcome.

Hunt3R · Hunt3R's Garage

The above diagram is for SC's, this is the 3.2 evap system diagram (although the airbox still looks like an SC airbox here):

The evaporation chamber is in the driver's front wheel well and the line runs to carbon canister in the passenger rear wheel well. The carbon canister has a line to vent to fresh air there, and then it has a line that runs thru the Wheel well into the engine bay and plugs into the back of the 3.2 air box behind the air filter. There is no hose to the fan cowl like on earlier models.