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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 08:51
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hahah, I have to ask. In the KE70 I have an 8mm supply line and a 6mm return line, but I was thinking of using the 8mm return line off the charcoal chamber? Is there any use for the charcoal chamber with a 4AGE and a high pressure fuel setup?
Cheers,
Kev.
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Location:
Canberra
Registered:
July 2005
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 09:01
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Charcoal canisters catch fuel vapours. Basically, fuel is a volatile liquid, thus vaporises easily. If you don't catch this vapour, you lose fuel. Apparently, in a vehicle without a charcoal canister, 25% of the hydrocarbon emissions stem from here. Not only does it help save the environment, but you save fuel! You will see that the other hose from the canister connects to the intake, so when the vehicle is running, the fuel vapour is burnt.
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Location:
Campbelltown
Registered:
November 2003
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 09:43
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| tricky wrote on Wed, 21 September 2005 19:01 |
Charcoal canisters catch fuel vapours. Basically, fuel is a volatile liquid, thus vaporises easily. If you don't catch this vapour, you lose fuel. Apparently, in a vehicle without a charcoal canister, 25% of the hydrocarbon emissions stem from here. Not only does it help save the environment, but you save fuel! You will see that the other hose from the canister connects to the intake, so when the vehicle is running, the fuel vapour is burnt.
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Being volatile has nothing to do with it vapourising easily, it vapourises or turns to gas easily because it has a low boiling point. 
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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 10:00
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K thanks for the info!
Anyone got a photo of where exactly to connect the line from the chamber to the intake on a 4age?
Cheers,
Kev.
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 10:21
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| Corona RT142 wrote on Wed, 21 September 2005 19:43 |
Being volatile has nothing to do with it vapourising easily, it vapourises or turns to gas easily because it has a low boiling point.
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are you sure?? sounds like you have said the same thing three times 
volatility is the measure of how volatile something is.
if something is volatile, it readily vapourises.
this is not necessarily because it has a low boiling point, but more to do with having a high vapour pressure..
and vapour pressure increases as temperature gets closer to the boiling point....
metals have low volatility, but take them into space (with low temps) and you have to worrry about metal loss from evaporation
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Location:
brisbane
Registered:
September 2005
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 11:01
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this is sounding too much like my chemistry class...and i come here to get away from mr flemming 
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Location:
Newcastle, Australia
Registered:
March 2005
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 12:36
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Why not just block the line from the fuel tank that goes to the charcoal canister? No fuel vapour loss then
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Location:
Canberra
Registered:
July 2005
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 12:57
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| oldcorollas wrote on Wed, 21 September 2005 20:21 |
| Corona RT142 wrote on Wed, 21 September 2005 19:43 |
Being volatile has nothing to do with it vapourising easily, it vapourises or turns to gas easily because it has a low boiling point.
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are you sure?? sounds like you have said the same thing three times
volatility is the measure of how volatile something is.
if something is volatile, it readily vapourises.
this is not necessarily because it has a low boiling point, but more to do with having a high vapour pressure..
and vapour pressure increases as temperature gets closer to the boiling point....
metals have low volatility, but take them into space (with low temps) and you have to worrry about metal loss from evaporation
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 The T knows what he's talking about! Not only does he spend much time with solvents in organic chemistry, but he's currently studying for fluid dynamics exam in the morning, so I better hope my definitions are up to scratch!
Corona, it sounds like you have been instilled with the common misconception that volatility is the flash point. But maybe not. I dunno. Doesn't matter really 'cos now ya know
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Location:
Canberra
Registered:
July 2005
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 13:00
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bleh. didn't come out the way I wanted. What I meant to say was
"...common misconception that high volatility is low flash point..."
Something I've had to coorect a fair few people on lately.
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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 13:31
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Lol...
| Phrostbyte wrote on Wed, 21 September 2005 20:00 |
K thanks for the info!
Anyone got a photo of where exactly to connect the line from the chamber to the intake on a 4age?
Cheers,
Kev.
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Location:
Tasmania
Registered:
May 2002
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 14:04
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Normaly, you have one rubber hose from the canister to a vacuum point on the intake manifold. This point should be at the throttle, and only have vacuum when the throttle is opened a bit, when a small vacuum "leak" would not make a big difference. If it is just pluged into the manifold - full vacuum, the air "leak" may upset idle.
To better control this some cars (XT130 I think) have a small tube from the canister to the throttle only as a signal to open a bigger tube from canister to main manifold.
Other cars have a electric switch controled by the computer to let air from canister to intake manifold, which will normaly only happen with the throttle opened.
Other cars, like NCP10 Echos, have this computer controlled switch paulsed letting a bit of air through with small throttle openings, and more with full throttle.
The 4A-GE 20valve has a vacuum port under each throttle letting a small amount of vapour from the canister through at all times (via mini restrictor valves and filters). In adition to this, it also has the cpmuter controled valve with lets alot of vapour from the canister to main inlet manifold under cirtain conditions (open throttle).
All cars built for racing that I have seen have the charcole canister, and PCV systems removed. The idea is to not let any unknown gasses be given a chance to stuff with the motor in any way. I simple motor is used only, no vacuum tubes unless realy needed. Just a couple of big breather tubes to a catch can.
In this case, should we block the vapour line (which may preasurise the tank), or leave it venting out?
I can't see why the vapour line can't be used as a return. I havn't heard anything against doing that.
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Location:
Brisbane
Registered:
February 2003
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Location:
Sydney
Registered:
September 2004
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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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Re: What the hell does a charcoal chamber do?!
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Wed, 21 September 2005 16:08
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Cheers for that, but over the last few days I've noticed something... Both my return line and supply line are almost completely blocked off, yet a couple of times I've come to the car, there is fuel absolutely pushing its way out of those lines, and the only way to stop it is to open the cap on the tank and you get a big "WOOSH" sound of all the pressurized vapour being released...
Now you would think that if vapour was going down the line to the canister... how is it that the tank keeps getting pressurized??? I have not blocked it off, it's basically a free exit for vapour, yet it ain't doing anything?
Kev.
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Location:
Brisbane
Registered:
February 2003
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Re: What the hell does a charcoal chamber do?!
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Thu, 22 September 2005 01:55
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sounds like you've swapped the fuel return line with the charcoal-cannister vent line.
they usually dump into what looks like the top of the tank, but if you open the tank up you'll see that the cannister pipe is designed to not get blocked/covered with fuel.
note: the cannister will prevent the tank from dumping fumes when the engine is off - so if you park the nearly-empty car in the sun, turn engine off then come back in an hour the tank will be pressurized to prevent those fumes escaping. If you took the car for a 5 minute drive, you'd find most of that pressure gone as the cannister will have dumped those gasses into the intake manifold.
The filler cap should also have a safety device that limites pressure in the tank - perhaps you have the wrong filler cap as well?
cheers,
Charles.
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Location:
Newcastle, NSW
Registered:
May 2004
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Location:
brisbane
Registered:
September 2005
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Re: What the hell does a charcoal chamber do?!
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Sat, 24 September 2005 03:15
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ive always had this, wondering would u lose fuel that way, coz it isnt going to the cannister and back again?
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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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Re: What the hell does a charcoal chamber do?!
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Sat, 24 September 2005 03:27
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Yeah on my first KE70 the fuel cap had been replaced with a dodgy cheap-o one and if i took a left turn too hard I'd have fuel leaking out the cap... I replaced the cap with one off another KE70 and never had that problem, but always had the pressure when I opened it.. Also with the second KE70 it's been like that since I got it. I can't see much problem with it, the fuel lines are designed for up to about 5-6PSI, and the fumes you lose when you open your fuel cap would probably only be about 10-20ml of petrol, which is just about nothing...
Kev.
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I supported Toymods
Location:
sydney.au
Registered:
August 2002
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Re: What the hell does a charcoal chamber do?!
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Sat, 24 September 2005 13:46
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i dont know about you eggheads and your equations and formulas
but mine goes 'chzzzzzzzzzzzzzzzzzzzzzzzzzzzz' for no good reason even when the car has been off for hours
apparently all the JDM ae86's have this funky feature! hehe
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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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Re: What the hell does a charcoal chamber do?!
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Sat, 24 September 2005 13:54
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Lol yeah my KE70 does that too, and I heard it happen on Sam_Q's ADM AE86 while helping to replace a gearbox, lol almost dropped the gearbox  .
Kev.
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Location:
Newcastle, NSW
Registered:
May 2004
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Re: What the hell does a charcoal chamber do?!
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Sat, 24 September 2005 13:56
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| Phrostbyte wrote on Sat, 24 September 2005 13:27 |
, and the fumes you lose when you open your fuel cap would probably only be about 10-20ml of petrol, which is just about nothing...
Kev.
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the way fuel is, thats like a cent every time u open ur cap  ...in another years time we could be paying $1 for the privilage of opening our caps  lol
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I supported Toymods
Location:
sydney.au
Registered:
August 2002
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Re: What the hell does a charcoal chamber do?!
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Sat, 24 September 2005 13:57
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hahaha funny
i love that sound... hehehehe
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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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Location:
Brisbane
Registered:
February 2003
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Re: What the hell does a charcoal chamber do?!
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Sat, 24 September 2005 14:11
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Strange things.
My fuel system is pressurising, and the tank and been dropped and checked over.
The charcoal canister was removed and the line plugged, I thought this might be part of the problem so today I unplugged it and went for a drive. Got home, smelt fuel and had a look...fuel was running out of the previously plugged charcoal canister line and onto the garage floor!
This has got to be a problem with fuel line plumbing?
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Location:
Canberra
Registered:
July 2005
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Re: What the hell does a charcoal chamber do?!
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Sun, 25 September 2005 02:12
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as said previously by another dude, your return and charcoal lines may be switched.
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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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Re: What the hell does a charcoal chamber do?!
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Sun, 25 September 2005 03:16
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| monkeymajik wrote on Sun, 25 September 2005 00:11 |
Strange things.
My fuel system is pressurising, and the tank and been dropped and checked over.
The charcoal canister was removed and the line plugged, I thought this might be part of the problem so today I unplugged it and went for a drive. Got home, smelt fuel and had a look...fuel was running out of the previously plugged charcoal canister line and onto the garage floor!
This has got to be a problem with fuel line plumbing?
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Nope lol, If the line was plugged then obviously all the fumes have nowhere to go and just built up pressure. When you unplugged it the fumes could easily escape, and without a charcoal chamber to hold the fumes, you're just going to get fuel running out that line.
Your best bet without a charcoal chamber is either, if you have an EFI setup I wouldn't worry about it because the pressure your pump pumps at, would be much more pressure than fumes could create, so just plug the line again. If you do have a carby setup, a breathable fuel cap would be a good idea, but keep in mind you'll lose a bit of fuel from it.
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Location:
Brisbane
Registered:
July 2005
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Re: What the hell does a charcoal chamber do?!
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Sun, 25 September 2005 23:22
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While everyones got charcoal canisters on the top of their minds...Im just about to hook up one on my 2JZ after the retard mechanics managed to loose the old one from my car AND the one that came with the halfcut.
Ive bought one out of a Cressida or something. I was just gonna hook it up to the fuel vent line (or wateva its called) and then splice it into an existing vacuum line on the plennum. (No spare holes I can find).
Now questions time:
How do I know which pipe on the canister it the inlet and outlet?
What happens when my plennum has positive pressure? Wouldnt it be forcing air back into the fuel system?
Do I have to fit some sort of one-way valve anywhere on this system??
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