Skyline’s charcoal canister !

[Rb25orange]

Good day everyone,

I have too many questions, probably thinking from nose right now. 
Having strong fuel fumes burning my nose every day to from work so Need some urgent help-advise from you legend’s.

I am going to keep it sort and straight to start with. I don’t have a personal opinions as yet. But aware of how it works and where what is, but here to see what others have done to resolve it in all directions (legality etc.)

Don’t have charcoal canister, never did.

Was complete project and long road of making things right one after another I guess that’s how it is for everyone. 
 

Anyhow, fuel vent(breather) line is left open in the engine bay. So tank vent to rubber hose to hard line along all other hard lines and open end next to factory fuel filter.

 

Really nasty always sick everyday twice for an hour so please what’s the temporary fix for this, till I gather to do it properly.

That said, is anyone running aftermarket canisters relocated else where other than factory spot. 

Much appreciate all the inputs.

 

Question from own understanding, can I temporarily have it vented at the rear after the rubber hose from vent with a valve or fuel line mesh filter. 
Would that help me not turning up high at work for a while.

[Murray_Calavera]

Is there any reason you can't just pick up a factory one from a wrecker? 

[BK]

6 minutes ago, Murray_Calavera said:

Is there any reason you can't just pick up a factory one from a wrecker? 

Absolutely do this. I run R33 charcoal canisters on the 32s as they are half the size of a 32 one. New they are $300 -$400, 2nd hand $50ish so just get one.

[Rb25orange]

Yea looking into doing that, 

Can I confirm the following please.

 

So canister got 3 lines in and out, 
1) tank vent to canister (in)
2) canister to atmo (out) somewhere down the chassis rail 
3) canister to ? throttle body ? Intake mani ? Don’t t know ? 

 

Edited September 23, 2022 by Rb25orange

[Rb25orange]

1 hour ago, BK said:

 

[BK]

33 minutes ago, Rb25orange said:

Yea looking into doing that, 

Can I confirm the following please.

 

So canister got 3 lines in and out, 
1) tank vent to canister (in)
2) canister to atmo (out) somewhere down the chassis rail 
3) canister to ? throttle body ? Intake mani ? Don’t t know ? 

 

Technically 4.

3 at top, one on bottom. A fresh air vent on bottom is just a hose that can connect to nothing as an atmosphere breather. Top has 3 ports - one to fuel tank vent, one post throttle (boost and vacuum) and one pre throttle (no vacuum, boost only). On RB26 this is at the AAC chamber top front nipple and throttle body cylinder 1 and 2 assembly nipple near stock fuel reg location.

These need to be correctly connected at the canister as there is a diaphragm inbuilt to control operation.

[joshuaho96]

Keep in mind that the bottom fresh air vent is not necessarily just a fresh air vent, it can also vent liquid fuel if you overfill the tank so there is some mechanism on most of these cars to deal with that.

[GTSBoy]

And, just in case this is a Neo - there is an ECU controlled purge solenoid to determined when vacuum is allowed to be passed to the canister, so it won't purge at times when the ECU doesn't want it to.

[TurboTapin]

12 hours ago, BK said:

Technically 4.

3 at top, one on bottom. A fresh air vent on bottom is just a hose that can connect to nothing as an atmosphere breather. Top has 3 ports - one to fuel tank vent, one post throttle (boost and vacuum) and one pre throttle (no vacuum, boost only). On RB26 this is at the AAC chamber top front nipple and throttle body cylinder 1 and 2 assembly nipple near stock fuel reg location.

These need to be correctly connected at the canister as there is a diaphragm inbuilt to control operation.

Always wondered how these worked as I knew they had different part# between turbo and non turbo but look identical and connect to the same areas. I'm presuming on turbo models when there's pressure from throttle body hose, it stops purging. What about non turbo models? 

[BK]

Not sure on the atmo, but would work the same way I would think as the canister diaphragm works of a pressure differential. Throttle open means both pre and post throttle lines have no pressure difference - keeps canistet closed. When the throttle is closed the post throttle line creates a pressure differential in the canister diaphragm because of the vacuum one side and atmosphere pressure the other side - this is what opens the canister.

The only way I could see the atmo vs turbo canisters being different is if the canister diaphragm is not able to handle positive pressure, meaning turbo version would have to have an added check valve in it to stop boost. This is speculation as I weren't aware they were different at all.

[Rb25orange]

10 hours ago, GTSBoy said:

And, just in case this is a Neo - there is an ECU controlled purge solenoid to determined when vacuum is allowed to be passed to the canister, so it won't purge at times when the ECU doesn't want it to.

Non neo, assuming I won’t need a purge solenoid in my case ?

[Rb25orange]

13 hours ago, joshuaho96 said:

Keep in mind that the bottom fresh air vent is not necessarily just a fresh air vent, it can also vent liquid fuel if you overfill the tank so there is some mechanism on most of these cars to deal with that.

Will do, much appreciate the diagrams man been looking everywhere. 
Its time to get a copy of engine manual I guess. Need bunch of things done right.

[Rb25orange]

22 hours ago, BK said:

Technically 4.

3 at top, one on bottom. A fresh air vent on bottom is just a hose that can connect to nothing as an atmosphere breather. Top has 3 ports - one to fuel tank vent, one post throttle (boost and vacuum) and one pre throttle (no vacuum, boost only). On RB26 this is at the AAC chamber top front nipple and throttle body cylinder 1 and 2 assembly nipple near stock fuel reg location.

These need to be correctly connected at the canister as there is a diaphragm inbuilt to control operation.

Awesome, 

Does this also mean I can just fit any charcoal canister that works similar ? Probably will end up going to wreckers, if I don’t find Nissan one close by. 

Any chance s13 one works ?

or any other Nissan/Datsun one that be easy to find. I don’t t care about looks. 
 

 

 

[Rb25orange]

2 hours ago, Rb25orange said:

Non neo, assuming I won’t need a purge solenoid in my case ?

Any benefits of running solenoid ? While I am at it. 
 

[Rb25orange]

Just now, Rb25orange said:

Any benefits of running solenoid ? While I am at it. 
 

@GTSBoy 
sorry I am new here

[BK]

Buy this - $80. These guys are in Melbourne and are pretty good to deal with.

https://jpjdm.com/shop/index.php?id_product=3332&rewrite=nissan-skyline-r33-s2-gtst-charcoal-canister-14950-21u00&controller=product

[GTSBoy]

54 minutes ago, Rb25orange said:

@GTSBoy 
sorry I am new here

Nah. Only need it if the ECU wants it. Non-Neo has no care.

[TurboTapin]

On 9/23/2022 at 10:11 PM, BK said:

Not sure on the atmo, but would work the same way I would think as the canister diaphragm works of a pressure differential. Throttle open means both pre and post throttle lines have no pressure difference - keeps canistet closed. When the throttle is closed the post throttle line creates a pressure differential in the canister diaphragm because of the vacuum one side and atmosphere pressure the other side - this is what opens the canister.

The only way I could see the atmo vs turbo canisters being different is if the canister diaphragm is not able to handle positive pressure, meaning turbo version would have to have an added check valve in it to stop boost. This is speculation as I weren't aware they were different at all.

So I decided to test the canister and figure out exactly how it works.

The top port marked "VC" that originally went to the throttle body does not react at all to pressure. It reacts to vacuum.

When there's more vacuum on the VC port then there is on the purge port, it opens allowing a vacuum on the charcoal to regen the charcoal. Without this, the charcoal would become saturated from the fuel vapor going through it and into the bottom port that connects to the frame rail. 

With this being said, unless you pipe VC pre throttle and purge post throttle I believe your charcoal will saturate rendering the canister useless. I avoided this and the concern that the canister would not handle 35+PSI and decided to remove it and pipe the tank vent into the frame rail. 

In theory as you said with differential it would also open, but you require vacuum on the purge line to suck in fuel vapor so that rules out any situation outside of vacuum. 

[GTSBoy]

When it comes to boost..... think check valve.

The Neo uses an ECU solenoid to dictate when to purge, and this keeps boost away from the canister as a side effect.

[TurboTapin]

1 hour ago, GTSBoy said:

When it comes to boost..... think check valve.

The Neo uses an ECU solenoid to dictate when to purge, and this keeps boost away from the canister as a side effect.

I have not seen a check valve on the "Signal VC" line anywhere on an R32/33. The positive pressure just pushes down on the diaphragm, closing the purge port.  As for newer cars that use a purge solenoid, there's no need for the vc port as the ecu controls when to purge. 

We might be saying the same thing.