MR2 Roadster Owners Club

The Workshop => Maintenance, Problems & Troubleshooting => Topic started by: m1tch on July 16, 2017, 21:47

Title: Charcoal canister removal
Post by: m1tch on July 16, 2017, 21:47
Hi all,

Just wondering what I need to do to remove the charcoal canister, its 14 years old and I am pretty sure its well past it, looking to remove it to clean up the engine bay a bit and lose some weight, I will look to run breathers on the cam cover, I am guessing that there is a fuel tank vent somewhere as well.

Just wondering how best to go about removing it and plumbing the pipework in.
Title: Re: Charcoal canister removal
Post by: ilovejapcrap on July 16, 2017, 22:23
the fuel tank vents into this I think
Title: Re: Charcoal canister removal
Post by: m1tch on July 17, 2017, 07:47
Yeah the canister should have inputs for the PCV breather system from the cam cover as well as the fuel tank vent - just wondering what the usual reroute is when removing the canister, on the MX5 you can usually loop the lines or vent to atmosphere.
Title: Re: Charcoal canister removal
Post by: Carolyn on July 17, 2017, 08:02
The canister has a vacuum input that comes (via the solenoid valve mounted on the big rubber inlet tube) from the inlet manifold.  If you remove the canister , remove the solenoid and block off the tube that goes to it from the engine.  Don't block the other tube to the canister as that is the breather for the petrol tank.
Title: Re: Charcoal canister removal
Post by: m1tch on July 17, 2017, 08:06
Quote from: "Carolyn"The canister has a vacuum input that comes (via the solenoid valve mounted on the big rubber inlet tube) from the inlet manifold.  If you remove the canister , remove the solenoid and block off the tube that goes to it from the engine.  Don't block the other tube to the canister as that is the breather for the petrol tank.

Thanks Carolyn, I will check the pipework in the engine bay, I could see the solenoid and various pipework around the engine bay but just needed to check how best to go about it - will probably remove the setup tonight or when I fit the new induction kit.
Title: Re: Charcoal canister removal
Post by: shnazzle on July 17, 2017, 09:38
Or extend the breather from the fuel tank to the rear bumper,add a check valve and put the solenoid on with a 12v feed with a button.
Then u kan makez da flamez and be cool like the all the cool kidz. In it.



...don't do this..

Sent from my ONEPLUS A5000 using Tapatalk
Title: Re: Charcoal canister removal
Post by: Topdownman on July 17, 2017, 10:00
Quote from: "shnazzle"Or extend the breather from the fuel tank to the rear bumper,add a check valve and put the solenoid on with a 12v feed with a button.
Then u kan makez da flamez and be cool like the all the cool kidz. In it.



...don't do this..

Sent from my ONEPLUS A5000 using Tapatalk

He gives and he taketh away....
Title: Re: Charcoal canister removal
Post by: m1tch on July 17, 2017, 12:10
Quote from: "shnazzle"Or extend the breather from the fuel tank to the rear bumper,add a check valve and put the solenoid on with a 12v feed with a button.
Then u kan makez da flamez and be cool like the all the cool kidz. In it.



...don't do this..

Sent from my ONEPLUS A5000 using Tapatalk

ZOMGZ KOOLZ, Will do dis!

Maybe not  s:P :P s:P

Will look to remove and reroute/blank the various parts of the system, will also be interesting to see how much the setup weighs as I know there is the canister as well as some hardline as well.
Title: Re: Charcoal canister removal
Post by: SteveJ on July 17, 2017, 16:33
IIRC, only the US cars have a charcoal canister and it is mounted underneath the storage bins. The unit in the engine bay is a trap to prevent fuel being drawn into the intake when the tank is filled up the neck and the solenoid opens.

(https://www.comtech-it.com/pics/evap.png)

[edit] You'll save more weight by not having a bacon-batch (or at least recycling it  s;) ;) s;)  ) before doing a 1/4mile run than you will removing the canister in the engine bay. [/edit]
Title: Re: Charcoal canister removal
Post by: m1tch on July 17, 2017, 17:01
Quote from: "SteveJ"IIRC, only the US cars have a charcoal canister and it is mounted underneath the storage bins. The unit in the engine bay is a trap to prevent fuel being drawn into the intake when the tank is filled up the neck and the solenoid opens.

(https://www.comtech-it.com/pics/evap.png)

[edit] You'll save more weight by not having a bacon-batch (or at least recycling it  s;) ;) s;)  ) before doing a 1/4mile run than you will removing the canister in the engine bay. [/edit]

Ah, so its not a charcoal canister, but its still part of the emissions system, will be careful when removing and plugging the pipework etc, more interested to see how much the setup weighs though, it does all add up, driver weight will also be reduced further.
Title: Re: Charcoal canister removal
Post by: m1tch on August 15, 2017, 12:53
After seeing leethesparky remove the canister from the side of the engine bay I thought I would also look into it, it would seem I could simply connect up a line between the tank breather pipe and the solenoid. However after pulling the canister out (it weights around 750g) I noticed that one side is actually a cap that can be removed meaning that its already venting gasses into the engine bay owing to having just a foam seal rather than an air tight seal.

Would it be ok to remove the whole setup between the canister and the intake including the solenoid and simply vent the tank to atmosphere - maybe run a line to behind the rear light? I would need to block off the throttlebody as well to prevent an air leak but it would tidy eveything up.
Title: Re: Charcoal canister removal
Post by: Carolyn on August 15, 2017, 14:27
Many have done just that.  Perhaps leave the hose from the throttle body and plug that?  Never know when you might want the vacuum.
Title: Re: Charcoal canister removal
Post by: m1tch on August 15, 2017, 16:06
Quote from: "Carolyn"Many have done just that.  Perhaps leave the hose from the throttle body and plug that?  Never know when you might want the vacuum.

Thanks for that, I will look to do the mod tonight then and see how much it all comes to - always best to remove weight off the rear now the frunk is empty! Will remove the canister, hard line and solenoid and then plug the pipe to use as a vacuum source, will then run a pipe from the tank vent pipe to the rear.
Title: Re: Charcoal canister removal
Post by: ChrisGB on August 16, 2017, 07:26
An open tank vent will leave your car smelling strongly of fuel, I'd suggest plumbing in something like this:

https://www.newton-equipment.com/tank-vent-valves-inline-tank-valve-model-tpv8.html

Makes a big difference!
Title: Re: Charcoal canister removal
Post by: m1tch on August 16, 2017, 07:38
Quote from: "ChrisGB"An open tank vent will leave your car smelling strongly of fuel, I'd suggest plumbing in something like this:

 m https://www.newton-equipment.com/tank-v ... -tpv8.html (https://www.newton-equipment.com/tank-vent-valves-inline-tank-valve-model-tpv8.html) m

Makes a big difference!

Ah, am I correct to say that those are 1 way valves which then open when the tank gets to a certain pressure?
Title: Re: Charcoal canister removal
Post by: ChrisGB on August 16, 2017, 07:48
Sort of, it opens to prevent vacuum in the tank when you are using fuel and it vents pressure in the tank with temperature changes.
Title: Re: Charcoal canister removal
Post by: m1tch on August 16, 2017, 07:51
Quote from: "ChrisGB"Sort of, it opens to prevent vacuum in the tank when you are using fuel and it vents pressure in the tank with temperature changes.

Cool, will check the diameter of the vent pipework later tonight - would something like those bike tank breather valves work? Or could I simply use a small inline fuel filter which will allow the tank to vent but reduce the fuel vapor smell etc?
Title: Re: Charcoal canister removal
Post by: ChrisGB on August 16, 2017, 07:57
Quote from: "m1tch"
Quote from: "ChrisGB"Sort of, it opens to prevent vacuum in the tank when you are using fuel and it vents pressure in the tank with temperature changes.

Cool, will check the diameter of the vent pipework later tonight - would something like those bike tank breather valves work?

Possibly, I always ran bikes open breather and anti spill valve.
Title: Re: Charcoal canister removal
Post by: m1tch on August 16, 2017, 12:36
Quote from: "ChrisGB"
Quote from: "m1tch"
Quote from: "ChrisGB"Sort of, it opens to prevent vacuum in the tank when you are using fuel and it vents pressure in the tank with temperature changes.

Cool, will check the diameter of the vent pipework later tonight - would something like those bike tank breather valves work?

Possibly, I always ran bikes open breather and anti spill valve.

Cool, they are only a few £s so will try that first and see what its like.
Title: Re: Charcoal canister removal
Post by: shnazzle on August 16, 2017, 14:29
at what point will the VSV purge fuel fumes into the intake? Just on start up? On cold? What are the negative effects to removing this system.
Also, will the removal of the solenoid cause a CEL, as it is ECU-driven?
Title: Re: Charcoal canister removal
Post by: m1tch on August 16, 2017, 16:15
Quote from: "shnazzle"at what point will the VSV purge fuel fumes into the intake? Just on start up? On cold? What are the negative effects to removing this system.
Also, will the removal of the solenoid cause a CEL, as it is ECU-driven?

I am guessing that it would purge when on cruise as adding in fuel rich vapour would cause issues if the engine is under load etc, I was expecting multiple lines going into that tank but it seems its only for the tank vent, I doubt that after 14 years any active ingredient in the tank is doing anything.

I am guessing it might through a CEL, I will run with it unplugged next time and see if it throws something, guessing it would usually flag that something isn't working - I guess it could simply be kept connected for the ECU to be happy its still attached.
Title: Re: Charcoal canister removal
Post by: shnazzle on August 17, 2017, 20:18
I'll get thus one post-pay-day

http://www.demon-tweeks.co.uk/Product.do?method=view&n=1546&p=23336&d=124&c=4&l=2&utm_source=Google&utm_medium=Base&utm_campaign=Fuel%20Tank%20Vent%20Valves&gclid=CjwKCAjw_dTMBRBHEiwApIzn_N2Le9aQ4K2CiI_3kkSq3ZOotBMlfaZbFiVcE-92kFk4brb0XC_qJBoC3mcQAvD_BwE
Title: Re: Charcoal canister removal
Post by: ChrisGB on August 17, 2017, 21:58
Quote from: "shnazzle"I'll get thus one post-pay-day

http://www.demon-tweeks.co.uk/Product.do?method=view&n=1546&p=23336&d=124&c=4&l=2&utm_source=Google&utm_medium=Base&utm_campaign=Fuel%20Tank%20Vent%20Valves&gclid=CjwKCAjw_dTMBRBHEiwApIzn_N2Le9aQ4K2CiI_3kkSq3ZOotBMlfaZbFiVcE-92kFk4brb0XC_qJBoC3mcQAvD_BwE

Quite pricey, Merlin Motorsport have them for less. Cannot remember where I bought mine, it was a company recommend by Newton Equipment and it was about £35.
Title: Re: Charcoal canister removal
Post by: shnazzle on August 17, 2017, 22:12
As mentioned on the what did you do thread, it seems there are a few holes in the removal of this.

Fuel vapours, fuel pushed up by pressure, collapsing tanks, etc etc. P0446 code for the evap system if disconnected...
All seems a bit of a faf for the sake of a tidier engine bay
Title: Re: Charcoal canister removal
Post by: ChrisGB on August 17, 2017, 22:19
Have to say, I wouldn't remove it without good reason.
Title: Re: Charcoal canister removal
Post by: shnazzle on August 17, 2017, 22:36
Still tempted. But, easier to just take the canister off when/if I need to be at my aux belt
Title: Re: Charcoal canister removal
Post by: M.R. on August 23, 2017, 21:49
I took charcoal canister off about 3 years ago. Solenoid is also gone. It vents in to atmosphere thru small moped gas filter. Just to prevent possible dirt from going in to hose and tank. Plug in intake instead hose from solenoid. No idea about possible CEL since I have PFC.
Title: Re: Charcoal canister removal
Post by: m1tch on August 24, 2017, 07:25
I have just taken the canister out and put one of the bike 2 way tank breathers at the end, will see how it goes.
Title: Re: Charcoal canister removal
Post by: ilovejapcrap on August 25, 2017, 08:52
Pictures please
Title: Re: Charcoal canister removal
Post by: m1tch on August 29, 2017, 12:28
Quote from: "ilovejapcrap"Pictures please

Will take a photo tonight, drove it around a bit yesterday with no issue, no smell of fuel either - still have the solenoid connected but am running a PFC so might not actuate as per the stock ECU.
Title: Re: Charcoal canister removal
Post by: m1tch on September 19, 2017, 12:30
Quick update on this - not taken a photo yet but its a very simple setup, have driven the car around a bit, there isn't a smell of petrol that I can tell and there is no pressure build up in the tank (I specifically removed the filler cap to check).