Finally! Where to source a vented gas cap!

[MarkIII4Me]

Many have wanted to remove the charcoal canister. The easiest way to deal with the fuel vapors is to simply cap off the line and install a vented gas cap, but it doesn't seem like they make any for our cars. It's been asked many times, but I've never seen it answered. Where can I find a vented gas cap?


Solution:

Go to your local Walmart (or anywhere that carries Stant gas caps) and buy yourself a cheap #11819 pre-venting gas cap (fits perfect).

Then just drill out the piece that pivots on the spring (the vent stopper). Simple as that. I decided to drill down a little further and expand the actual venting hole to allow the cap to vent faster. Probably doesn't need to be done, but couldn't hurt.

For those of you looking for a vented cap that needs no modification; sorry, don't know what to tell you. But if you can't drill out a little piece of plastic then you should probably just get outta the game :biglaugh:

 

[pogoism9]

....and hope your fuel system can stay pressurized

 

[adampecush]

you do realize pretty much any charcoal cannister will work on our cars...it doesn't have to be the ugly black round one. Several manufacturers make canisters that are mounted near the fuel tank as well if you are worried about asthetics.

 

[MarkIII4Me]

....and hope your fuel system can stay pressurized

I wasn't aware the gas tank needed pressure, as the fuel pump and regulator provide pressure for the fuel system. Many have vented their gas tanks to atmosphere without any issues (other than destroying the environment).

http://www.supramania.com/forums/showthread.php?t=12213&highlight=catch+removal

 

[MarkIII4Me]

you do realize pretty much any charcoal cannister will work on our cars...it doesn't have to be the ugly black round one. Several manufacturers make canisters that are mounted near the fuel tank as well if you are worried about asthetics.

There are many reasons why people want to remove the CC. As for myself, I didn't feel like installing my rusted cc and brackets when reinstalling everything in the engine bay. Sure if you look hard enough, dish out the dough, and have the ability to fabricate brackets you can purchase alternative canisters with a smaller footprint than the OEM's. However, I've found the capped off line and vented cap seem to be the quickest, cheapest, and best looking option I've come across so far.

 

[Doward]

Enjoy putting your fuel pump under even more work.

 

[Justin727]

Run an external. In tank is for the weak

 

[supraguru05]

if you remove the CC you need a 2 psi check. I purchased one that is used for brakes and am going to install it soon. It seems pretty stiff but it should keep pressure in the tank to help the walbro out

 

[IJ.]

:nono:

 

[jdub]

You need the pressure in the tank to prevent pump cavitation...2 psi is correct.

I wasn't aware the gas tank needed pressure, as the fuel pump and regulator provide pressure for the fuel system. Many have vented their gas tanks to atmosphere without any issues (other than destroying the environment).

However, I've found the capped off line and vented cap seem to be the quickest, cheapest, and best looking option I've come across so far.

Regardless of how "many" have done it...you can't say there are no issues. This kind of thing rears it's ugly head at times when you don't expect and is usually blamed on something else. Like guys that suddently go lean at high RPM and detonate...all because you decide to take "quickest, cheapest, and best looking option"? Give me a break...especially when you have no clue what the CC does (in addition to controlling evap emissions). A JDM cannister mounted under the fender well works great, is cheap, and keeps the system working as designed.

Frankly, putting a vented gas cap on this car is a stupid thing to do.

 

[MarkIII4Me]

You need the pressure in the tank to prevent pump cavitation...2 psi is correct.

Ah, good to know. I'm glad you mentioned this. I'm only running a new Denso in-tank pump and the last thing needed is for it to fail and to go lean at 25psi. I was previously looking into smaller catch can options, but all I came across where for motorcyle applications. Will these work on a car? Also, I've previously heard of the JDM cc option, but I haven't had luck sourcing one. Anyone know where I can find one? If not, anyone want to sell theirs?

Thanks for the info. I was not trying to mislead anyone or promote the removal of the catch can. I was merely trying to point people who are looking for a vented gas cap in the right direction as I've stumbled across several threads were members were asking. However, if they're harmful for our vehicles, I too would recommend against them.

 

[jdub]

Guys that sell 1JZ swaps...like DriftMotion

 

[IJ.]

JDM CC can still be bought new from Toyota, I'm sure there are many guys with front cuts that would sell you one.

[thumb]http://ij.supramania.com/meth06.jpg[/thumb]

 

[Doward]

Mostly on topic - anyone got a picture of the stock location of the JDM canister?

 

[dumbo]

Maybe a little more off topic but,

How does the stock system work, most importantly where is this 2psi had from?

I have no intention of removing mine my stock setup, but I think if you are to modify something you should first know how its supposed to work.

 

[Doward]

2 PSI of intake pressure is bled off to the CC where it is run back to the tank to hold a slight pressure and ease the pump's work.

 

[dumbo]

2 PSI of intake pressure is bled off to the CC where it is run back to the tank to hold a slight pressure and ease the pump's work.

What if its a NA?

 

[jdub]

John - Incorrect...the pressure comes from fuel evap. Look at this:
http://www.cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=EC&P=6

Intake vac is one way from the canister to the intake manifold. If vac occurs in the tank, there is a check valve in the stock cap that allows air in to prevent negative pressure.

 

[CassMori]

John - Incorrect...the pressure comes from fuel evap. Look at this:
http://www.cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=EC&P=6

Intake vac is one way from the canister to the intake manifold. If vac occurs in the tank, there is a check valve in the stock cap that allows air in to prevent negative pressure.

Which BVSV is that diagram showing? The one that mounts under the intake?

Anyone have a diagram, or link to one, showing how the JDM cannister connects (assuming it is different from the USDM)? On either version, does it connect with the EGR system? My car has not had either since I've had it; but, if it will help performance/reliability, I'd like to start looking into installing one. Especially since I have the entire top end of the engine apart at the moment.

edit: for JDM cannister, I mean the original vacuum system for JDM 7MGTE cars, if I was unclear.

 

[Doward]

John - Incorrect...the pressure comes from fuel evap. Look at this:
http://www.cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=EC&P=6

Intake vac is one way from the canister to the intake manifold. If vac occurs in the tank, there is a check valve in the stock cap that allows air in to prevent negative pressure.

I see what you're saying - I misspoke.

The BVSV is pressurized under boost, and the check valve keeps the system pressurized to 2psi when under boost, as well. When you get off the turbo, the vacuum signal is stopped at the check valve.

Do I have this correct?