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· Enter The Supra
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Discussion Starter · #1 ·
Do any of you guys know the best route between the fuel tank and body for a fuel vent line? I moved my charcoal can to the rear of the car, inside the rear bumper, and am running a new vent hose to this from the fuel pump housing. I'm not sure how to route the line though, as there seems to be no clearance for anything between the body and fuel tank. The hose keeps getting pinched down no matter which way I try to go. I'm sure someone knows where the bigger gaps are between the body and fuel tank to fit the 3/16" hose I'm using.
 

· Is it turbo? Is it stick?
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Interesting... I'd like to know the same. I deleted my charcoal canister so I just want to vent the tank to open air... I had it routed inside the passenger quarter panel but ran into the same issue as you where it got pinched and was causing the tank to build up pressure, so as a temporary fix I just popped the hose off and it is venting directly out of the vent port at the top of the tank. Its something I'd like to take care of sooner or later though. Maybe reuse an original small diameter hardline to route it from the top of the tank, then soft line once its got some more room?
 

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Very interested in that issue...
I have also deleted my carchoal canister,and sealed the rubber hose that
comes from the tank. Everytime I go to the gas station and open the fuel
cap a huge amount of 'psssssss' pressure comes out.
Is that bad? I know it builts pressure....but is this going to influence the
fuel system?
 

· Enter The Supra
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Discussion Starter · #7 ·
Get a vented gas cap and cap it off. That should work fine.
Well, the reason I'm putting the charcoal can back in the car is b/c my garage always smells of gasoline. I had the oem line vented to the atmosphere and I don't see why a vented cap wouldn't cause the same problem (I didn't explain this earlier, but that is the issue I have). I've read some threads on here that lead me to believe the charcoal can will fix this issue.
 

· Supra OG
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Bob is talking about doing the same setup I have shown below with the canister in the rear bumper. You can see a hard line has been added that goes across the top of the tank and toward the rear bumper. I didn't install this mod but it sounds like the reason for the hard line is to avoid pinching a rubber hose.



 

· Enter The Supra
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Discussion Starter · #9 ·
^^Exactly. Fitting the can in was actually the easy part. I haven't had much time to work on it today, but I need to figure where to route cause that's completely stopped the project. I really don't want to drop the tank, but my options are a bit limited. Does anyone know what kind of tubing can be used to make a line like Jim has on his car above? I was thinking brake line, it's strong and can be bent a bit, maybe there's something better?
 

· Factory RSP Hardtopper
2015 Ram 2500 Coal Roller
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I ran my vent on the triple Walbro setup from the vent to the back of the tank and used a coat hanger to fish it down. Now I just need to source a charcoal canister.
 

· Is it turbo? Is it stick?
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You can lower the tank just a bit if you just need some room, thats easy... just take the metal shield off and then either just loosen 2 of the tank strap bolts, or loosen all 4, or take 1 or 2 of them off. The tank wont drop all the way out, but it will lower some and give you a little room. You still won't be able to see much though.
 

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Discussion Starter · #12 ·
I did already loosen the 2 rear strap bolts to lower the tank just enough to run the line down, the problem is when you tighten the bolts back up, it pinches the line. Like I said, I don't know where the most clearance is between the fuel tank and the body to route the line so it will not get pinched. Toyo Terrorist, are you certain your line is not getting pinched down? Once I started tightening the strap bolts, I couldn't even wiggle the line anymore. I probably should just run some compressed air through it to see if it comes out the other side.
 

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you guys are aware that toyota designed the fuel system to be pressurized right? about 1psi-2psi above nominal (atmospheric).

Check the TSRM and fuel evap system.
 

· Is it turbo? Is it stick?
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When I ran a soft line to vent my tank, I dropped the tank and ran it in a very intentional route to avoid pinching, but it got pinched anyway. I knew it got pinched because I had fuel pushing up through the seal where I installed my second pump/line on the hanger, and fuel was puddling in that area on top of the tank. When I disconnected the pinched hose so that it was just an open nipple on the top of the tank, the pressure dropped and the leaking stopped.

I know I have a modified fuel system with the second pump and second line, but in my case however much pressure had built up was a bad thing for sure, and was causing a fuel leak.
 

· Supra OG
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^^Exactly. Fitting the can in was actually the easy part. I haven't had much time to work on it today, but I need to figure where to route cause that's completely stopped the project. I really don't want to drop the tank, but my options are a bit limited. Does anyone know what kind of tubing can be used to make a line like Jim has on his car above? I was thinking brake line, it's strong and can be bent a bit, maybe there's something better?
Bob,
My tank is actually dropped about an inch using spacers so I had no pinching issues. The reason for this was so that the fuel system fittings would clear the tank cover (rather than having to remove the cover or modify it to clear). The alternative way you may be able to route your line is to use the existing stock hard line from the tank that goes to the front to connect into the stock cannister location. You could cut that hard line where it exits from the tank area and run your rubber hose from there.

JimE
 

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Discussion Starter · #19 ·
Jim,
So your tank is lowered? That's the "magic bullet"? I've been racking my brain trying to figure out how to do this and it's that easy. hah, I think I am taking the route of cutting the hardened oem line and connecting the hose from there. I just need to get under the car and trace which line it is now. Just want to get this car back together! As always, thank you for the help.

-Bob

Bob,
My tank is actually dropped about an inch using spacers so I had no pinching issues. The reason for this was so that the fuel system fittings would clear the tank cover (rather than having to remove the cover or modify it to clear). The alternative way you may be able to route your line is to use the existing stock hard line from the tank that goes to the front to connect into the stock cannister location. You could cut that hard line where it exits from the tank area and run your rubber hose from there.

JimE
 

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Just use the stock lines and charcoal canister, there isn't any flow through it besides air basically, so you really dont need bigger lines. If you take out the charcoal can it will smell like gas everywhere if its vented to atmosphere, but if you clamp the line to the charcoal can and remove the charcoal can, the tank will pressurize a ton and thats bad/ youll get fuel leaks in badd places. you also shouldnt vent to atmosphere because like some dude up there ^ said, the toyota system is designed to have SOME pressure, but not a ton (clamped line+no charcoal can), but shouldnt have NO pressure (line vented to atmosphere)

Just use the stock setup for venting
 
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