View Full Version : Gas tank vent hose routing
Blue Viking
06-12-2022, 12:53 AM
I routed the hose from the gas tank vent according to FFR instructions, but I am a bit concerned about the routing of the hose. It doesn't go very high up, certainly not above the filler neck. Is there a check valve in the vent itself to prevent gas from spilling out? I am concerned that when I fill it up full, gas will be pouring out via the vent.
facultyofmusic
06-12-2022, 03:18 AM
I never thought about this in detail, but are we actually supposed to fill it all the way up the filler neck?
I installed mine like this and have had no issues with fuel coming out with a full tank. I also did the Breeze 1/2" big bore vent line, larger than the FFR supplied vent hose.
https://breezeautomotive.com/shop/big-bore-vent-check-valve-kit/
https://thefactoryfiveforum.com/attachment.php?attachmentid=134320&d=1598416998
https://thefactoryfiveforum.com/attachment.php?attachmentid=134319&d=1598416985
Blue Viking
06-12-2022, 10:48 AM
Well not really all the way up, but I usually let it run until it shuts of automatically, which leaves the gas quite high in the tube, above tank level at least.
edwardb
06-12-2022, 04:20 PM
The check valve in the top of the tank is just a simple ball in a cage. You can hear it rattle when you shake it. It's open when he tank is upright. Closes by gravity when the tank is inverted to limit fuel coming out. Not that you really want it to be in that position. :( It's far enough above the filler tube that I don't think fuel would reach that far even if you fill the tank so much it's coming out the filler. Typically the gas station filler switches off before coming up he tube just by the vapor alone. Let it stop there and you won't have any issues.
I too have used the larger valve from Breeze. Supposed to improve venting and allow the tank to be filled faster and easier. Can't hurt although I suspect the stock one is OK if you don't get crazy with the fill rate.
BEAR-AvHistory
06-12-2022, 04:54 PM
Mine looks like Fman's picture except for a home made charcoal canister.
Geoff H
06-12-2022, 06:06 PM
I was running the stock valve and had to be very careful with filling too quickly or it would burp up gas. It would take me forever to fill up. I changed to the Breeze product and I can fill at whatever speed with no issue. I do not run a charcoal canister yet - mostly lazy as with no gas smell at all so far it landed in the leave’er list.
Lidodrip
06-12-2022, 07:45 PM
I was running the stock valve and had to be very careful with filling too quickly or it would burp up gas. It would take me forever to fill up. I changed to the Breeze product and I can fill at whatever speed with no issue. I do not run a charcoal canister yet - mostly lazy as with no gas smell at all so far it landed in the leave’er list.
I recently asked Mark at Breeze about getting his larger valve and he told me that FFR had changed their valve and it seemed to be less of an issue now. He recommended I use the FFR valve and if I ran into issues, I could switch it out later. I am not on the road yet, so I have no actual experience to report yet.
egchewy79
06-12-2022, 09:12 PM
I recently asked Mark at Breeze about getting his larger valve and he told me that FFR had changed their valve and it seemed to be less of an issue now. He recommended I use the FFR valve and if I ran into issues, I could switch it out later. I am not on the road yet, so I have no actual experience to report yet.
Mark’s honesty is commendable. Have you seen another businessman tell you not to buy their product?! So many stand-up guys in this cottage industry.
If the "new" FFR valve is 1/2" then you will be good, if it is smaller I would recommend going with Breeze kit while it is easy to route. Would be a real bummer having fuel over flow all over the place while filling up... Just my .02...
Blue Viking
06-12-2022, 10:23 PM
Thank you for the answers. I'll not worry about it then, and leave as is. I'll be trailering the car to get it weighed today, should stop by and fill it up at the pumps then. Not much fun with the $10/ gal gas prize though.....
facultyofmusic
06-13-2022, 12:50 AM
Thank you for the answers. I'll not worry about it then, and leave as is. I'll be trailering the car to get it weighed today, should stop by and fill it up at the pumps then. Not much fun with the $10/ gal gas prize though.....
Holy smokes $10 a gallon!? I thought $7 a gallon here was bad...
Blue Viking
06-13-2022, 09:37 AM
Actually it ended up around $10,80 / gal for 98 octane unleaded. Got a weight of 1130 kg with a full tank,actually thought it would be heavier.
facultyofmusic
06-15-2022, 07:45 PM
The check valve in the top of the tank is just a simple ball in a cage. You can hear it rattle when you shake it. It's open when he tank is upright. Closes by gravity when the tank is inverted to limit fuel coming out. Not that you really want it to be in that position. :( It's far enough above the filler tube that I don't think fuel would reach that far even if you fill the tank so much it's coming out the filler. Typically the gas station filler switches off before coming up he tube just by the vapor alone. Let it stop there and you won't have any issues.
I too have used the larger valve from Breeze. Supposed to improve venting and allow the tank to be filled faster and easier. Can't hurt although I suspect the stock one is OK if you don't get crazy with the fill rate.
Been thinking about this one. I looked at pictures of the rear of the car, location of the filler neck, and I can't see how it won't go into the vent tube if we fill it all the way up. The gas cap is so far above the top of the gas tank.
168151
Perhaps I just don't have a good picture of where the automatic gas filler stops?
edwardb
06-15-2022, 08:36 PM
Been thinking about this one. I looked at pictures of the rear of the car, location of the filler neck, and I can't see how it won't go into the vent tube if we fill it all the way up. The gas cap is so far above the top of the gas tank.
168151
Perhaps I just don't have a good picture of where the automatic gas filler stops?
If you look at where the filler goes into the side of the tank, it's going to stop there and go up the filler tube if you keep adding fuel. But it's not going to go above the filler on the side with only gravity pressure. This picture shows the space above the filler and the vent visible at the top. Even filled to the max, there's going to be a bit of airspace at the top. Keep in mind these tanks and a similar filler tube have been used on millions of Mustangs. Pretty well proven.
https://hosting.photobucket.com/images/ab234/edwardb123/IMG_3424.JPG?width=960&height=720&fit=bounds (https://photobucket.com/u/edwardb123/a/bb9829e6-c7f8-430e-ac38-96acbdd162f0/p/f9b1ec28-19eb-49d7-9991-59c9ff5665b0)
rich grsc
06-16-2022, 07:30 AM
As posted, it's a proven design used on millions of cars. Stop trying to invent a square wheel.:rolleyes:
Blue Viking
06-16-2022, 08:03 AM
As posted, it's a proven design used on millions of cars. Stop trying to invent a square wheel.:rolleyes:
Eh, that's kinda harsh... Besides, the design hasn't been used in a million cobras, so the question is valid. As it turns out, routing the hose the way FFR says, causes a drip out the vent hose when filling up full, so I'll reroute it a bit higher to stop that from happening.
toadster
06-16-2022, 12:54 PM
kindof interesting how everyone sets up different the FFR manual is horrible in this aspect for IRS and fuel tank venting... literally just attach a hose and mount it somewhere away...
the charcoal cannister setup is the way to go IMHO for best chance to not have a smelly garage :)
168162 168163
I'm sure someone has done it, but why not a single activated charcoal cannister for both IRS and fuel tank? I think the OEM mustang cannisters do this...
Eh, that's kinda harsh... Besides, the design hasn't been used in a million cobras, so the question is valid. As it turns out, routing the hose the way FFR says, causes a drip out the vent hose when filling up full, so I'll reroute it a bit higher to stop that from happening.
oh and don't worry, that's just rich ;)
Blue Viking
06-16-2022, 02:07 PM
[QUOTE=toadster;494815]kindof interesting how everyone sets up different the FFR manual is horrible in this aspect for IRS and fuel tank venting... literally just attach a hose and mount it somewhere away...
the charcoal cannister setup is the way to go IMHO for best chance to not have a smelly garage :)
168162 168163
I'm sure someone has done it, but why not a single activated charcoal cannister for both IRS and fuel tank? I think the OEM mustang cannisters do this...
oh and don't worry, that's just rich ;)[/
Not worried at all�� Found my answer, I'm happy.
Hoooper
06-16-2022, 02:54 PM
I'm sure someone has done it, but why not a single activated charcoal cannister for both IRS and fuel tank? I think the OEM mustang cannisters do this...
Why even bother venting the axle to a canister? The axle vent isnt going to stink up the garage at all. Ive never heard of running an axle vent to charcoal canister nor does it sound like a good idea to possibly get gas vapors into your axle.