I’m looking for ideas on what to do with my tank vent. I’ve read just about everything I could find online on the subject here on the HAMB and elsewhere. I’ve fitted my tank with a rollover vent from Tanks , but I’m at a loss for what to do with it from there. I obviously can’t go upwards because there’s only about 2” of bed above the top of the tank. What I’m wondering is what to do with the vent hose off the rollover valve barb and also wondering if I’m going to experience any gas smell from the vent Anyone with a T with an exposed tank ? If so what did you do? Anyone else have any ideas ? I don’t see a lot of options with this thing.
You only have 3 options as I see it. A) The only higher place is the cab and I don't think you want to run a vent line up the back of your cab. B) Pipe the overflow down somewhere, maybe through the floor. C) Plug that hole and vent your cap or install a breather in the overflow port. Be really careful when you fill up. I think this is your best option.
I've always used a vented cap on several cars with a similar tank in bed/or exposed on back tanks with no problem. In this case it should work to run a hose off the vent and thru the floor and or lose the valve and run a metal line instead. To avoid gas smell or possible heat expansion overflow in the garage, I usually leave the fuel level low when returning and fill up when leaving. Anyway to find a shorter more automotive looking fitting on the fuel pick-up?
You know I’m starting to think that the thru the bottom of the bed option might be possible. I was concerned that I might get fuel leakage or maybe even fuel siphoning out the vent however I don’t think that would happen based on the design of the rollover vent. It is a 2 function vent in that when the fuel level is high there is a phenolic plastic check valve that floats (is pushed up) to close the valve. Below that is the steel ball that will shut the valve positively in the event of rollover. In theory the valve should shut off the fuel to the vent when it’s high enough to cause siphoning and allow the tank to take in air as the fuel level drops. So, unless I’m wrong I should be able to route the vent down below the top of the tank and not have a problem. This picture shows a cutaway of the valve. The fuel pickup fitting is a 1/4” NPT street elbow, NPT to 3/8” inverted flare is automotive and about as short as they come. I will have a look for a different style fitting, I’m not sure what’s available.
That valve should work fine, in this thread there is some good ideas about a small charcoal can on the end of the vent hose. They stay open to let air back into the tank taking the fuel vapor back also. No smell. https://www.ffcars.com/forums/17-fa...-charcoal-canister.html#/topics/198409?page=1 Sent from my SM-G900V using The H.A.M.B. mobile app
I have a rollover valve/vent from Rock Valley in my car, and I just ran a line over to the side of the tank and down. It ends at the bottom of the frame rail. I've never seen any evidence of it leaking out fuel, or smelled any strong gas fumes from there. The car has plenty of other smells (including gas smells near the engine), but nothing strong from that vent/valve.
I have a plan. In formulating it I called my local buddy who also has a 27 RPU and asked him what he had done with his fuel vent. His cars been on the road for a long time now and he just came off the vent valve and over a little bit and then down through the bottom of the bed. Simple and easy and no problems
Something like an Edelmann 122640 or Weatherhead 402X6 are 1/4" NPT by 3/8" inverted flare 90 street els and are more automotive looking than the cast "house" looking version you have. Nothing wrong with it, sure it will be totally functional; but just one of those things that get noticed.
I know what you mean, when that fitting was handed to me at the parts store I had my own reservations about the way it’s made and looks. It’s sort of elegant looking rather than more robust or utilitarian in appearance. I’m changing it out, my parts guy will have one of these for me tomorrow. Fairview 149-6B 3/8 TUBE X 1/4 MALE PIPE
My t-bucket has a tiny hole (1/16) in the cap, sometimes I wonder if it's even big enough to allow enough gas flow up to my carbs. My truck has the vent ran through the floor like you are talking about doing and honestly going under the back of the truck on a creeper I do smell it.
Run your vent hose below the bed and put one of these on it to keep the dirt out. https://www.amazon.com/Parker-EM25-Sintered-Bronze-Muffler/dp/B003Q6CBNY
So, I decided that I didn’t want to use the hose barb on my rollover vent. I picked up a brass 1/8 NPT coupler and took the valve apart for silver brazing. Now I can plumb the vent with hard line.
And now the vent is finished and the tank is bolted in for the final time. Ready for fuel when the time comes. As you can see I made the vent line go up as much as I could and then down thru the bed. And that wraps up this thread
In addition to my other projects, im also working on an OT Harley and WAS having a difficult time figgering out a work around with a fuel line fitting issue. Thank you, for this thread... it should solve the problem. I will try this and see how it goes. ...and i was just reading this thread for my 28 Chevy build... who knew... lol Sent from my SM-N920P using The H.A.M.B. mobile app
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