Diesel Transfer Tank -Barometric Pressure Valve?

[Trimley]

As many of you are aware, I built this Diesel Transfer Tank.

Someone (here or elsewhere) suggested a one-way Barometric Valve, but I cannot seem to track down that info... I thought I'd bookmarked.

Does anyone have a suggestion for a 3/8" NPT (one-way?) valve?

Help is appreciated!!

 

[imnukensc]

Delete.

 

[North Idaho Wolfman]

I'll have to dig into my past purchases to see where I got mine.

 

[BAP]

Search “Fuel Transfer Tank Vent” on Amazon and there is all kinds of them in different styles.

 

[Trimley]

I'll have to dig into my past purchases to see where I got mine.

That would help me out a lot.

I've searched Amazon, Google and eBay with about every search term I can think of. I'm not finding a barometric pressure relief.

 

[Runs With Scissors]

That would help me out a lot.

I've searched Amazon, Google and eBay with about every search term I can think of. I'm not finding a barometric pressure relief.

Would something like this fuel tank vent work?

https://www.grainger.com/product/1U...VzDbUAR3lKA5yEAQYAiABEgLxYPD_BwE&gclsrc=aw.ds

 

[Trimley]

Would something like this fuel tank vent work?

https://www.grainger.com/product/1U...VzDbUAR3lKA5yEAQYAiABEgLxYPD_BwE&gclsrc=aw.ds

As a 2-way vent, yes. The problem is, it would breathe in both directions and pull moisture in.

What I'm wanting is a breather that opens only by internal built-up pressure. Atleast that's my understanding.

 

[Runs With Scissors]

As a 2-way vent, yes. The problem is, it would breathe in both directions and pull moisture in.

What I'm wanting is a breather that opens only by internal built-up pressure. Atleast that's my understanding.

I don't understand.

Then why have a vent?

I guess I am having a hard time picturing a "one way vent".

If the fuel gets hot and expands, and the vent is only one way, wouldn't that create 'vacuum" situation when it cooled off?

 

[Torinodan]

I don't understand.

Then why have a vent?

I guess I am having a hard time picturing a "one way vent".

If the fuel gets hot and expands, and the vent is only one way, wouldn't that create 'vacuum" situation when it cooled off?

Wouldn't also make it hard to pump fuel as it would only have a one way valve. Collapsing the tank?

 

[old and tired]

Thinking outside of the box, wouldn't an expansion tank (like for hot water heaters) be what you want? Rubber bladder that expands and contracts but doesn't let outside air in...

{EDIT} Oops, forgot about dispensing fuel!!!

 

[Smokeydog]

https://a.co/d/e5aLn2x

They do make brass 3/4” to 2” bell reducers for fuel tanks.

 

[Trimley]

I don't understand.

Then why have a vent?

I guess I am having a hard time picturing a "one way vent".

If the fuel gets hot and expands, and the vent is only one way, wouldn't that create 'vacuum" situation when it cooled off?

I agree. I'm kind of baffled at the necessity. A 1-way? (Shrug)

I already have/had a breather, so why the need?

I'm new to diesel, and to building a tank!

 

[Trimley]

Wouldn't also make it hard to pump fuel as it would only have a one way valve. Collapsing the tank?

That's my assumption as well.

 

[Smokeydog]

It’s a vacuum pressure vent. 1psi vac, 2psi pressure. Keeps vapor pressure above the fuel in to keep the humidity or water out. Reduces loss of evaporation of fuel. Us who live in high humidity need to store fuel this way.

 

[The Evil Twin]

Most ATVs have spring checks on the fuel cell. My Can Am does. Allows venting if the pressure goes too high. Allows air in if there is too much vacuum. Is that essentially what you are looking to achieve?

 

[North Idaho Wolfman]

My fuel tank has a positive vented cap for over pressure, and a negative pressure vent used when fueling from the tank.

https://www.supplyhouse.com/Cash-Acme-22397LF-1-2-NPT-VR-801-Vacuum-Relief-Valve-w-Dust-Cover-Lead-Free?utm_source=google_ad&utm_medium=pmax&utm_campaign=geo_pmax_test&gad_source=4&gclid=Cj0KCQjwxsm3BhDrARIsAMtVz6NKKfinx22XgqS1_mHPXm_3cPqju5mKVyMb5RQAsHJI_UugMQpAYIEaAuI5EALw_wcB

 

[Trimley]

It’s a vacuum pressure vent. 1psi vac, 2psi pressure. Keeps vapor pressure above the fuel in to keep the humidity or water out. Reduces loss of evaporation of fuel. Us who live in high humidity need to store fuel this way.

I think what you're describing, is what I'm needing. Are they available in 3/8"? A link is appreciated.

 

[Runs With Scissors]

I agree. I'm kind of baffled at the necessity. A 1-way? (Shrug)

I already have/had a breather, so why the need?

I'm new to diesel, and to building a tank!

I am not a "tank builder", but I did retrofit a tank from a boat and adapted it to fit in my truck bed.

I used a simple "elbow" to vent it.

I have never had a "water problem" in the 5'ish or so years I've had it.

But then again, I have never had any of the problems with diesel that I hear so much about.

Maybe I'm just lucky.

It holds ~70 gallons plus the original tanks ~38 gallons.

It's nice not to have to stop for fuel for about 1600 miles. (although my bladder can't do that)

Although filling it takes a little longer, and paying a $400-$500'ish bill sucks.

My "Google Fu" must be weak, cause I can't find anything like what your asking for, but please post a link when you find it cause it's driving me mad.

 

[Sidekick]

Years ago I designed some medical equipment for cooling a body after heart surgery that needed expansion breathing on the liquid tanks hooked to the catheter. I used vents that have a membrane that allows air to pass but blocks compatible liquids. They were called hydrophobic vents. You would have to verify diesel compatibility. They did not let moisture or liquid to pass. Many outdoors sealed nema enclosures use them for venting.

 

[Trimley]

Search “Fuel Transfer Tank Vent” on Amazon and there is all kinds of them in different styles.

I did, originally. Unless I missed it, all I found were different types of 2-way breathers?