Jerry Can Advice (1 Viewer)

[DPA200]

I’m putting a rear bumper on my 200 next week. It’s a dual swing out, and has a holder for 3 Jerry cans. I ordered 2 20L beige water cans from WitsEnd, but I also want 1 20L fuel for the 3rd spot. I have a 2 gallon rotopax that fits (if I bought a 2nd one it’d fill that spot), but in the past year I used the rotopax I’ve grown to despise how it doesn’t self vent. Extreme Altitude and temp changes are a common occurrence and it’s a pain to have to open to vent sometimes multiple times in a day. Any advice on where and what to buy for a high quality 20L fuel can

 

[Markuson]

I’m putting a rear bumper on my 200 next week. It’s a dual swing out, and has a holder for 3 Jerry cans. I ordered 2 20L beige water cans from WitsEnd, but I also want 1 20L fuel for the 3rd spot. I have a 2 gallon rotopax that fits (if I bought a 2nd one it’d fill that spot), but in the past year I used the rotopax I’ve grown to despise how it doesn’t self vent. Extreme Altitude and temp changes are a common occurrence and it’s a pain to have to open to vent sometimes multiple times in a day. Any advice on where and what to buy for a high quality 20L fuel can

View attachment 2006301

In my use of Rotopax including from sea level to over 13,000ft and even the reverse without venting... -Rotopax don’t need to vent because they can handle swelling without structural stress. My three 4 gallon Rotopax swelled significantly, and have NEVER leaked unless I goof on putting the seal ring in or something. Occasionally I have to put cans temporarily inside the vehicle, and the last thing I want is fume venting.

 

[DPA200]

In my use of Rotopax including from sea level to over 13,000ft and even the reverse without venting... -Rotopax don’t need to vent because they can handle swelling without structural stress. My three 4 gallon Rotopax swelled significantly, and have NEVER leaked unless I goof on putting the seal ring in or something. Occasionally I have to put cans temporarily inside the vehicle, and the last thing I want is fume venting.

Interesting, I’d thought I’d ready somewhere that you had to vent in extreme altitude or temp changes. Last summer I went all over Utah, Wyoming and Montana, and it was nothing but extreme changes. So I kept stressing over it, as I could see the can bulge up, and I’d vent. The part that drove me nuts was that when the can did swell it was nearly impossible to open the spout . So basically you saying just ignore the bulge and if it doesn’t leak I’m all good? Would be the easier option to just buy a 2nd rotopax to fill the spot. I do see they have some tool to help open the lid

ROTOPAX Tool

Tired of struggling to open your RotoPax containers? This handy tool gives you the extra grip you need! Available in black Is used for loosening the Rotopax mount handles and also the fuel container caps. Does not fit water container caps. Made from high density ABS and precision cut for a tight...

www.isotallc.com

 

[Markuson]

Interesting, I’d thought I’d ready somewhere that you had to vent in extreme altitude or temp changes. Last summer I went all over Utah, Wyoming and Montana, and it was nothing but extreme changes. So I kept stressing over it, as I could see the can bulge up, and I’d vent. The part that drove me nuts was that when the can did swell it was nearly impossible to open the spout . So basically you saying just ignore the bulge and if it doesn’t leak I’m all good? Would be the easier option to just buy a 2nd rotopax to fill the spot. I do see they have some tool to help open the lid

ROTOPAX Tool

Tired of struggling to open your RotoPax containers? This handy tool gives you the extra grip you need! Available in black Is used for loosening the Rotopax mount handles and also the fuel container caps. Does not fit water container caps. Made from high density ABS and precision cut for a tight...

www.isotallc.com

I don’t doubt that it’s recommended you do vent. If filled at sea level, and driven to high altitude (as I have done), you certainly want to open them making sure the air pocket is under the cap so the expanded air doesn’t propel fuel at you...but with even a wee bit of care, it’s fine.

I have discovered that if you don’t mind them ballooning a bit (and staying slightly more that way) the Rotopax is unbelievably robust and has never leaked.

That’s why—if I knew I had to put fuel inside longer term, I would want it to be Rotopax.

 

[kevinfoutch]

My experience with roto’s and heat/altitude resulted in swelling, but no biggie from a containment perspective. However if you want to get those extreme swollen rotos off of a fixed roof mount, for example, you’ll need a pry bar to loosen the mount handles

In my 2x2 setup, I had one mount ‘pop’ open but thankfully the second mount stayed secure to keep from flying off the roof - just couldn’t remove them even with only one handle mount.

And to get the cap off if you actually want to use the gas inside, you’ll need the strongest grip you can muster to twist off the caps. Even venting was horrible.

The containers themselves handle the swelling , sure, but to use them if mounted was my biggest issue.

Switched to Jerry cans with hopes that swelling won’t affect usability but time will tell this summer. Jerry’s have to be more functional, can’t imagine it being worse. Yrmv

 

[DPA200]

My experience with roto’s and heat/altitude resulted in swelling, but no biggie from a containment perspective. However if you want to get those extreme swollen rotos off of a fixed roof mount, for example, you’ll need a pry bar to loosen the mount handles

In my 2x2 setup, I had one mount ‘pop’ open but thankfully the second mount stayed secure to keep from flying off the roof - just couldn’t remove them even with only one handle mount.

And to get the cap off if you actually want to use the gas inside, you’ll need the strongest grip you can muster to twist off the caps. Even venting was horrible.

The containers themselves handle the swelling , sure, but to use them if mounted was my biggest issue.

Switched to Jerry cans with hopes that swelling won’t affect usability but time will tell this summer. Jerry’s have to be more functional, can’t imagine it being worse. Yrmv

Yeah you are reminding me of my struggles last summer. I had the rotopax mountd on my Gobi ladder. I was paranoid about the venting, being the altitude and temp changes were causing serious swelling. So the caps were near impossible to twist off, but now i remember the swelling so much i couldnt get the can off the mount. Well, I never had a leak with all that, just felt like a pain. Might be better now with my new bumper, that I'm just placing in a jerry basket with a strap (no mount).

 

[TonyP]

I have some extra military style scepter tanks.
Heavy duty. They aren't cheap though.

 

[DPA200]

I have some extra military style scepter tanks.
Heavy duty. They aren't cheap though.

it's not like Rotopax are cheap either, my $79 only gets me 2 gallons. You know any place to get the heavy duty cans like yours?

 

[TonyP]

it's not like Rotopax are cheap either, my $79 only gets me 2 gallons. You know any place to get the heavy duty cans like yours?

My storage unit
I'll sell a couple if you want one. I'm out of town though so you'll have to wait a bit.

 

[linuxgod]

In my use of Rotopax including from sea level to over 13,000ft and even the reverse without venting... -Rotopax don’t need to vent because they can handle swelling without structural stress. My three 4 gallon Rotopax swelled significantly, and have NEVER leaked unless I goof on putting the seal ring in or something. Occasionally I have to put cans temporarily inside the vehicle, and the last thing I want is fume venting.

You're crazy @Markuson! Maybe you *can* avoid venting it, but I wouldn't. If you don't I would not be shocked if it eventually blows the seal on the cap or bursts a seam. I also frankly wouldn't be shocked if it caught fire if it blew a seal.

I have a 4 gallon rotopax I strap to my roof just when I go out west. I've done some mountain passes where I stop to vent it afterwards and it's near impossible to get the straps off because of how much it swelled. Once when I opened it the fuel was literally boiling from the pressure inside and actually sprayed out when I opened the cap too quickly.

If I had a rear bumper I'd absolutely strap regular self-venting jerry cans to it instead of a rotopax (for fuel, anyway).

 

[Markuson]

You're crazy @Markuson! Maybe you *can* avoid venting it, but I wouldn't. If you don't I would not be shocked if it eventually blows the seal on the cap or bursts a seam. I also frankly wouldn't be shocked if it caught fire if it blew a seal.

I have a 4 gallon rotopax I strap to my roof just when I go out west. I've done some mountain passes where I stop to vent it afterwards and it's near impossible to get the straps off because of how much it swelled. Once when I opened it the fuel was literally boiling from the pressure inside and actually sprayed out when I opened the cap too quickly.

If I had a rear bumper I'd absolutely strap regular self-venting jerry cans to it instead of a rotopax (for fuel, anyway).

Like I say... I’m sure venting is recommended. Really just saying they are extremely robust, and are made to be mounted upright, or sideways. I would occasionally vent, but my comment about elevation was more about their amazing sealing and robustness. Not meant as a recommendation.

Curious though. Rotopax basically don’t have “seams.” How do you feel it would catch fire on swingouts? Not trying to dispute...just trying to follow your thought on it catching fire. They deform rather than crack. If they self-vented, no one would be able to mount them on their sides as they are designed to do. Curious what you think.

I no longer mount Rotos (subtank) but when I did, expansion wasn’t extreme because there wasn’t much air in them in my use. If they were empty, then I left them to vent upright in back since huge amounts of air would expand way more... but zero issues ever.

 

[RET2]

Am I being overly simple by suggesting not cranking the Rotopax down as far there by allowing some venting if pressure builds to high? The old KISS solution.

 

[linuxgod]

Mine gets mounted horizontally on my roof, so maybe it's different because the minimal amount of air spreads out?

My big fear is that the pressure would cause the O-ring to blow out and then boiling fuel would be spraying everywhere (exhaust pipe included). I suppose with sufficient pressure the fuel could ignite in the canister as well (since there's no expansion tank), but gas boils at 200F and doesn't ignite until about 500F so that seems unlikely.

 

[linuxgod]

Am I being overly simple by suggesting not cranking the Rotopax down as far there by allowing some venting if pressure builds to high? The old KISS solution.

Maybe if it's mounted vertical. On my roof not fully tightening the cap would just result in gasoline pouring down my roof

 

[Markuson]

Maybe if it's mounted vertical. On my roof not fully tightening the cap would just result in gasoline pouring down my roof

That’s what I was envisioning (a vent meaning they’d leak all over). Seems they’d have to be able to candle it, or you’d have to dismount flat mounted ones any time you drive to high altitude before you could manually vent them upright.

I filled them very full since air expands a ton and fuel not... if they hyper-expanded, it was more when empty bc of air expansion.

One thing that’s obvious when you pick up an empty or look inside...RP are REALLY thick-walled, and the cap is super robust with a deeply-buried seal. I dunno... Just thinkin...

 

[RET2]

Mine mounts vertically, I didn't consider horizontal placement. It would be hard to imagine the gas getting anywhere close to 200 degrees inside the Rotopax, and not filling them to the brim would give some mitigation.

 

[Markuson]

Mine mounts vertically, I didn't consider horizontal placement. It would be hard to imagine the gas getting anywhere close to 200 degrees inside the Rotopax, and not filling them to the brim would give some mitigation.

View attachment 2006783

On the other hand...filling them FULL means expansion would be tiny since air expands a ton and liquid not.

This one better not be self-venting!

 

[RET2]

But we're talking venting here so are you advocating venting liquid gasoline? Air compresses, liquid not so much. Remember what our fathers told us about not buying gas in the heat of the day? Even today's gas pumps state gas is 231 cubic inches?

 

[Markuson]

But we're talking venting here so are you advocating venting liquid gasoline? Air compresses, liquid not so much. Remember what our fathers told us about not buying gas in the heat of the day? Even today's gas pumps state gas is 231 cubic inches?

Hey Ralph... Not sure who you are responding to.
(Hit that REPLY button under the post you are responding to, & it will automatically quote them).

 

[DPA200]

I have some extra military style scepter tanks.
Heavy duty. They aren't cheap though.

on the scepter cans is there any difference between diesel and petrol?