difference in water and fuel cans

#1
ok since fuel cans are so rediculious in price ive been lookin at water cans. now i know it should never be done(puting fuel in a container marked water)but i am the ONLY one that will be using these and then if someone steals em and drinks the WATER ill be even happier jk. but ive heard of people using the plastic water cans for fuel and being just fine, but wanted your guys opinion. dont tell me not to do it cause its a water jug. tell me why other than what i already stated.
 
#2
If I'm not mistaken, the formulation of the plastic is different between Scepter fuel cans and Scepter water cans. The fuel cans are more resistant to the chemicals of the fuel, I've heard.

BTW, I'd hate to be around when somebody grabs your "water" can to put out a fire in an emergency!
 
#4
As Crusader said the plastics are usually different. Won't happen the first time you use them (then again depending on the quality it might) and maybe not the 5th or 10th but water containers will eventually leak if used to carry fuel.
 
#5
OH...It wasn't stated, but presumably we're talking about Scepter cans here, (since wal-mart gas cans and metal jerry cans are cheap and plentiful) so an additional difference between the Scepter MFC and Scepter water can is that the water can has no rubber sealing gasket like the MFC. The seal is a plastic friction-fit seal that relies on...well, I suppose it's the surface tension of the water, to keep the water from seeping past the sealing surfaces.

Also, and I'm too lazy to go out and confirm this, I think the threading for the cover on the MFC is different than on the water container. The cover is certainly different, but I think the threads may be also, so one might find it difficult to get the fuel from the water jug into a gas tank without a proper fuel spout to attach to the water can. Again, I haven't strolled out to the garage to confirm this bit.
 
Last edited:
#6
OH...It wasn't stated, but presumably we're talking about Scepter cans here, (since wal-mart gas cans and metal jerry cans are cheap and plentiful) so an additional difference between the Scepter MFC and Scepter water can is that the water can has no rubber sealing gasket like the MFC. The seal is a plastic friction-fit seal that relies on...well, I suppose it's the surface tension of the water, to keep the water from seeping past the sealing surfaces.

Also, and I'm too lazy to go out and confirm this, I think the threading for the cover on the MFC is different than on the water container. The cover is certainly different, but I think the threads may be also, so one might find it difficult to get the fuel from the water jug into a gas tank without a proper fuel spout to attach to the water can. Again, I haven't strolled out to the garage to confirm this bit.
x2

MWC' would leak fuel like crazy on a rough road IMO. No bueno.
 

Martyn

Supporting Sponsor, Overland Certified OC0018
#7
Water cans are typically lined with a food grade plastic. Don't know how that will react with fuel.
 

cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
#8
A note from an older thread on using the Scepter specific MWC's for fuel...

Its not just the gasket being absent, the water cans only have a ~1/8" lip on the top of the cans, where as the fuel cans have a 1/2" flat lip and still can drizzle a bit of fuel. Not to mention the lack of venting system (which is pretty neat on the MFC's and the thinner plastic, albeit the same plastic (as I was reported in a different thread). Having looked at the cans pretty closely side by side, I just don't see it being feasable or safe.
 

CJCA

Adventurer
#9
ok since fuel cans are so rediculious in price ive been lookin at water cans. now i know it should never be done(puting fuel in a container marked water)but i am the ONLY one that will be using these and then if someone steals em and drinks the WATER ill be even happier jk. but ive heard of people using the plastic water cans for fuel and being just fine, but wanted your guys opinion. dont tell me not to do it cause its a water jug. tell me why other than what i already stated.
This is the reason why I would never buy used drinking water containers. You just never know what has been put in them. I'm sure that in an emergency more than a few MWCs have been used for fuel, used as a urinal, for hazardous waste, etc. None of which I want in contact with my drinking water.
 
#10
I explored this pretty indepthly a year or two ago. MY goal was to use the buylci.com water cans for fuel. They are very very close to the Scepter water cans. I ended up deciding not to do it. I researched out the military spec for the scepter fuel cans and recreated the testing on the LCI cans. Not using the same MFC spout... wasn't a big deal as i was going to use a super siphon. Putting viton orings on the vent and hose bib was simple and sucessful.

The problem came on the main lid seal. As Kurt said, the water can only has a 1/8" lip instead or the 5/8" flat ribbed seal surface. The water can uses a traditional "wedge" to seal within the cap. You see this being used on regular old gas cans from home depot. One of the reasons you don't want to use regular old cans is because this seal does not work when bouncing around and when the can changes temp. I attempted to install a large viton oring into this sealing area with very little success. I'd have to look up the military spec, but the can had to hold liquid under a certian pressure for a certian amount of time. I could not get it to meet either requirement. I could take it to about half the pressure required but could never get it to hold it for the time needed.

I was not too worried about the material or the plastic thickness. The LCI cans are made out of a single material, High Density Poly Ethylene(HDPE). From my discussions with LCI and tearing apart a can, there was no lining. The water cans are also a little thinner walled than the fuel cans. This also was not too much of a concern for me as the regular cans from Home depot are much thinner than the water cans. When doing the pressure test (I did it succcessfully on a Scepter MFC) the LCI can did swell more than the MFC, but not by much. I was only looking to use them for fuel storage in my garage so the heat and bouncing wasn't a big deal. I still opted to not use them at this point. Could you use them for emergencies, yes. They might be better than a regular plastic gas can, but probably not worth the risk.
 

IggyB

Adventurer
#11
When I bough the Scepter cans a few years ago ( directly from Scepter :) ) I was told by them that materials for gas and water cans are same.

The problem I see is the amount of vapour that gasoline will generate compared to water. Scepter gas cans are rated to 30 psi. Water cans will not seal nearly as well. Even with the gas cans I wind up using a strap wrench to tightly seal gas cans after torquing them as much as possible with bare hands.
 
#12
cruisertoy thanks for the reply i was also looking at those water can and was going to use em inmy garage, thanks for doing all the foot work and going through the trouble to tell me what the difference was and not just a dont do it answer. with those facts i agree its not worth the risk of leaking fuel and having vapors around the shop. thanks again.
 
#13
cruisertoy thanks for the reply i was also looking at those water can and was going to use em inmy garage, thanks for doing all the foot work and going through the trouble to tell me what the difference was and not just a dont do it answer. with those facts i agree its not worth the risk of leaking fuel and having vapors around the shop. thanks again.
No problem. I do this type of product testing for a living. I really wish it had worked out to use them. I really like the scepters, but the Nato metal cans are pretty good as well. There are a few places around that still sell them. Good luck.
 
#14
Another variable

How about the use of pre-ban Wedco water cans for fuel? Using the super siphon method, so spouts wouldn't be an issue. I'm in the process of trying to acquire some pre-ban/old style Wedco/NATO fuel cans and it's impossible, and I'm not going with the post ban plastic lid child proof versions. Thought I'd throw it out there since these types of water cans are not plastic. I realize that they have a sanitary coating inside, but besides that I don't see any other reason, except the fire one previously mentioned. Thanks.
 
Top