Scepter "Military" Fuel Can Gasket Alert!

teotwaki

Excelsior!
This information is very important to safe fuel storage in Scepter MFCs as well as the proper use of the two types of Scepter gaskets: Standard Rubber and Viton

Standard Rubber gaskets are only to be used with diesel fuel. Viton is meant for gasoline but could be used for diesel storage but was not reccommended.

These facts are straight from Scepter and are not on the web site. I had a good conversation with their tech guy and tried hard to take good notes to share here on the Portal. This information applies to both commercial and military issue versions of their fuel cans.

160_group_gas.jpg


In a nutshell: do not use the Standard Rubber gaskets for gasoline storage as lid damage will occur. The lid's inner plastic lip that holds the gasket in place will be sheared off by swelling of the rubber. The gasket will seal improperly and will fall out of the lid. I have a used can that this happened to when the previous owner stored gas in the cans. I replaced the entire lid and gasket with a red strapped lid and a gray Viton gasket.

How do I tell which gaskets I have?

It will depend on the age and source of the cans, especially if they were actual US military issue.

Recent commercial issue cans can be easier to deal with if they are color coded for fuel type. Either the entire can or at least the retention strap on the cap will have a color related to fuel type.

For the last two years Viton gaskets have been a gray color and standard rubber have been black colored. There are no part numbers or markings on theses two types. If you bought old stock this color scheme might not be true even for color coded cans.

Gaskets on old stock can be black for both Viton and standard rubber, even if the can or strap are color coded. If you have a black gasket on a can that you think is for gasoline you have to remove the gasket and inspect the gasket's edge. Black-colored Viton gaskets will have a small notch that is colored yellow.

Military Issue Cans

Now it gets complicated. The bulk of US Government purchased cans do not have color coded straps, are a "mud" color ("field drab" not OD Green) and have rubber gaskets. They were meant for diesel fuel only.
160_04820.jpg


The bulk of the US Government orders only had black gaskets, whether Viton or Standard Rubber. Individual gaskets were not normally replaced. Instead the entire lid with the proper gasket would be installed.

I have four used cans that are military surplus, two of them are field drab and one of those had a damaged gasket retention lip inside the lid. The other two cans are OD green and had diesel fuel in them but I need to carefully inspect the gaskets. I'll post up any pictures that may be useful. None of these cans had color coded straps.
 

ntsqd

Heretic Car Camper
With the original for a pattern one could make a new gasket if the correct one isn't easily available. McMaster will have most of the desired polymers in sheet stock.

I've a Parker O-Ring Design Manual that lists chemical compatibility with the commonly used O-Ring polymers and these are it's listings:

Ideal polymers for a Gasoline gasket:
Nitrile NBR
Hydrogenated Nitrile HNBR
Fluorocarbon FKM
Hifluor FKM "Viton"
Perfluorolastomer FFKM
Fluorosilicone FVMQ

Ideal polymers for a Diesel gasket:
Nitrile NBR
Hydrogenated Nitrile HNBR
Fluorocarbon FKM
Hifluor FKM "Viton"
Perfluorolastomer FFKM
Polyacrylate ACM
Fluorosilicone FVMQ

Note that the only difference is the Polyacrylate listing for gasoline. I'd like to know what polymer their "standard rubber" is.
 

teotwaki

Excelsior!
With the original for a pattern one could make a new gasket if the correct one isn't easily available. McMaster will have most of the desired polymers in sheet stock.

I've a Parker O-Ring Design Manual that lists chemical compatibility with the commonly used O-Ring polymers and these are it's listings:

Ideal polymers for a Gasoline gasket:
Nitrile NBR
Hydrogenated Nitrile HNBR
Fluorocarbon FKM
Hifluor FKM "Viton"
Perfluorolastomer FFKM
Fluorosilicone FVMQ

Ideal polymers for a Diesel gasket:
Nitrile NBR
Hydrogenated Nitrile HNBR
Fluorocarbon FKM
Hifluor FKM "Viton"
Perfluorolastomer FFKM
Polyacrylate ACM
Fluorosilicone FVMQ

Note that the only difference is the Polyacrylate listing for gasoline. I'd like to know what polymer their "standard rubber" is.

You've brought up one of the sticking points for owners of Scepter MFCs. The Scepter gaskets are not available by normal legal means to civilians.
It would be nice to have a steel die machined to stamp out a bunch of Viton gaskets that would fit the Scepter lids well. Otherwise a razor blade would be fine for onesies but it might waste the full sheet of material.
 

cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
Viton and rubber seals are readily available, there is a gentleman in FL (posted here on ExPo) that has the Viton in stock for $4 each (shipped), the rubber was ~$2 as I recall.

Most gasket companies (several here in SLC for example) can make these in just a day or two out of rubber or viton. I got quoted ~$5 each to have viton ones done locally, they should have their first batch done early this week.

I just happen to have the blueprints handy for any looking, all you had to do is ask ;)
 

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teotwaki

Excelsior!
Viton and rubber seals are readily available, there is a gentleman in FL (posted here on ExPo) that has the Viton in stock for $4 each (shipped), the rubber was ~$2 as I recall.

Most gasket companies (several here in SLC for example) can make these in just a day or two out of rubber or viton. I got quoted ~$5 each to have viton ones done locally, they should have their first batch done early this week.

I just happen to have the blueprints handy for any looking, all you had to do is ask ;)


Wow! You are one impressive dude!!
 

Tucson T4R

Expedition Leader
Ok when fueling up for upcoming trip on Monday I noticed I have been impacted by this. :Wow1:

I have color coded cans, red for Gas and yellow for diesel. All my caps have grey colored gaskets so I assume they are already Viton. But both my gas and diesel caps have the retention rings broken off and the gaskets can just fall out now.

This thread talks a lot about different gaskets and where to get them. I'm not sure where I can get replacement caps with the proper gaskets.

Any suggestions?

They still seal this way but the gaskets are loose and have to be positioned when closing the caps now.
 

cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
...This thread talks a lot about different gaskets and where to get them. I'm not sure where I can get replacement caps with the proper gaskets.

Any suggestions?

They still seal this way but the gaskets are loose and have to be positioned when closing the caps now.

With the exception of gaskets, spare parts are getting pretty hard to come by. Canadian based Scepter dealers absolutely won't ship to the US. I've got a lead on some spare cap assemblies (cap/flange/gasket/strap), I'll be sure to post if/when they ever materialize.
 

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