Drop 1 quart of methanol for every 10-15 gallons of diesel and you will never have any gelling problems.
No gelling problems...but now you have something in your fuel that emulsifies water into the fuel. I'd rather have a proper demulsifier (if needed) that helps the water fall out so it can be collected in the fuel/water separator before it gets to my expensive common rail type injectors.
I'm the kind of person that likes a large amount of data to make decisions. That in mind, I've actually called PowerService and Howes about this (Stanadyne never returned my calls).
I did also find this link.
http://www.ezoil.com/resources-diesel-fuel-additives-emulsification-vs.-demulsification
What I like about this link is that, even though it's part of a product sales site, they given a very even and broad answer to the question about emulsification/demulsification. Just like everything else in life, there is no "best".
There are pros/cons to both emulsification and demulsification additives and processes. There is no "best" answer for all applications regarding removing moisture; you need to assess the conditions of fuel, and operation, storage, etc.
After speaking with a chemical engineer at PowerService, I've decided that it's not worth worrying about. The big three (PowerService, Howes and Stanadyne) all make good products that are tailored to specific conditions. The better you research your application and define your conditions, the easier you'll find a product that will work for your concerns. I used to believe that demulsification was the only answer to all things; now I realize that's not true at all, and there are challenges with demulsification I was not aware of until I researched it.
Funny thing is that anti-gel additives in diesel supplements don't assure a final value of "x" degrees of anti-gel performance. What they do is "add" to the value of the fuel already being used. Example:
Say you choose Stanadyne and their product offers a 25 degree improvement in cloud-point. What that means is that whatever fuel cloud point exists, it will improve by 25 degrees. If your chosen fuel source clouds at 20F degrees, the additive will improve it to -5F. If your fuel is only good to 50F degrees at cloud point, it will only drop to +25F deg with the additive. Starting with winterized fuels helps the additive product take your cloud point deeper into the cold range. (note: cloud point, plug point, etc are terms for the same conditions). The anti-gel additives suppress the cloud points by a magnitude of improvement, not final value. If you read the marketing info closely for these products, you can even see they call them "improvements" and not stagnant "values". Also, these improvements are based upon proper use of ratio; more or less product in mix will alter this CPP ratio.
Some of the products are what I'd call "full service" additives; they address not only gelling of fuel, but have additives for lubricity, cleaners, anti-foam agents, cetane, etc. Other products are only specific to one or two tasks. You need to carefully research the choices from each brand to know what you're getting.
Example: the "silver bottle" (Diesel Kleen) from PowerService is similar to their "white bottle" (Diesel Fuel Supplement) in terms of addressing lubricity, cleaners, etc, except that the white bottle has the addition of an anti-gel additive. That anti-gel additive takes up space in the formulation; leaves less room of other things by volume and solubility. Therefore the "silver bottle" can hold more cetane improver and detergent, because it has zero anti-gel in it. The white bottle has less cetane improver because it has the added benefit of anti-gel. IOW - the more you tasks you assign to the product, the more of a compromise it becomes.
Example: Stanadyne has a "full service" product called "Performance Formula". But they also offer stuff that addresses singular things as well.
And again, "full service" products are a nice compromise, but they don't do anything "best". They are a good jack-of-all-trades-and-master-of-none approach.
Caveat Emptor!
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