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Fuel Tank Additive?

Featured Replies

Since retiring, my WRX only gets driven ever week or 2, and then often just a few miles. Wondering if a tank additive would be a good idea. Thinking either Sta-Bil, or, leaning more to just a product like HEET. I think now there are 2 types of HEET???

 

would you guys use anything?, what?

1 hour ago, 1 Lucky Texan said:

Since retiring, my WRX only gets driven ever week or 2, and then often just a few miles. Wondering if a tank additive would be a good idea. Thinking either Sta-Bil, or, leaning more to just a product like HEET. I think now there are 2 types of HEET???

 

would you guys use anything?, what?

It won't hurt anything by adding it but could have catastrophic impacts if the gas goes bad. I keep it in my motorcycle, old truck, and all my other small engines just in case.

Shelf life of gasoline is generally 3-6 months.

I use Seafoam. It's cheap and has worked fine. My truck sat for almost a year and started right up and ran just fine.

I use Stabil 360 if I know it will be more than 3-6 months until the next drive or tank refill. Between 9-12 months I'll usually siphon down the tank and load the old gas into a daily driver and then fill the stored vehicle with fresh gas and run it for a 10-15 minutes. Most of the cars I store long-term are air-cooled so no issues with engine coolant and corrosion worries, only stagnant fuel.

Do you have any non-ethanol gas close by? Non-ethanol is the gold standard.  Landscaping equipment managers and boat owners go that route and have no love for additives.

More anecdotally, I've used Stabil and my outdoor equipment never worked any better over doing nothing. I may be mis remembering but I thought GD mentioned years ago treatments aren't nearly as good as their reputation. I remember someone talking about it because it was when it wasn't doing my property equipment any good. 

Here in Australia our top RON rating is different to US RON ratings. I have left a full tank of 98 in my turbo Vortex for up to two years without issue. Things may differ if I left some air in the tank with the fuel - I don't know 

  • Author

briefly searching, looks like I'd have to drive a coupla counties away to find E0. And I don't know if they'd have premium E0.

a week or two is not going to be long enough to worry about your gas going bad. even a month or maybe two is not really a huge issue...

if you were going to store the vehicle for 6 months or longer, then maybe yeah - might consider taking precautions.

for what it is worth, i dont drive mine every day either.. it could easily be a week or more without moving the car...

I would be more concerned with the battery running down than with the gas going bad.

  • Author

yeah, I think if I do anything, I'd lean towards a gas dryer - just thinking about the temperature/humidity cycles until I get to that last few gallons...wait

 

as I type this, I realize a good approach may be to just fill-up sooner! less atmosphere 'head space' .

 

I think I'll start refueling at 1/2 tank and see how that goes.

  • 2 weeks later...
On 3/4/2023 at 3:33 AM, 1 Lucky Texan said:

briefly searching, looks like I'd have to drive a coupla counties away to find E0. And I don't know if they'd have premium E0.

Have you got Ethanol blended into all your fuel ??

Met a friend at a local airfield in Bridgeport, CT as he was flying by and learned that they sell non ethanol fuel.

  • Author

it would be tricky for me to get E0. Where I live, the 5-7 counties around me are considered 'non-attainment' for reduction of pollution or w'ever.

I live in a very VERY small community where people drive short amounts, maybe 1-2 miles per trip without warming up their engine. Some residents leave for 9 months of the year before coming back to do the same amount of driving. I've had about a dozen so far come to the shop with fuel related issues, usually rust deposits that make their way into the fuel injectors.

Additives are a tough sell for me as far as gasoline engines goes, I wouldn't bother pouring one in *unless* your fuel tank is below 1/2 and you plan to leave the machine parked for a year. Only then would I pour in a methanol based alcohol (known as HEET in the US). The purpose is to help absorb moisture that will accumulate In the tank during storage... I've had one customer that did this excessively and the alcohol content eventually became too much for the engine to manage and burn on its own.

If you do need to drive the machine every couple/few weeks, it shouldn't be an issue. keep the fuel tank topped off on every other drive, and forget additives unless you know it wont be used for a long period of time. Gasoline does degrade, but from your use case it sounds like that shouldn't be too much of an issue.

More importantly if, during the times you *are* driving it, as long as the car gets to operating temperature and it gets some small amount of highway driving it should be A-OK! Otherwise, keep It stored. I've seen engines that slowly accumulate moisture from short drive cycles that they are effectively 20%ish water in their engine blood, no good.

There's a mechanic who has a lot of followers on Youtube who reviews many of the fluid additives and makes a lot of sense.  Greyhaired energetic fellow.

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