Gas stabilizer

[Muse]

I've been driving especially little during the pandemic. For a while, almost none. Was driving maybe 1000mi/yr before, now maybe 500. I was posted here I should add stabilizer to the gas. My last fill-up was Jan. 6, 2021 2022, so 6 months ago. I've got maybe a bit under 1/2 tank right now in my 1997 Mazda 626LX 2.0L sedan (has 34k on it).

So, this morning I ordered a 32oz bottle of STA-BIL 22014 Stabilizer off Amazon.

I read some instructions saying I should add 1oz for every 2.5 gallons of gas, but to fresh gas, and then keep the tank 95% full to prevent water condensation.

I have been taking my car for a 10-20 mile trip to Costco and back (stopping at Trader Joe's near the house) every 2 weeks.

I always get my very occasional fill-ups at Costco, and that's all the driving I've been doing for the last year+.

So, I'm wondering how to proceed. Put some STA-BIL in now (when it gets here, in a week)? Wait until I fill up? If I fill up now, 1/2 the tank won't be fresh regular gas!

I also have some Chevron Pro-Gard Progard Fuel Injector Cleaner with Techron additive (bought a case some years ago), that I've seldom used. My cousin's husband said add a container to a full tank of gas, then drive 50 highway miles. I seldom drive 50 miles straight, but may this summer.

That 32oz bottle of STA-BIL, the instructions say to use it within 2 years. I wonder how important it is not to go over 2 years with that.

Thanks for suggestions!

 

[mindless1]

My last fill-up was Jan. 6, 2021, so 6 months ago

1) It isn't 2021

2) The stabilizer has to be put in before the gas ages

3) It's better on the vehicle to run it more often, but two weeks isn't extreme. I'd have a battery float charger on it as sitting this long over and over between recharging (from alternator) will age the battery otherwise.

4) At this rate of consumption I wouldn't fill the tank, instead half tank at most. I realize some fuel pumps run hotter with a low tank but there is a middle ground since the pump is usually low in the tank.

5) I would drive up the current tank of gas, with some techron cleaner in it, then try to keep your tank about 1/3rd full and if available in your area, get ethanol free gas as it has a much longer storage life.

6) Once you get the fresh fuel, then put some sta-bil in it.

7) Water condensation isn't much of an issue on a remotely modern fuel system that's sealed and vac purged. That direction is more for storage tanks where people pour some fuel out, drawing in outside air and let it sit long term, repeating this over and over.

 

[Muse]

Doh! Yeah, Jan. 6, 2022 was last fill-up.

I do have harbor freight float charger on the battery between drives. That was before AND after buying new battery, 2 months ago (old one was 8 1/2 years old!).

I'm trying to understand what you're saying here...

Pour "some techron cleaner in it," you mean add, say, 1/2 a bottle of techron into my current 1/2 filled tank and then drive in my usual fashion (10-20 mile trip, once every two weeks) until the tank is near empty, then fill 1/3 to 1/2 full of preferably ethanol-free gas and add appropriate amount of Sta-Bil, i.e. 1oz/2.5 gallons gas?

 

[mindless1]

^ Yes, put 1/2 bottle of techron into current 1/2 tank. As long as your 10-20 mile trips aren't going very slow, this is enough time in summer to warm the engine up... maybe even going slow. There is still some merit to doing the italian tuneup, get it out and give it a lot of RPMs for 50 mi, but this is less and less applicable with semi-modern engines that are used on a regular basis and get timely oil changes.

Yes to the rest, though I don't remember the sta-bil ratio, and there is an exception. If you live where you might be subject to highway accidents that could be backing up traffic a very long time in extreme weather, you might want more fuel in the tank to keep HVAC working till the road is cleared to leave.

 

[Muse]

I might visit a friend ~100 miles north sometime in a couple months. Heat is possible, but I'll try to avoid 100F days. The recommended radio for STA-BIL, from that Amazon page is 1oz to 2.5 gallons gas.

So, I'll add the 1/2 container Techron and won't gas-up until close to empty (I have gas cans, so I can carry just in case a gallon or more... but boy, that's old gas! ). Maybe OK to clean skate bearings, though.

Thanks!!!

 

[Muse]

@mindless1: What's the reason to keep the tank 1/3 full? Don't do the typical full fill, only pump in, say, 5 gallons (and adding 2oz STA-BIL)?

I'll see if Costco has ethanol free gas, but I kind of doubt it.

 

[mindless1]

At the rate you are using gas, if you only keep it 1/3rd full, the gas doesn't get as old before used and replenished with fresh gas. The trade off is you have to put gas in 3X+ as often but that's better for the fuel system than having varnish buildup. I just wouldn't run it near empty on hot days since being submerged in fuel does help keep the fuel pump cooler running.

 

[Torn Mind]

The reason fuel in mower tanks(main use of Stabil) goes bad over prolonged storage is because of water. Since you are still drawing down the fuel in the tank every two week, water accumulation hasn't really been able to happen. If you are that concerned for your car, just put in a partial bottle of HEET.

I snagged a throwaway mower after spotting one while delivering pizzas. After work, I went and took the gas mower into my Mom' Toyota Matrix. Dumped the tank clean, put new gas, and it fired up.

Alternators and brake lines are a couple other things that fail while a car sedentary. I believe the heat from braking is why regular brake fluid does not rust out for years if the car is regularly used. If the car sits for months, then the water can really start corrosion without interruption.

Humidity kills alternator electronics.

 

[RLGL]

The reason fuel in mower tanks(main use of Stabil) goes bad over prolonged storage is because of water

AIR not water

 

[Torn Mind]

AIR not water

I've had to drain bad fuel from a vehicle that sat too long and had a leaky air seal somewhere. In the containers(like a gallon Lipton iced tea bottle) used to store the extracted "bad gas", it's obvious to see that water got "pulled in" from the atmosphere thanks to the ethanol as the gas was on top and the water on the bottom. Using a cheap siphon, the leftover gas was still viable to use for mowing but the water component obviously was useless.

There's the "varnish" and crap that also comes from ethanol fuel but that's more of an issue for mower carbs with small holes rather than big vehicles with fuel injection.

Mid-Atlantic is humid in summer, so gas will go bad in my area.

 

[RLGL]

I've had to drain bad fuel from a vehicle that sat too long and had a leaky air seal somewhere. In the containers(like a gallon Lipton iced tea bottle) used to store the extracted "bad gas", it's obvious to see that water got "pulled in" from the atmosphere thanks to the ethanol as the gas was on top and the water on the bottom. Using a cheap siphon, the leftover gas was still viable to use for mowing but the water component obviously was useless.

There's the "varnish" and crap that also comes from ethanol fuel but that's more of an issue for mower carbs with small holes rather than big vehicles with fuel injection.

Mid-Atlantic is humid in summer, so gas will go bad in my area.

Even with a fuel stabilizer, condensation will form if the tank is not full.
The "varnish" would have happened even with the old leaded fuel and also with non-oxy fuels. This is one case where a fuel stabilizer will help. For my yard equipment, I only purchase a 60-day supply. A fuel stabilizer is added prior to filling the container. I also drain the carbs and shut the fuel supply off at the end of the season.