TOPIC: Gas left in carb a year test done..

This was a new carb I bought for a CT70 Minitrail mine, and wrong intake bolt pattern. But I had to do a "test" "leaving gas in a carb 2 months turns to crap". Calling BS, and always did. I've never ran anything "gas out carbs" since the Minibike days 6 decades ago. Only if a good pickle and going into storage for years motors mine.
This gas was 10% ETH 40-1 2 stroke mix, with Stabil (red) and sat 3 months in the shed as used chain saws/blowers. Filled the bowl the new carb it and let it sit on the bench 9 more months. I'm still hearing stories about "ETH yellow snot" as tried that too and never showed. Now clue me that and if a story?.. bring it on.
Anyway M/T thought gas, but gone. Little lingering fresh gas smell,zero film the float as the bowl. I could sell it tomorrow as "new" Pix say it all........

Your carburetor doesn't reflect the actual usage conditions that would impact most power equipment.

The part was brand new. It never had to process fuel that could have had some water or crud in it.

The new carb probably was manufactured with rubber designed for modern alcohol laden fuels

The alloy used for the body may even be corrosion resistant

Most equipment gets stored outdoors (covered or uncovered) where it is exposed to humidity and wide temperature swings

Your carb had the openings exposed to the air - so the fuel in it could readily evaporate out of it - before souring

The oil and StaBil in the fuel don't reflect the stuff that runs straight gas and stored without a fuel preservative.

"The part was brand new. It never had to process fuel that could have had some water or crud in it."

THAT WAS THE POINT TEST! AND it WAS YEAR OLD GAS!

I under stand that. But thats those using bad gas and no filter much less maintenance as careless. I'm simple talking good gas will not harm a carb bowl and turn to crud in 2 months...

"Maintain low tones." - Beldar Conehead

Back in 2010 I worked on a guy's 2006 Yamaha 15hp 4-stroke on an aluminum fishing boat. It wouldn't start for him.

He had trouble with water in the gas, so I had to pull the carb and flush/clean it. Nasty congealed fuel/water mix. The carb was full of white corrosion products, from use of ethanol fuel. I expect that fuel was sitting around for quite a while and may have even sucked up some water. Had to brush/scrape all the deposits off the carb's innards.

At any rate, I told him to be sure and use Seafoam or a stabilizer such as Sta-Bil or Star Tron. He hasn't had any fuel problems since.

Thing was, the carb (and entire motor) were so clean you could eat off it! But the inside of the carb was a Nasty Critter.

Imagine leaving unstabilized Gasohol in your lawn tools for a year, it'd be a nasty mess too. Remember when you could fix a plugged-up carb on your lawn mower or weed whacker? Now they're virtually unrepairable after the Gasohol mix gets done with 'em!

I always use stabilizer in my lawn tools and in my outboard test fuel tank. I have also forgotten, in the past, to run my mower or weed whacker out of gas for the season and they've sat with stabilized ethanol-blended fuel in them for the entire winter outside.

Guess what, they started right up in the spring!

I have a Cenex station nearby that sells straight gas, that's what feeds all my equipment now, including my Nissan PU. Everything runs better without that alcohol cr*p in it!

I have used Briggs & Stratton fuel stabilizer in my old Trooper that sits a lot, and all the yard stuff, for quite a few years now. Claimed to protect up to 3 years at the right dosage. Seems to work great and it wasn't really expensive when I got a bottle off Amazon.com.

I tell everyone I can to use straight gas if they can find it, and stabilizer in their small engines. All the corn-squeezin's have been bad for a lot of engines, but good for the mechanics' pockets!

BTW I expect the results on the carb wouldn't have been quite so good if ethanol-laced fuel was used. But it'd be a shame to mess up that purty new carb!

I reckon the lesson learned here is to use Seafoam or a stabilizer no matter what, if you have to use ethanol fuel. And even straight gas needs stabilizer if it's gonna sit for a long time.

Cheers..........ed

Ed, I of course agree with you! We (as Thom) seen it all! And that was 10% ETH gas too.

Let me reiterate here again. Not trying to start an argument with all the MANY variables that could apply but I did try to duplicate real conditions. I wanted to do this because I had a new carb. Chinese knock off for small Honda, so not OEM. No way to test with a used carb as it would be discolored. It was ONLY done to see what would be left in the bowl. And I THOUGHT SOMETHING would be left and some "crud" but found nothing and I was surprised! And thats all I tested it for.
And I'm going to shed some incite questions here and another forum. I've fixed small engines (and large) all my life and sure have seen some junk and some would knock ya over taking a whiff sour gas. Heck, just fixed a 1990 Tohatso 5hp that would not stay running. Bowl clean, but the jet was plugged solid with something I would have had to drill it out, so got a new jet and fixed. Plus I put a inline filter on too. And anything I have gravity feed had better have a filter and shut off, or its gonna get them. On the carb being open to air, well its the same as on a motor without a air filter (boat motor). Float bowls are vented in some fashion, why you need sooner or later a pump up/bulb prime unless gravity feed and no shut off. And here PNW aint the driest place on earth, and shop goes 50 overnight to 70's day.

I run "Gasohol" even though just up the road a Casino owned station ETH free, 20 cents more gal. I've simple had no problems. I DO "Stab" gas when bought and have a long time. Anything sitting say winter get vents closed or boats in hull tanks get tape over the vent for moisture. All outside shed lawn stuff will sit and starts right up all spring.
Case in point my 22 year old Generator. Not needed last 3 years as no long power outs. And all I ever did is fall suck the old gas out (smells fine) and burned in the Van. New stabbed in, 5 gallons, fired up warm, and shut off and gas off and new oil and put away. Still starts 1 or 2 pulls year later. Same as mowers and rest.

I've tried other test too baby food jars, sealed, vented lid, and open and all different kinds mixtures and nothing was ever found sitting for months. Heck, even did a "snake oil" test extra water in ETH fuel and tried both MDR "Waterzorb as "E Zorb, and shook it up and water dispersed. Will settle out a bit in time, but shake it and gone again and will burn in a motor.

Now I'm gonna do anther test with that same now year old gas still in the 3 gallon can and 1/2 full baby food jar, stab a hole in the lid, put it outside here rainy PNW in the weather, but out of the rain and wait until spring and see what happens. Follow up that later.

And on snake oils? I don't care Stabil, either one, Startron, Seafoam but do SOMETHING all gas as works for me and have since the 70's with my XS Switzer that sat out midwest all winter. And as diff regions all us, seems humidity in the south and heat might have something to do with "watered gas" as hear many stories there "chit gas". I dunno. And just last week buddy mine took his wifes car the wrench here as running rough. Diesel motor. Said try some injector cleaner first or injectors need work. Asked me and said put a full can Seafoam into 8 gallons. Well, it cleared itself up. Also a fan Techron "concentrate", not injection cleaner but ok that for treating gas occasionally . Old dude across street only used his ATV hunting once a year and it ran terrible one fall. I dumped a heavy dose Techron in it and well, cleared up. So yes, some stuff does work. Just wish the "uninformed" knew what to do, but OK me as does keep up the bucks coming in to Mechs to "fix". Leave your mower sit outside in the rain all winter no "preventive maintenance" and I'll see ya in the spring..........(and I'm not talking you guys here as know better than that anyway)

Well I had an on-going battle for about two years with rotten fuel and my 8 hp 4 stroke Honda I use for fishing. Small black particles and the usual water/alcohol crap in the carb. Wait I use it 2-3 times a week. It don't go bad that fast. sure. I found out the primer bulb with Honda on the side that was new with the engine had rubber breaking down from alcohol. Honda said impossible. So I cut it in half and had black on my fingers. If I were you I'd just consider myself lucky. I also sell small tractors. At least 80% of my intake is for alcohol and fuel problems. Clean the carb and tank and they run like new. Well that being said I run my engines dry when I'm done. Be real careful filling tank to avoid dust and dirt and just smile because all is fine when I use stabilizer in the shit they sell as gas. Check this out. pure-gas.org/

That looks like a carb that would fit my 1980 Yamahatchi 250cc Exciter cycle. Haven't run it since '10 but never had a problem lettin' it sit for years with a full tank (non ethanol reg gas)

robert-lorigan wrote:

Well I had an on-going battle for about two years with rotten fuel and my 8 hp 4 stroke Honda I use for fishing. Small black particles and the usual water/alcohol crap in the carb. Wait I use it 2-3 times a week. It don't go bad that fast. sure. I found out the primer bulb with Honda on the side that was new with the engine had rubber breaking down from alcohol. Honda said impossible. So I cut it in half and had black on my fingers. If I were you I'd just consider myself lucky. I also sell small tractors. At least 80% of my intake is for alcohol and fuel problems. Clean the carb and tank and they run like new. Well that being said I run my engines dry when I'm done. Be real careful filling tank to avoid dust and dirt and just smile because all is fine when I use stabilizer in the shit they sell as gas. Check this out. pure-gas.org/

I'm with ya on that but I'm blaming "new junk" is useless. Thing is I have a 28 YEAR OLD Bayliner 20' Cuddy/125 Force and sits salt 3 months year slip. Damn thing don't care a bit what gas used and always as far as known, 10% ETH. Still has original OEM fuel line (in hull tank) orig primer bulb. I only have to bulb "Prime" in the spring and fires right up and not primed again all summer. I do get a little black carbon on the paw, but still.."Flexible". And the sun hits the bulb daily wet well. And I just did last year a old gent here with one the stiffest bulbs ever saw! And new 12 years ago (new Nissan 20, small boat) and always parked covered. I just hack sawed in 1/2 and zero deterioration inside. But the rubber is like a brick...

Anyway, doing a new "mad science off season now test" Baby food jar with that same old stabbed gas a year ago, ETH mix, 40-1 oil in it. Stabbed a hole/vent in the top and set out outside, ALONG with a open glass same. Let ya all know when I find something.

I did something like this a year or 2 ago. Had a small tank with contaminants in it, poured the majority of it into my jeep, and then the last quart or so into a large glass pickle jar I had but used a coffee filter or 2 to get the crap out. Sat in the garage (detached no heat or a/c) sealed for 3-4 months over the summer - I actually forgot about it.

By end of summer, the color had totally changed to a murky brownish yellow, although the smell didn't change much. there was also no additives in it (other than what came out of it with the pump), so I'll be curious what happens with yours.

BTW, all that said, I've only had 1 Ethanol related problem, and that was in an old lawnmower several years ago that I forgot to winterize. I agree that, for the most part, if you take care of your equipment and use the various stabilizers, it will do OK. I don't think it will do as well as real gas, but since that's hard to get here on LI, ethanol it is!

Gas in the glass is half gone, and looks like some separation on the bottom. Been drizzling all night and maybe picking up moisture. I'll know more tomorrow...

OK...results. Nothing yet the vented baby food jar, but the open glass? Sucking water up fast! I just refilled it now third time and going to let that evap and see what ends up there. Heres a pic...

That's ugly....