Lawn mower troubleshooting: won't start, except...

Factual Questions
1

So I bought a new mower last year. I was stupid and didn’t empty the tank fully before the season was over. When the new season started, I opened the tank and flipped it, but it seemed bone dry on the inside. I was a bit mystified by this, but didn’t give it too much mind. I filled it up, mowed, everything was happy go lucky.

Except… now, every time I get out my mower, it won’t start unless I flip it over again (well, and of course right it afterwards). I can try it over and over again, nothing. As soon as I flip it it starts like a dream, every time.

I have to figure there’s something in the tank that I’m dislodging but just flipping it doesn’t seem to get it out. I got a turkey baster but it can’t pick up any liquid in there when it’s empty. If there’s water in there, I’m not sure how to get it out. This problem has lasted all season and hasn’t gotten any better (or worse), through repeated fill-ups of gas.

Any thoughts of something I could do with the thing?

2

Just a WAG here, but there might be water in your tank. Get a can of HEET and mix that with your next tank of gas. It just makes water mix with gas so you can burn it.

Otherwise, you’re going to have to pull your carb and clean it. Modern gas doesn’t gum up like it used to, but it may have and clogged your jets.

3

Through some casual Googling, I read that HEET isn’t good if your state uses an ethanol blend gas (mine does). No ethanol gas is available, should I be buying that for my mower? I never really thought about it.

4

Stuck carburetor float?

5

I’m pretty sure one of the car guys here said that Dry Gas, which I presume is the same as HEET, wasn’t necessary when using an ethanol blend, as the water will mix with the ethanol anyway.

I wouldn’t buy HEET until you get a denial of that from someone who knows what they’re talking about.

6

I’ll bet what’s happening is that when you flip the mower over, you’re causing gas to leak out of the carb bowl and down the throat, essentially doing the exact same thing as hitting a primer. There’s probably some junk in the carb that may or may not be related to the old gas. Since you can get it running, you could try a pour-in carb cleaner additive, or else what you probably will need to do is dismantle it to a point that you can clean the carb with some carb-cleaner spray and a rag.

7

If yours has a primer bulb, you might try pushing it a lot more times than the instructions say.

On every mower I’ve ever owned that had a primer bulb, the instructions always said “Press Three Times”. This always required ten or fifteen pulls on the starter cord (or a lot more, sometimes), to get the thing to start. Luckily, I found that pressing the little bulb fifteen or twenty times guaranted a first pull start. I wonder who writes these instructions.

8

I know a lot of scaredy-cats will whine, but just use **ether **(aka starting fluid) with any pull start device. Works every time…

9

You have the same problem I used to have with my bike if I didn’t drain the carburetor in the fall. The old gas turns to turpentine or varnish (or smells like it!). The float in the carb is stuck and so does not allow the carb bowl to refill. Shaling the lawnmower upside down loosens it enough to run until it sits for a while. I could get the same effect by tapping the carb bowl with a hammer.

There’s probably some carb cleaner or something you can mix with the gas to clean out the gunk.

10

IANACarGuy, but I do, and have, changed over small engine lawn equipment twice a year for a couple of decades. What I do is have a “MayDay parade” (named after the Soviet propensity to pull out all their tracked military vehicles every may 1st, for a parade, but I did it twice a year) when one of the small-engine crap was a tracked snow-blower my father stuck me with. Ohh, just about as useful as a T-34!

The May-Day parade is when I started them all up and ran them out of gas, regardless of how much was in them (and may first is my target date for it, too), then brought out the new season’s machines and started them all up. Since I’m rather stingy on the gas I put in, in the first place, most won’t run an hour. Run them 'til they run out. Don’t fill them again. Gas 'em up, and start 'em up in the spring. As long as you are buying good quality equipment [I highly recommend MTD and “Briggs and Stratton” as the brands to buy] in the first place, they should start right up. I never experienced a problem with ANY one of them, until it was at least 12 years old, and even now when it’s 16 yrs, a quick squirt of ether-based starting fluid works for the first start, and you don’t need it again.

Run everything you are putting away until it runs out of gas. No need to put “preservatives” in there. Just run them all out, and park them. Even at today’s gas prices, that’ll cost you maybe half a buck per machine, assuming you were properly only filling the machines as you needed them. Fill 'em and start 'em next season. If they won’t, give 'em a squirt of ether, and try again. I’ve never had that fail, unless there was an underlying mechanical problem.

That’s what I do, and it’s worked just fine for machines I bought last year, and it’s been working fine for machines that are over 2 decades old. And worked for one which my father left out under a bad tarp for 2 decades, and it didn’t take me much work to make it run, even after 2 decades of leaving it out in the weather. I was shocked that that one still worked. Briggs and Stratton. Buy that name. Fairbanks-Morse is good, too, but try to find those in any machine smaller than a nuclear submarine, these days.

11

Ah, interesting. Something like Sea Foam might work?

Cheshire Human: I’ll definitely run her out of gas before the end of THIS season, but, the damage seems to be done. I’ve run out of gas during mowing since the problem started happening, and it didn’t fix anything.

12

For off-season storage of power equipment and gasoline, I’ve had good results for many years with a gasoline stabilizer called “Sta-Bil”. Use according to directions on the label.

13

I once had a mower that the gas dried up in the carburetor, stuck the float. I took it a part, cleaned it and then it started ok.
Since then I use StaBil in my lawn equipment, chain saw, ATV, and 2 marine engines for storage. No more problems.
Today’s gas that contains that snot called ethanol is real bad to give storage problems but StaBil also takes care of it.

14

That was how I prepare them for storage at the end of the season. When you already have problems, my only suggestion is what I do:

:dials phone:

Ken: Hello, Ken’s Small Engine Repair, how may I help you?

Me: Hi, Ken, it’s me, Cheshire Human, again. Remember how you fixed my snowblower last winter? The lawnmower is doing the same thing.

Ken: I can come over Thursday afternoon. Will that do?

Me: Great! I’ll be here…

:frowning:

15

You mean I don’t have to get the lawnmower in the car? They will come to my house? Sold!

(Really isn’t sarcasm, part of my reason for this thread was figuring I’d have to take the thing to the shop myself.)

16

Some will come to you. Ken is in Central NY. I don’t think he goes as far as you are. :smiley: You’ll have to look around for someone local.