Why does starter fluid cure my no start? What is the issue?

airbiscuit · Dec 1, 2020

FarmaBro said:
I would check that the choke plate is correctly returning to the closed position when the engine is off.

TractorGuy said:
This would be my first suggestion also. Make sure cable hasn't slipped and choke is working as it should.

A couple years ago, I bought a brand new Snapper lawn tractor that acted like yours. I even put a check valve on it to keep it primed. Dealer said they just run lean. I took the air cleaner off and discovered the throttle/choke cable was mal-adjusted and didn't close the choke completely. Adjusted it so the choke would close, and problem solved.

tomplum · Dec 2, 2020

airbiscuit said:
A couple years ago, I bought a brand new Snapper lawn tractor that acted like yours. I even put a check valve on it to keep it primed. Dealer said they just run lean. I took the air cleaner off and discovered the throttle cable was mal-adjusted and didn't close the choke completely. Adjusted it so the choke would close, and problem solved.

Just like the man said, the choke must close for a cold start. Likely a simple cable adjustment. You can feel the choke lever to check if it is closing. The choke however isn't supposed to return to the closed position when shut off on most engines.

paulfun9 · Dec 2, 2020

Tinhack said:
It probably had a sheared flywheel key. Most likely from someone using starter fluid. :laughing:

One backfire is enough to shear a key and ****** timing. That's all it takes to make an engine hard to start. It all begins with a bad plug, fuel or air problem. Starter fluid is NOT a fix. :laughing:

If one backfire from starting fluid is enough to shear a key then one backfire from gasoline in the system is also enough to shear a key. One stall in heavy grass would also shear a key telling me the engine is junk from the start.

Choke on my mower hasn稚 worked in years so the cup holder is now the starter fluid holder. Spray a quick shot at the air cleaner and it fires up every time. About ten years now and not a single backfire, not a single broken key or any ill side effects.

Maybe if you don稚 spray starting fluid into the carb like it was water being used to often a fire you wouldn稚 get backfires?

user.69169 · Dec 2, 2020

Orfice and burner go in top toolbox drawer, never know when you gonna need.

Only change I make when somebody steals dis one is rubber hose dats very flexible in cold.
Sure hope whoever steals leaves brown bottle, it's last refillable I got.

ray66v · Dec 2, 2020

I have a Husky, with a 23 hp Briggs that acts the same as the OP's tractor.

The choke is closing all the way. And, I replaced the fuel pump. No joy.

If it sits for more than a day, it cranks a long time.

Sound like a fuel issue right? So, I installed an electric fuel pump. Problem solved? Nope, it didn't make any difference.

Acts exactly the same way. Starts, and runs fine if you use it every day. Cranks forever, if you don't.

At this point, I'm considering using the electric fuel pump to make a fuel injecting primer system.

Tinhack · Dec 2, 2020

paulfun9 said:
If one backfire from starting fluid is enough to shear a key then one backfire from gasoline in the system is also enough to shear a key. One stall in heavy grass would also shear a key telling me the engine is junk from the start.

Stalls normally don't. If you hit a stump or anything to cause the blade (crankshaft) to stop suddenly, the flywheel will try to continue spinning. That's what sheers the key. In a backfire, the crankshaft is forced to turn backwards while the flywheel is still trying to move forward. The key shears to save the crankshaft. That's why the key is made from very soft metal. The key is also the ignition timing index.

The shearing may or may not be complete. I've seen keys sheared only about half way through and still allow the engine to run. They'll be hard to start and won't run with full power but they will run. That's because the ignition timing is retarded. If you take that half-sheared key and turn it around to advance the timing, you'll gain about 10-15% more power. It may be hard to start there too but it will run like you've never seen before. The factory timing is a compromise to allow easy starts. That is in addition to cam lobe timing. But I don't even want to get into a cam discussion here.

I used to race Karts. I ran in the Super Stock class running on pure Methanol. I built and tuned my own engines. What started as a stock 5hp Briggs & Stratton was putting out about 10hp on race day. When your rear is in a seat about 1" off the ground, 80mph feels like 280. That is a rush! That was at the Mid-Ohio track. The usual Kart tracks will only allow about 30-40mph in the straights before the first hairpin.

Sorry to drift. Those were the days.

All I'm trying to say is if you need starting fluid, something is wrong. The engines were not designed to be started on ether. (Some are but not small utility engines.) The problem can be fuel, air, ignition or any combination of them. Also, valve clearance can effect starting. This is part of a fuel/air combination. You would be surprised at just how complicated the engineering of these small engines can be. It's not just gas and oil that keeps them running.

crazyal · Dec 2, 2020

I think every riding mower sold today has an electric fuel solenoid. If the valve is slow to open it'll cause long start times or not starting when cold. It's possible that once the motor starts the extra voltage from the alternator is enough to open it or the vibrations from the running engine will jar it loose. When warm the engine will spin faster when starting since there's less resistance which will also mean a higher voltage. A warm solenoid may not stick. After the choke this is what I would look at for a fuel issue with a riding mower.

airbiscuit · Dec 2, 2020

I think the newer small engines all crank longer before starting because of that fuel shut off solenoid, emissions settings, etc.

Ford850 · Dec 2, 2020

airbiscuit said:
I think the newer small engines all crank longer before starting because of that fuel shut off solenoid, emissions settings, etc.

I had a JD mower with a Kawasaki engine that cranked a loooong time before starting. I learned to bump the fuel lever up to midway before starting which helped some. I think the OPs Toro model came with Kawasaki, Kohler, or a self branded Toro engine so depending on which he has it could be an inherent issue too.