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

[airbiscuit]

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

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]

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]

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]

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]

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]

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]

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]

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

 

[Ford850]

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.

 

[ForumJunkie]

Shop said its the choke.

I have no idea how to fix that since you can't even see it (like on a car)

 

[ray66v]

Follow the cable to where the outer part is clamped, and the inner part comes out to move the linkage.

Loosen the screw that holds the outer part of the cable, and move the linkage by hand. You will feel the choke stop, when it's fully closed.

Re-tighten the clamp so that the cable is in the right position to allow you to reach that point.

Adjusting the choke so that it fully closes, can be the problem. It was on mine when it was new. But, a couple of years later, it didn't matter if I made that adjustment.

I will replace the fuel solenoid on mine next year, to see if that changes anything.

 

[goeduck]

Never been a starter fluid person, I figure I might as well fix the real problem. Some brands can (in some carbs) really gunk up the gaskets.

 

[Ford850]

Choke makes the most sense to me. Maybe it’s adjusted ok but are you pulling the knob all the way up? Sometimes those pull knobs need lubed a little so the rod doesn’t bind.

 

[the old grind]

Throttle is ~ 1/2 or so open when cranking with choke on?

My Husky's 28hp B&S needs at least that much since new for 'cold' start, 5 yrs now.

My Terramite's 20hp Honda requires full choke and 3/4 or more throttle to start cold in any weather, .. choke to start warm too. (Says so on labels and in op manual.)

That one is still till running fine after 15yrs, bot 'used' off rental fleet.

Even with full choke if throttle is not open enough only idle system providing fuel to lean-burning SGEs.

Honda has shut-off solenoid in carb bowl and another on the 'firewall'. Nothing new to me and never a problem with either of them.

All my cans get Sta-Bil added when I bring 'em home. No diff ever noticed with 'off-season' gasoline.

 

[ray66v]

Throttle is ~ 1/2 or so open when cranking with choke on?

My Husky's 28hp B&S needs at least that much since new for 'cold' start, 5 yrs now.

On consumer grade equipment, they generally don't have a separate choke, and throttle anymore. It's usually just one lever with choke settings at full deflection.

This no doubt is part of the problem, since it limits your starting options.

Apparently, too many people were running them with the choke part of the way on, which makes a lot of pollution. That's also why the primer bulb has replaced the choke on many engines.

 

[the old grind]

Never saw a 'big twin' with a primer bulb. Single cyl < 6hp, yeah, and handhelds. Riding mower ain't chain saw.

btw, Only combined throttle/choke I have is on '96 Dixon 13hp B&S single. Separate choke lever on DR stumper and all others.

 

[ray66v]

Never saw a 'big twin' with a primer bulb. Single cyl < 6hp, yeah, and handhelds. Riding mower ain't chain saw.

I wasn't suggesting there was. That would be futile, since a large engine would require a workout.

I am told, they put plunger style primers on snowmobiles.

Being a pilot, I'm familiar with that style, because they use them on small aircraft. And, I like them. But, they can cause a fire, if used improperly. I would suspect that's why consumer grade mowers don't have them.

I'm thinking of making up a primer system with an electric fuel pump, operated by a push button.

 

[tomplum]

A few thoughts on small engines that tie in with this thread: 1)Repeated starting fluid use can actually be habit forming for engines. It is better to address the issues rather than rely on its use. Carburetor spray is a safer alternative and for intermittent use. 2) Your carburetor's throttle plate is wide open. Right now, no matter where the throttle is set- it is wide open when the engine is not running. If you can see the throttle arm or linkage, watch it try to close as you crank the engine and as the engine starts.3) Briggs Intek twins can normally require extended cranking when cold if they have sat for several weeks. Mostly it is simply the design of the intake manifold and the performance of the carburetor. For best results, stabilize your fuel and run every couple of weeks to cycle fresh fuel into the carb plus maintain the fuel level in the float bowl. If they (or really just about any OPE engine) have a cold starting issue every time- ensure the choke is closing, the fuel fresh, test for fuel pump output at first crank, feel for the click of the anti backfire solenoid at the bowl of the carb when the key is cycled. These four things seem to be the issue with the majority of cold start issues. Of course there are other factors which may require attention. 4) Many of the smaller engines that had primers were more forgiving than a like engine with a choke for cold starts. Many went to auto chokes, including the twins on your rider. A step forward?

 

[Industrial Toys]

Wouldn't Carburator spray be more like a gateway drug then?

I have almost never used Sarting fluid on any engine and never on a Diesel. I do use it for seating large tires though.

 

[ForumJunkie]

Thanks for the tips.

Tractor is at the shop, and is getting choke parts replaced under warranty.
I will try to ask them the specific issue.

My tractor has a manual choke and manual throttle lever.