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Model #: 2691526 33" B&S Snapper Rear Engine Rider

The thing is less than a year old and has been running well, until now... It died suddenly while mowing with no prior signs of a struggle. The key start does jack, not even a click. The pull start will turn the engine and even start the engine but it will die after just a second or two. It's acting like it would if I tried to start it in gear. Like a safety switch is flipped or something. I have confirmed a spark. How can I confirm safety switch?

I don't have any small engine experience. What would be the likeliest culprit? Anyone mind helping me troubleshoot this?

Thank you.

Just to help you out on this and maybe other forums.

Post numbers of either the mower or engine. In this case you have an unknown running issue so we need both. Could be a switch (mower) or dirty carburetor (engine).

We don't need an entire mower history of where you got it and on what day....... How big the deck is most of the time.

Tell us what it is and isn't - doing like this.

1.engine doesn't run
2.starts but dies a few seconds later
3.I have spark
4.could be a safety switch, dirty carb or I forgot to open the vent on top of the fuel cap.

P.S.
making a video and posting to youtube or taking pictures help us a lot.

Test you seat switch with a VOM electrical meter. The switch should make/break connection as pressure is added/subtracted from the seat.

Do you wash this mower with water ??

How do you know you have spark? Neither a spark tester nor seeing a spark nor getting shocked guarantee that the spark is strong enough to fire under compression.

However, I don't think that's your problem. If the key start doesn't work (and the battery is hot!) it's probably a safety switch. Could possibly be the ignition switch.

slomo said:

Just to help you out on this and maybe other forums.

Post numbers of either the mower or engine. In this case you have an unknown running issue so we need both. Could be a switch (mower) or dirty carburetor (engine).

We don't need an entire mower history of where you got it and on what day....... How big the deck is most of the time.

Tell us what it is and isn't - doing like this.

1.engine doesn't run
2.starts but dies a few seconds later
3.I have spark
4.could be a safety switch, dirty carb or I forgot to open the vent on top of the fuel cap.

P.S.
making a video and posting to youtube or taking pictures help us a lot.

Click to expand...

Here are all the numbers I could find:
On the back of the mower below the motor: MODEL 2691526, REV 00, SERIAL NO. 4001502015
On the right side of the motor above the rear right wheel: MODEL 31R777, TYPE 0052 G1, CODE 200316ZD
On the engine cover: Serial #: 2003160516448, Model Number: 31R7770052G1
Also on the engine cover: Engine Family: LBSXS.5002VV, EU: e5*2016/1628SYB1/P*1050*00, ECS: EM 80087075

It is:
1. Showing spark at the end of the plug when turned with the pull start.
2. Starting, then stopping immediately when using the pull start.

It isn't:
3. Making a peep when the key is turned. Not even a click.
4. Running.

It was:
5. Running just fine like a brand new mower should with no signs of trouble prior to it stopping suddenly. No rocks or sticks were hit right before it stopped. I was driving in a straight line, on level ground, mowing San Augustine grass.

Born2Mow said:

Test you seat switch with a VOM electrical meter. The switch should make/break connection as pressure is added/subtracted from the seat.

Do you wash this mower with water ??

Click to expand...

How does the seat switch work? Does it ground to kill? Or does it close the circuit when depressed?

The reason I ask is because I took the switch out and tested it, and it appears to be a functioning switch, but I'm not certain. When the seat/switch is depressed (as if someone is sitting on the seat) the meter reads "overflow". But when the switch is NOT depressed (as if no one were on the seat) the meter reads a closed circuit with a steady .3-.4 ohms. This seems to be the opposite of what you suggested above. It appears to open the circuit when someone is seated. Is this the way it's supposed to be?

Richard Milhous said:

How do you know you have spark? Neither a spark tester nor seeing a spark nor getting shocked guarantee that the spark is strong enough to fire under compression.

However, I don't think that's your problem. If the key start doesn't work (and the battery is hot!) it's probably a safety switch. Could possibly be the ignition switch.

Click to expand...

I pulled the plug and and pulled the pull start and saw the spark on the engine block. The battery is good. I thought ignition switch too, but that wouldn't explain why it stopped mid-mow, would it? I'm starting to think it's the brake/clutch switch. Where is that?

Nm, I found the brake/clutch switch. How to I test this switch? It has 4 terminals.

Update:

1. Brake switch tested good with meter.
2. Seat switch tested good with meter.
3. Ignition switch tested good in all positions with meter.
4. With all switches physically depressed mower will still not start.
5. Confirmed battery is good by hooking up to a battery charger.

Update:

I was able to get the engine to fire with some starter fluid, but it quickly died again.

Visible spark is not proof of adequate spark. On two recent threads here, spark was detectible but turned out to be inadequate. But again, I doubt that's your problem.

Keyed ignition switches can be treacherous, especially if they control multiple circuits. More than once I have had a switch that functioned fine sometimes but could get into a not-quite-right position where one or more connections were wrong. Safety switches are more likely your culprit, but I wouldn't rule out the ignition switch yet.

Resolved:
The red wire from the ignition to the starter solenoid melted, or was somehow pinched and exposed the wire. I have no idea how the wire was damaged, but it happened between where it comes out of the central shaft and goes into the battery compartment. This is right by the motor. Has anyone seen this before? I really hope it wasn't critters chewing on my mower.

I just started following the electricity from the battery to the spark plug and got to the starter solenoid. I was going to remove/test the solenoid when I noticed the 10A bus fuse. I pulled it out, tested it, and sure enough it looked fine but tested bad. I replaced the fuse and while putting in the new fuse I noticed the damaged wire. I repaired the wire and tucked it up into the battery compartment and she started right up and runs fine now.

check the fuse

being it fires on starter fluid sounds to me like a fuel issue not a spark or electrical problem

Critters usually leave a residue of acorn husks, chewed insulation, feces, and whatnot. A strategically positioned block of rat poison is a good preventive. Replace twice a year.

If the breach was caused by friction/heat, you can protect the repaired wire by relocating it or wrapping it in electrical tape. But wrapping in tape does promote corrosion. I like to crimp or solder the joint and drown it in hot glue to forestall that. Glue also keeps the tape from falling off when it dries out, or a crimped joint from disconnecting. Silicone might work even better.

johnandchrisinmo said:

being it fires on starter fluid sounds to me like a fuel issue not a spark or electrical problem

Click to expand...

could be a valve issue

How many times do I need to encourage people not to use starting fluid. U Can blow a head gasket and or a head. Had guy to bust a head on a Generac engine with it. DO NOT USE STARTING FLUID TO TRY AND START AN ENGINE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Use something like Gum Out carb. cleaner works fine will not blow head gasket of heads.

2020snapperrer said:

How does the seat switch work? Does it ground to kill? Or does it close the circuit when depressed?

The reason I ask is because I took the switch out and tested it, and it appears to be a functioning switch, but I'm not certain. When the seat/switch is depressed (as if someone is sitting on the seat) the meter reads "overflow". But when the switch is NOT depressed (as if no one were on the seat) the meter reads a closed circuit with a steady .3-.4 ohms. This seems to be the opposite of what you suggested above. It appears to open the circuit when someone is seated. Is this the way it's supposed to be?

Click to expand...

Yes, switch is good.

When you get off the seat, that switch should be a short or close to 0 Ohms. That switch shorts the ignition coil out and prevents spark. When you sit down on the seat, switch should read OPEN.

2020snapperrer said:

Update:

I was able to get the engine to fire with some starter fluid, but it quickly died again.

Click to expand...

Carb or fuel delivery issue.

Dirty fuel tank, fuel line decomposing and a possible dirty fuel filter.

You gave it some spray fuel, engine consumed it and died. It wants more fuel to run.

Is the vent open on the gas cap? Mine is a little screw vent deal. Open it to mow. Close the vent to park the mower.

2020snapperrer said:

Resolved:
The red wire from the ignition to the starter solenoid melted, or was somehow pinched and exposed the wire. I have no idea how the wire was damaged, but it happened between where it comes out of the central shaft and goes into the battery compartment. This is right by the motor. Has anyone seen this before? I really hope it wasn't critters chewing on my mower.

I just started following the electricity from the battery to the spark plug and got to the starter solenoid. I was going to remove/test the solenoid when I noticed the 10A bus fuse. I pulled it out, tested it, and sure enough it looked fine but tested bad. I replaced the fuse and while putting in the new fuse I noticed the damaged wire. I repaired the wire and tucked it up into the battery compartment and she started right up and runs fine now.

Click to expand...

Wire looks smashed by something.

I would dress up those wires with plastic loom and some zip ties. Or electrical tape if you have some.

Or a piece of vacuum hose from a car. I've made more than one repair by chopping off a bit of vacuum hose from a run that had slack in it, or connected to some emission stuff that I really didn't care about.

Richard Milhous said:

Or a piece of vacuum hose from a car. I've made more than one repair by chopping off a bit of vacuum hose from a run that had slack in it, or connected to some emission stuff that I really didn't care about.

Click to expand...

Right, use something to bundle and protect the wires. Use grandma's yarn if you have to.

While U had the carb off did U check the fuel shut off solenoid. Turn the key on and listen for the solenoid to click. If not U can test it just plug it in with it screwed out of carb. turn the key on to see if the plunger retracts. If not most of the time U can clean it with carb cleaner. Spray it and work the plunger until it operates freely.

slomo said:

Yes, switch is good.

When you get off the seat, that switch should be a short or close to 0 Ohms. That switch shorts the ignition coil out and prevents spark. When you sit down on the seat, switch should read OPEN.

Click to expand...

Not all the time some seat switches activate a relay and in that case could read right the opposite. Which would kill the engine.