LawnMachines 300e Mower won't start-- Choke?

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Hey y'all, recently picked up a new lawn mower from a friend that did not start. It is a Lawn Machines 300E Briggs and Stratton mower. I thought it would be an easy fix, but I am stumped. I checked the spark plug and it seems fine. Not sure what to try next. I thought it might be the choke being stuck open but that ended up not being the case.

If you have an ideas let me know.
 
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Scrubcadet10

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That's not the choke, that is the throttle shaft, governor link and governor arm, which is connected to the governor inside the engine. and when the engine is off it sits at wide open.. it maintains the engine speed and applies throttle when the engine is in heavy grass and needs more fuel.

You should have a primer bulb on the air filter cover you took off. a big red one.
 
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That's not the choke, that is the throttle shaft, governor link and governor arm, which is connected to the governor inside the engine. and when the engine is off it sits at wide open.. it maintains the engine speed and applies throttle when the engine is in heavy grass and needs more fuel.

You should have a primer bulb on the air filter cover you took off. a big red one.
Well now everyone knows that I know next to nothing about these things. What other things should I try to figure out what is wrong with my mower?
 

Scrubcadet10

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well first lets see if it has spark.
If you have an carburetor cleaner (that is NOT non-flammable) and/ or starting fluid, or even a bit of gasoline, sprayed right into the carb for about a 2 second burst should be enough for it fire up, so spray a starting fluid into the carb, try to start, if it runs then dies, fuel delivery issue, either the carb still needs cleaned or the gas is bad/ water contaminated.
however this one is a choke version, not primer type.

now if it doesn't start at all, i would be looking for spark...remove the top engine cover (3 10mm screws) you'll see the ignition coil, and a small black wire going to the back of the engine, unplug that wire, it is the Kill wire.
try to start with that wire unplugged, repeat the earlier steps, and if it starts with the wire unplugged, there is an issue with the kill/brake assembly at the back of the engine or the wire insulation is rubbed off and shorting to ground (mower)
if it still doesn't start with the wire unplugged, bad coil.

** however i wouldn't mess with over sizing that jet
 
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well first lets see if it has spark.
If you have an carburetor cleaner (that is NOT non-flammable) and/ or starting fluid, or even a bit of gasoline, sprayed right into the carb for about a 2 second burst should be enough for it fire up, so spray a starting fluid into the carb, try to start, if it runs then dies, fuel delivery issue, either the carb still needs cleaned or the gas is bad/ water contaminated.
however this one is a choke version, not primer type.

now if it doesn't start at all, i would be looking for spark...remove the top engine cover (3 10mm screws) you'll see the ignition coil, and a small black wire going to the back of the engine, unplug that wire, it is the Kill wire.
try to start with that wire unplugged, repeat the earlier steps, and if it starts with the wire unplugged, there is an issue with the kill/brake assembly at the back of the engine or the wire insulation is rubbed off and shorting to ground (mower)
if it still doesn't start with the wire unplugged, bad coil.

** however i wouldn't mess with over sizing that jet
Alright Ill give it a shot. Thank you
 

slomo

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How about some engine numbers?

Easy spark check. Stick you finger into the spark plug boot. Pull the rope. Report back here if you have spark. Just kidding.

What exactly did you check on the plug and how did you do it? Did you Ohm it out with a meter? If so should be 4-6K Ohms from boot to center conductor. Assuming you have a resistor plug that is.

Is the carb getting fuel TO the inlet pipe from tank? Fuel tank full of grass slash dirt slash grit and grime?

Like Scrubcadet10 said, spray something flammable into the carb. Pull the rope. See if it fires off for a few seconds. Report back here with your findings.

slomo
 

Born2Mow

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  1. The place to start with any engine you don't know the full history and age is all new fuel.
  2. Then the traditional: fuel, fire, and compression.
 
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How about some engine numbers?

Easy spark check. Stick you finger into the spark plug boot. Pull the rope. Report back here if you have spark. Just kidding.

What exactly did you check on the plug and how did you do it? Did you Ohm it out with a meter? If so should be 4-6K Ohms from boot to center conductor. Assuming you have a resistor plug that is.

Is the carb getting fuel TO the inlet pipe from tank? Fuel tank full of grass slash dirt slash grit and grime?

Like Scrubcadet10 said, spray something flammable into the carb. Pull the rope. See if it fires off for a few seconds. Report back here with your findings.

slomo
I just checked the spark plug. It is not a resistor plug, its an E3.20. It had a resistance of over 100k ohms which is not right hah. Ill blow some air through the gas tank to see if that's the issue. I don't have the equipment to test the spark plug so I pulled it out and checked to see if it was corroded or anything. It looks pretty new so unless its an internal thing, it seems okay.
the engine is a 08P5020055F1
serial: 17 0427 54 29274

Ill spray something into the carb.
 

slomo

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On the plug, 100K Ohms is bad. Unless you are touching carbon with the probes giving you that high reading. Get an NGK or Champion plug for your engine. Waiting on the flammable spray test.

slomo
 
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On the plug, 100K Ohms is bad. Unless you are touching carbon with the probes giving you that high reading. Get an NGK or Champion plug for your engine. Waiting on the flammable spray test.

slomo
The spark plug was pretty clean so it must just be a bad spark plug. I'm going to re-assemble it now and do the spray test.
 
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