LM21SW starting issues

MarcC

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I have had my Ariens LM21SW repaired every summer for the past 2-3 summers for the same problem.
The mower will run just fine until I stop to remove the bag and then it will not restart. My repair man says
it is the ignition module and has replaced it 2-3 times. I just got it back from him the other day, started
mowing and as soon as I shut it off, it would not restart. Anyone have any suggestions? Could it be
something other than the module?
Thanks in advance.
 

mechanic mark

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see page 25, why do you shut engine down to empty bag?
When you click on above website, enter your model & serial numbers, you will have Service, Parts, Operators Manuals. Make sure you clean underside of deck often with carburetor topside, skyward.
 
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upupandaway

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it would help if u post an engine model number. this model was made for about 30years so it was sold with many engines. It sounds like you have a carb problem more than an ignition problem.
Does your mower have a rubber primer on top of the engine?(my LM21 does) If so press that 2 x and try to start it.
If not, go to the store and get a spray can of starter fluid. (assuming they did not give u a lemon of ignition coil) When it won't start, remove the air filter and spray in some starter fluid and try to start it and if it runs fine until u stop it again.
Post what you find.
 

bertsmobile1

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Some mowers have a cut off switch on the catcher
If yours has one that is where I would be looking first
 

MarcC

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Here are a couple of photos of my mower. It will not stay running when I remove the bag unless I can somehow hold the handle and dump the clippings.

Ariens mower (1).jpgAriens mower (2).jpg
 

upupandaway

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Well.....call me lazy but when shredding\bagging leaves, i got tired of having to restart it, I tied a rope to hold the safety bar for me while i dumped the leaves. Of course i stop the mower if i need to walk away and do whatever...

Get a string and with the safety bar engaged(before u start the motor) tie a loop that can hold the bar for you and keep it running while you trouble shoot. Make sure the loop is big enough you can move it to either side to disengage and stop the engine.

This would be your quick fix to it not restarting if you don't want to start troubleshooting which would mean taking some stuff apart.
 

upupandaway

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I use a velcro strap for that on my Lawn Boy.
Good idea! I have a box of the velcro which has a loop on one end(so i can't drop it) in the server room. I'l grab one of those...

MarcC: From what you say your problem is, one likely cause is that the bolt holding the carb float bowl has small passages. Dirt\deposits are restricting the flow of fuel. Take that bolt and with one of these- tip cleaner to clean out especially the vertical passage.
 
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