Export thread

I have an MTD Yard Machines rear-tine tiller, model #21AA40M1000. Here is a link to the manual:
https://www.tillersdirect.com/manuals/21AA40M1000.pdf

I haven’t used it in a few years, as the garden didn’t need it, but now I have to fix part of my lawn. I’ve tried to start it up, but couldn’t get it going. I dumped the gas, added fresh, made sure the oil level was OK, and cleaned out the air filter. I pull the cord but nothing happens. I don’t know much about engines, so here are my questions.

What should I troubleshoot first? I was thinking of getting a new spark plug, but couldn’t figure out if there are different types or sizes. I didn’t see any specifications in the manual. Also not sure how to adjust clearance, and I don’t have a spark plug wrench, but willing to get whatever I need.

Anything else that would be a good place to start? The manual mentions the carburetor, but just says to see dealer. Is there something I should do with that? Not even sure where that is, since it doesn’t seem to be on any of the diagrams.

Feel free to dumb everything down. Like I said, I don’t do much on engines besides changing oil on my tractor mower.

Thanks so much!

I think your carburetor is probably gummed up after sitting that long. Take a look at Mustie1's video's. He goes into detail about carburetor cleaning.
https://www.youtube.com/watch?v=nAk_WDt3AD8

KenS said:

I think your carburetor is probably gummed up after sitting that long. Take a look at Mustie1's video's. He goes into detail about carburetor cleaning.
https://www.youtube.com/watch?v=nAk_WDt3AD8

Click to expand...

Thanks, I'll start there! Anything that I need to avoid doing to not kill things? Never worked on one before...

Hello,

Most probably carburetor as Kens' said.

But before going too far or buying too much stuff, you should remove the spark plug and check it for spark.
While in you can check state and gap (0.7mm == 0.025in). If it spark, no need for a new one and no electric problem.

Then you can dump some drops of fuel in the cylinder, screw the park plug and pull the rope. If it start than die, you have to clean / rebuild the carb (assuming fuel is coming to it).

Best advice I can give to you is to take a phone snapshot of everything at every step of the way. Makes reassembly much easier.

dfbroxy said:

Best advice I can give to you is to take a phone snapshot of everything at every step of the way. Makes reassembly much easier.

Click to expand...

When I kicked off I eventually dragged out the big camera.
It got put on a stand, over the mower or at the assembly bench and as digital photos cost nothing the shutter button took a lot of hits.
So may I was seriously considering a pro grade camera with a remote shutter button.

But it did save me lots of time, particularly with stuff where parts took months to come in so you forget or mix it up with the 20 others you have done in the mean time.

Sounds like a dirty carb. Hope you get it running soon!

Mkala said:

Hello,

Most probably carburetor as Kens' said.

But before going too far or buying too much stuff, you should remove the spark plug and check it for spark.
While in you can check state and gap (0.7mm == 0.025in). If it spark, no need for a new one and no electric problem.

Then you can dump some drops of fuel in the cylinder, screw the park plug and pull the rope. If it start than die, you have to clean / rebuild the carb (assuming fuel is coming to it).

Click to expand...

I'll start with that since it sounds simpler. This may sound dumb, but how do I test the spark plugs when I have it opened up? Just pull the cord and that makes a spark? Thanks!

Mkala said:

Hello,

Most probably carburetor as Kens' said.

But before going too far or buying too much stuff, you should remove the spark plug and check it for spark.
While in you can check state and gap (0.7mm == 0.025in). If it spark, no need for a new one and no electric problem.

Then you can dump some drops of fuel in the cylinder, screw the park plug and pull the rope. If it start than die, you have to clean / rebuild the carb (assuming fuel is coming to it).

Click to expand...

dfbroxy said:

Best advice I can give to you is to take a phone snapshot of everything at every step of the way. Makes reassembly much easier.

Click to expand...

I've definitely learned this before. Too many times of "I'm sure I'll remember what that is..."

bcemail said:

I'll start with that since it sounds simpler. This may sound dumb, but how do I test the spark plugs when I have it opened up? Just pull the cord and that makes a spark? Thanks!

Click to expand...

No dumb question, we can always learn The metal on spark plug has to touch metal of the engine, to allow grounding. Do not touch it or you will be zapped !
You have to put the throttle to run, as on stop it kill the ignition (or perhaps you have a switch). Then pull the rope normally, as you would start (easy with no plug in -> no compression)