Sounds like the Main Jet in the carb is clogged.
Also make sure fuel shut off valve is open.

Full model numbers are useful such as HRM215K2SXA etc. That way I can post an exploded diagram of the "correct" carb.

How do I find the model #? The engine serial # GJAB-6575668 and the # on the deck by the grass catcher is MZBB-6127454?

The main jet huh hmmm I think I must tell you it runs perfectly while its running and then it needs to sit for a few minutes before I can start it again and it will again run for 30 seconds.

If I can equate it to starting a boat witht he safety lanyard detached, the engine will start perfectly then shut right down. Not sure that helped but that is exactly what it does?

I suspected a bad coil or the switch that is controlled by the blade release mechanism that allows the coil to fire.

Shall I just rebuild the carb and or how shall I correct the main jet issue?

Funny I can build an entire race card and make it hum but a simple two stroke has me baffled :)

"Suddenly when I try to start it it will run for about 5 seconds then immediately shut down"

"The main jet huh hmmm I think I must tell you it runs perfectly while its running and then it needs to sit for a few minutes before I can start it again and it will again run for 30 seconds."

5 seconds and 30 seconds IS a big diffeence when it comes to carbs.

Sounds like the fuel flow is restricted to the carb.
There us supposed to be an inline filter that's part of the tank outlet.

IF this carb has the drain plug, remove it and see what kind of fuel flow you gave to the carb.

Isn't there more than just Harmony 215 on the shroud?
My Masters says HR215SXA.
What's it say on the owners manual?

'but a simple two stroke has me baffled'

It's a 4-cycle with overhead cam and overhead valves.

Good point it is a 4 stroke isn't it, sometimes I miss the merely obvious.

No nothing else on the shroud just Harmony 215.

Owners manual was lost two moves ago :(

Wow I need to watch what I type as I can see how subtle things will make a huge difference in diagnosis.

The motor will start the first time and run for say 1-5 seconds then shutdown as if the ignition was turned off. Then if you immediately try to restart it it will not start. If you wait a minute or two then it will start again repeating the cycle.

Can't help you with your problem, but you can find your owners manual here:

Here is a link that might be useful: Honda manuals

thats a fuel delivery problem.........

I have a Honda Harmony 215 Lawn Mower. It has been popping, spitting and sputtering, and then will go back to running smooth for awhile. It even died a couple of times, but started right back up. It has the ORIGINAL spark plug in it! I went and bought a new plug, but I don't know what to set the gap at. Could you tell me what to set the gap at? Also, any other suggestions as to the cause of this issue?

Thank You!

John

Check the gas tank cap. There is a small hole in the top. This could be blocked and causing a vacuum in the tank stopping the flow of gas. sometimes its the simple things that are hard to find :-)

i've got a similar problem, but i've narrowed it down to water in the fuel.

took off the carburator and drained it(had fuel and water up in there), then tried running it with starting fluid.

Thing ran on starter fluid but would die as if it didn't have any gasoline.

But i've got gasoline coming to the carburator.

Think the carburator filter could be clogged?

Perhaps the fuel line is clogged w/ crud from the gas can. Is this the first time you've started it this year? Not sure if that model has a gas filter, but if it does that would be the first thing to check.