Bolens 425 cultivator wont stay running - Bolens 25cc 2-Cycle Gas Cultivator BL425

Bolens BL410 21BK410G163 Tiller Parts
Try that out

you may want to try and see if your cylinder walls are scratched when it loses compression try using som oil in the cylinder and see if the compression comes back up. if so then you may have a scratch cylinder. if compression does not come up then look at the valves to see if they are seating right. if not then you may have to do a valve job.

should be some sort of tensioner device or spring that would need to be slacked off in order to facilitate removal try that

I would make sure that you have the proper gas/oil ratio mixed first. If that is ok then I would have the filter changed. If that doesn't solve the problem then you should take it in to have the carburetor serviced.

How old is it? Does it show a spark when you remove plug an hold against engine while pulling cord? Did you replace plug? It is the most common problem. Remove the stop wire an try to start, if it does or you see spark the switch is bad. I would check put these things before replacing module.

I have the exact same problem, new carb, new coil, new gas. I think it is not building enough compression to support combustion.
Won't even pop starting fluid !!

clean the screen inside the muffler

Spray starter fluid in the air filter. This should work.

Definitely stay away from Ryobi, Troy Bilt, Bolens and Yard Machines by MTD. They are all Ryobi with different brand names on them. (goes for trimmers too) MTD owns them all. The best small tiller, IMHO, is Mantis. (2-cycle) I think Sears sells them now. I have one and it will run circles around the rest.