This is “planting week”, where I put the veggie plants into the ground, shoot ’em with some Miracle Gro, and wait a few months for some real tomatoes, peppers, etc.  So, what happens in the middle of all this?  I burn out the engine in my Honda mini-tiller.

I had power-thatched the front lawn a few weeks ago, and the dead grass had been sucked into the motor housing, gotten packed around the aluminum cooling fins cutting off ventilation, and caused the little engine to overheat.  Pretty sad, since this is only about five years old and has light usage.  Still, I knew there was some grass in the housing, but wasn’t prepared for what looked like a bird’s nest of dead grass falling out when I took the engine apart.  Not only had the plastic housing melted in a few spots, the “head cover” also got deformed a bit from the heat.

Over at the Hobby Talk forums, I posted the symptoms, and it seems that I may have anything from damaged valves or valve seats, to a scored piston and cylinder wall.  The engine still starts, but the light ticking/tapping inside the engine starts making some noise just before it quits; my guess is it may be sticky valves.  (Valve stuck, loss of compression, engine stalls.)

In other words, it needs some serious repairs.  Or I need to replace it with another engine.  I’ve eyeballed a replacement on eBay, or the other option is to purchase a new Honda GX35 to replace it with, as it supercedes the GX31.

Fortunately, my lawn edger is also a Honda, and uses the exact same engine.  The only difference is that the gas tank and motor housing are oriented for vertical, not horizontal use.  Fearing the worst, I decided to borrow the engine from the edger.  I needn’t have worried: by removing two of the bolts on the recoil starter, and removing four more bolts, the edger handle/shaft came right off.  And on the tiller, that engine came off the tiller with only four bolts.   The transplant went rather quickly.  Aside from the gas tank being oriented the wrong way, the edger’s engine worked great on the tiller!

I don’t have to worry about the orientation on this engine.  The Honda mini 4-stroke engines are really quite amazing.  The little thing is very lightweight–you can hold it in the palm of your hand.  The design is very simple, yet durable.  The clutch on the bottom fits into a mating cup on the tiller or the edger–that’s why it was so easy to transplant.  And you can lay this engine in virtually any position, while running, as it has an oil mist lubrication system that works continuously at any angle.  That is why it can be used in portable hand-held applications like an edger or string trimmer, or mounted horizontally on the tiller with nothing more than a change in the gas tank to make filling easier.

And all it takes is one Bozo to not notice all the grass packed into the housing, and overheating it…