I dont think that it's a compression problem as you said it ran fine. If you have a compression problem it will start and run until the engine reaches it's operating temp then it will either die or start to loose a lot of power and seem very sluggish. It will have problems starting when hot and will idle horribly, and you didnt say anything about any of this. You said it runs fine for one week then stops running for a week, and then runs fine for another week, it sounds more like a tuning issue then anything.

From week to week the ambient temps can change drastically, humidity ambient temp along with a whole other host of things will cause a tunning issue if they change a lot. Also the way you said it started up for 5 seconds then shut off sounds like a tuning issue that can be resolved without buying a new piston/sleeve or a whole new engine. As if it is a tuning issue then you will end up having the same problem with that motor as every engine needs to be tuned, so buying a new enigne wont help things if this is whats the problem.


Also I would stay away from the blue wire and just use the glow ignitor that you bought. It saves your ez-starts battery and makes the glow plug much warmer then that blue wire is going to make it, making starting a little bit easier. You can try another glow plug and see if thats the problem but I doubt that it is the problem, because of what you have said about it running fine for a week then not running.

As I said before it sounds like a tuning issue to me.