Honda EU10i smoking. To ring or not to re-ring. That is the question.

whether tis nobler in the mind… blah de blah

Often the first symptom people actually notice is that machine cuts out after a few seconds running due to low oil level actuating the oil alert switch. If your Honda EU10i is smoky the first thing to do is run it for 20 or 30 minutes under a 900w load just in case the smoke is due to carbon build up in the exhaust muffler. If it is down to carbon then the engine will continue smoking until the carbon is burned off. If the smoke clears after a minute or so of running then the cause will be wear in the cylinder bore and piston rings rather than just carbon.

So what to do with a smoky Honda EU10i? The short and most practical answer is nothing. With most generators the engine has a cast iron sleeve in the cylinder which is very hard-wearing and as a result when the engine starts to burn oil one can just fit a new set of piston rings and all will be well. The EU10i has no liner so there will be as much wear on the cylinder bore as there is on the rings. A new cylinder bore costs around £120 plus VAT, the piston rings cost around £9 plus VAT and there are another £20 worth of bits and pieces that will need replacing as a matter of form. The whole job takes at least 4 hours. So unless you want to spend at least 4 hours and £150 plus VAT on sorting out your smoky EU10i then it’s probably not worth doing.

You can just change the rings and the problem will be improved for a while but it won’t be long before you are back where you started.  The best approach with an EU10i is to run  it with a very light (400:1) mix of 2 stroke oil from day 1 to improve the upper cylinder lubrication.

Curiously it has come to my attention that machines that have been run very hard at near capacity, fair much better than ones used under normal circumstances with a variety of loads. I recently dealt with a customer whose EU10i had done in excess of 3000 hours used only for running 3 x 250w halogen lights. The machine was showing very little signs of wear and appeared to be using no oil. I suspect the lack of carbon build up in a hard run engine is the source of such longevity.