2 Stroke vs 4 Stroke

Now this one is pretty simple.  While power and efficiency can be argued, and realistically here the 4 cycle would win out in the end, there are other advantages to the 4 cycle, particularly in terms of a snow thrower. 

First off, here's how the 2 work:

2 STROKE - Ignites fuel every rise and fall of piston

A 2 cycle engine fires every single time the piston rises and a 4 cycle fires every other time the piston rises.  That right there is a big difference in not only fuel economy but also in the most important of all, wear and tear on the engine itself.  And while some argue that a 2 cycle has a far more powerful output, the reality is that the power gains are not significant enough or even more importantly, are not necessary enough to justify purchasing an engine that will just wear out on you in no time. 

4 STROKE - Ignites fuel every other rise and fall of piston

Now here's the truth of it:  A 2 cycle is dirty and self fouling.  It must be lubricated by oil added to the fuel in exacting mixtures, and this overall lack of complete and proper lubrication make it very poor and short lived in a wet environment.  Now on the other hand a 4 cycle is fully self-lubricated by it's own oil reservoir, keeping the engine fully oiled and clean, thus having a much longer life, not only just under a heavy workload, but particularly for where a snow thrower operates, in probably the most terrible and wet conditions possible.

And while for a summertime dry conditions chainsaw, a very small and very powerful engine which is the 2 stroke, is a great or even ideal option, this is NOT the case with a snow thrower, particularly if you're going to be putting over $300-$500 into your machine in order to purchase a real monster that will really get that job done right.  Purchasing a new machine every year or two is a bit much.  And for most people, the easy task of simply fueling up the beast and checking oil is enough.  Mixing fuel and keeping that specialized mix on hand can become quite a chore, particularly in a heavy winter.  And as I said, the water will just add to the fouling overall that the 2 stroke already suffers from immensely.  One way or another, you're going to be replacing that 2 stroke eventually.  How well you baby the machine by keeping it indoors in ideal dry conditions between uses will be what decides when that time comes.  Whereas the 4 stroke with it's fully lubricated system and exceptionally low level of fouling within the engine will last essentially indefinitely if taken care of properly as well.  In fact, you can even leave the 4 stroke just in the open garage door between runs or even on the porch in between and it will still last just fine.  The 2 strokes life will be shortened greatly by such treatment for sure.  And I'll give it to you this way:  In terms of power, when I've used the same model snow thrower, one with 2 stroke and one with 4, there was only a very small difference in power.  Oh, but it was noticeable!  But was it an amazing difference?  No.  So for me, looking at the overall, I choose a 4 stroke any day over a 2 stroke - for a snow thrower, a car, etc.  Any larger engine or machine.  Now for hand held devices, chainsaws and the like, well then I would go with the 2 stroke...  But that's just me right?  You have the info now, so you decide.  But in terms of no hassle and excellent self care and preservation (and well more than enough power to get the job done), it's the 4 stroke hands down for a snow thrower.