Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

FrankMA wrote:
You got good deal there jrtrebor , I too just bought a Powerlite just to play around with.  I got the 2 stroke bug from reading about boratifying Tecumseh engines.  It's been quite boring without snow so I thought to stimulate the economy a bit by picking up a used snowblower on CL.

Like FrankMA said, these things are like potato chips.  I'm on the lookout for a Toro CR20 or a Murray 21" SS with a Tecumseh HSK850 engine.   

Thanks for all your comments.  I was thrilled to get it for that price.  Bought it sight unseen, but figured I could part it out and make a little if it was beyond repairing.
You never know till you see it in person.  Got it all cleaned up and back together today, started on the first pull.  Now I've got four, 2-CCR2000  1-CCR2450  1-CR20E
Going to keep the CR20E and the CCR2450.  I want to put a chute crank system on the 2450 instead of the arm turn system.  Got everything I need off an old 2000
crank rod, gear box and rod bracket.  But I'm missing the chute ring gear, which is actually the bottom portion of the chute.

trouts2 - "Do you have any comments on how the SS's do so well with such low impeller speeds compared to the big guys?   I'm surprised they can toss as well as they do running such low impeller speeds".

I'm going to assume your really talking about auger tip/edge velocity speeds, Yes?
If so, then I would say that although they are slower I think they are pretty in line with the distance they throw snow.  Compared to a larger 2 stage. Also, obviously the distance a SS throws is very dependent on the type of snow they are throwing.  Much more so than a 2 stage.
RPM is everything when it comes to throwing distance.  A drop in engine RPM of just 100 or 200 can make a noticeable difference in the distance.  On my big blower, I once
calculated that for every drop of a 100 engine RPM he impeller tips slowed down somewhere around 320 rpm. 
Another factor in how far a blower throws, that has a lot of variables.  Is how much snow the blower is being fed.  Up to a point, the more snow you feed it the further it throws (dry snow goes further than wet).  If you don't feed it enough it's throw is pretty dismal. If you feed it too much the throw drops off but the volume through put may increase.  Up to a point, RPM again.

Borat's video was good in that it showed different RPMs being used on similar sized housings and HP.  In watching the video I was also thinking about the two different auger designs.
The conventional type in the Craftsmans and the Power Curve in the Toro.
SS blowers process snow very quickly, in and out.  I think that is part of the key to their abilities.
If snowblowers were horses
SS would be Thoroughbreds, and 2 stages would be Draft horses

Nicely done.  You going to bend the governor tab or just run it at stock rpms?

You'd be surprised by how much more performance you can get even by jacking the rpm up to 4500.  I actually had to slow my 221 down to 4000/4100  rpm because it was pulling me down the driveway too fast.  If you've got a level driveway, the added rpm will extend the throwing distance substantially and the increase in engine speed isn't enough to cause any concern.  The R-tek is a pretty durable engine.  With the split connecting rod, I wouldn't trust it to be spun too high for too long but I wouldn't be afraid to run it up to 5000 rpm on occasion.   

If you get some snow, let us know how you like it.  

Nice work, jrtrebor! I like the handles. Was it an eBay auction, with a local seller?

borat, what's split about the R-Tek's connecting rod vs, say, the HSK850's? In the HSK600, at least, the connecting rod is solid at the piston end, and bolts around the crankshaft at the other end. Though I just looked at the HSK850 exploded view (in "Predator Maco shark waiting for boratification.") and I see the 850's conrod is slipped over the crankshaft (as well as the wrist pin in the piston), and does not bolt together at either end. I'm guessing that's what you mean. Which means the smaller 600 is also of the split conrod design, I suppose. Hmmm. I wonder if the 600 will be less tolerant of revs. At least its piston is lighter.

High performance two cycle engines generally have solid conrods  and built up (pressed together)  cranks.  Built up cranks can take a fair amount of power but are not as strong as a solid piece.  Accordingly, when someone wants to ensure their super-modified or racing two cycle engines remain reliable under extreme loads, they weld the pieces of the crank together. 
 
Tecumseh has cleverly designed the HSK 8xx engines to have both solid conrod and crank.  That's a plus.  The fewer opportunities for rotating, reciprocating and other moving parts to loosen up, the more reliable/solid the engine will be. 

I wouldn't be too concerned about the HSK600 engine not being able to take a few hundred more rpm provided it was properly assembled.  Don't forget that just about every four cycle engine has split big end conrods and those engines can take some serious revs.  The only caveat is that if the engine's connecting rod and crank were not properly assembled (correct torque and lock washers), things could come apart in a hurry.  The bolts/nuts that hold the two pieces of the connecting rod together usually have a large flat washer that is to be bent up beside the nut or bolt to keep it the bolt from backing out.  If this critical step is overlooked, bad things can and will eventually happen. 

Chances are your engine hasn't been apart.  Accordingly, if it hasn't let go yet, chances are it won't.