Snow Blower Performance

Industrial Toys · Feb 26, 2008

Hi People;

I have a big problem and quite a disappointment. Over the years, I noticed that not all snowblowers are created equal. The best blower I ever owned was a Lucknow 6.5 foot behind a Universal 445 tractor. Nothing I owned since, has worked as well.

Recently, I bought a 7 foot Mckee SnowLander, double Auger blower, that was equipped with a 65 HP Wisconsin Engine. I don't know if McKee made this machine, but i don't think so. The
engine has a Rockford clutch, that is then belt driven (4 belts) where it is reduced and then to a smaller double roller gear and then to the input shaft of the blower with a larger gear.

I use this on the front of a Kubota R510 using a skid steer attach plate.

The problem is that the performance is miserable, as far as throwing distance. The clearance of the impeller is quite close, within half an inch. I thought about changing gear ratios to make the blower run faster, but got into some heavy stuff, and think that maybe I don't have the horse power.

The engine starts like a dream (even though I detest gas engines) but wonder if the engine might be weak. It doesn't appear to burn oil, but could this be, that the engine isn't producing 65 HP?

Does anyone out there have any real experience as to what makes a snow blower perform well? Can one do anything to improve the performance? Being able to blow snow a good distance, is a real asset, when doing large areas. Right now, the blower only blows twenty five feet or so.

Maybe a nitrous kit?

Thanks

RFB · Feb 26, 2008

25 feet is not poor performance, although further is better.

What I have found is that there are several factors in play with snowblower performance. One of those is the water content of the snow; very wet heavy snow blows "chunkier" and not as far as dry powder, but powder is also more widely dispersed than wet snow, which seems more uniform in its deposit area.

The prime consideration in my experience has been fan (not auger) characteristics: size of fan blades and speed.

When fan speed drops off, fan velocity and distance seem to suffer in direct proportion. As long as I maintain fan speed by keeping the pto at rated (540) speed, performance remains good. As tractor/blower feed speed increases, one reaches a "sweet" spot that feeds enough snow at the proper rate that allows proper fan speed and tractor movement, and resultant optimum throw.

hdbikercouple · Feb 26, 2008

there was a post awhile ago and 1/2 was way too much . they were saying about a dimes thickness. hope it helps i'm no expert.

hdbikercouple · Feb 26, 2008

there was a post awhile ago and 1/2 was way too much . they were saying about a dimes thickness. hope it helps i'm no expert.

tessiers · Feb 26, 2008

My blower has about 3/16" between fan and housing. It blows even wet snow 50'+, if I keep the RPM's up

Industrial Toys · Feb 26, 2008

I wonder if it is worth the effort to rebuild the impeller? I looked at another non-achiever snow blower of mine, a George White "Blizzard" 7 foot single auger, to inspect the fan clearance, and was surprised to find that the fan housing gets rather far away from the fan already some distance before the snow exits, so it made me wonder, just how critical distance is.

When I run this blower, on my JD 6200, I have the engine opened up wide, turbo going, and little performance here too.

My GF has someone do her snow, and he shows up in a 2WD JD, with the engine just above idle, moving snow a great distance.

I've got to find out, what gives!

RFB · Feb 27, 2008

I don't know if it would help, but something like this Snowblower Impeller Kit might be an easy way to close the gap.

hwp · Feb 27, 2008

There are two factors which affect the performance of a snowblower - discharge velocity and clearance between the impeller and the drum. To a point, the greater the discharge velocity, the further the throw. A discharage velocity of about 5000 feet per minute should give at least a fifty foot throw. A 20 inch diameter impeller turning at 1000 rpm will give a discharge velocity of about 5200 fpm.

The gap between the impeller and the drum affects the ability of the impeller to carry the snow to the point of discharge. The drums on most snowblowers are not round but slightly oval. The critical sweep is from bottom dead centre to the point of discharge 90 degrees later - the rest doesn't matter. When the gap between the impeller and drum in this part of the rotation becomes too large, performance suffers considerably. I was told by the owner of the shop that built my snowblower that the impeller should pick up a dime at BDC and carry it to the point of discharge. I follow his advice and rebuild the tips on the impeller of my snowblower when the tips get worn to this point - about every second season. When I rebuild them I strive for a clearance of 0.020". The result is the machine is back to peak performance.

You questioned whether or not you engine had enough power to run the snowblower - i would think so. The rule of thumb I have always heard is 5hp per foot of throat - you are well beyond that.

I hope this helps.

Industrial Toys · Feb 27, 2008

Good information. I understood the part about the fan cavity not being
round but oval, however, on my George White, from bottom dead centre,
is where the oval starts and the clearance becomes huge! A few inches.
This is what had me baffled!

But I really don't care about that snow blower, as I will get rid of it.

It's the other, self powered one, I would like to optimize. I could add those filler plates, but I would question the fact that there might be drag caused by the uneven impeller surface. Short of building an entirely new impeller, what can one do to extend the impeller blades, while still keeping it balanced?