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

Recently I installed a tach/hour meter on my Toro 828 LXE and found theat the maximum operating governed engine speed was 3,300 RPM spiking to 3,330 RPM's.  I actually felt it was running a bit slowly but decided to use it, as is,  immediately after it stopped snowing on Sunday.  Well, we had about a foot of snow on the driveway with some 18" drifts, and the EOD was about 21", thanks to the snow plows.  The machine handled it perfectly until I got to the  EOD.  While blowing through it, the Tecumseh engine wanted to stall.  Nobody can tell me this is normal on a high end snowblower like this.  It was 15 degrees and it was freshly plowed loose snow.  If it had been wet, I would have been able to look past it.

With all the research I've done in the last 24 hours, I am nearly convinced that the governed RPM set by the manufacurer may have much to do with the horse power rating they give them.  The Tecumseh 9hp-11hp Snowking engines all vary greatly in governed RPM, as low as 3,350 up to 3,700 on the 11hp OHV version.  When I see that the Tecumseh 9hp is 318cc's and the 11hp is also 318cc's, where are they getting these horse power ratings from. Making an engine OHV gives you that much more power?

Well, I wasn't able to find the governed operating RPM for my Tec 8hp L-head engine, and given the wide margin of RPM's on their engines, I decided to raise the operating speed of mine to what I felt it should be.  Initially I raised it to 3,600 as it was suggested to me to do, but I felt this was too fast by the way it sounded.  So I then reduced it to 3,400 spiking to 3,430.  Roughly 80-100 RPM's higher than what it was. 

The result of this, I took it out into the street to the 28" high, five foot across snow drifts left on the side of the street from the snowplows.  These drifts are 8" higher than my auger housing.  The sun was out and the snow was nice and moist, perfect for making snowballs.  I raised the throttle to operating RPM, put it in 1st gear and off I sent it into the drift.  The chute started to toss the snow some 40 feet across the road and you could now hear the engine under a load.  The difference this time is that the engine was maintained speed and not a hint of it wanting to stall.  In fact, the tires actually broke loose and I started pushing it into the drift to the point it began tunneling.  The entire time the engine didn't faulter for a second and I actually felt I had a 10 hp engine on this great machine.

What a difference a very small increase in governed engine RPM makes.  At one point on Sunday I was upset with myself for not shelling out the extra money for Toro's top of the line 11 hp OHV version for over $1,600.00.  Well, after how this experiment worked out, now I feel I just saved myself over $400.00 because this snowblower can go through anything now.

Richie,

       thanks for all your long work in research.                                             18 degrees

Wow, there had to be something more to it.  Thanks Richie for your love of research and information on this topic.  It's just great. 

You are all very welcome, thank you.

Del

Several engine builders have what they call eng families they are the same bore and stroke valves and pistons, BUT they do change the camshaft. Different cam grind can give eng more compression/HP. This I know for a fact in my Kohler K301 -12hp I put in the Kohler 18hp OHV cam nothing else other than gaskets/seal...WOW what a difference! Can do any job now in higher gear, burns little more gas but job is faster.  So if the hp is higher and the rest is the same check the camshaft most of the time its a low cost upgrade.

KohlerTech wrote:
I'll bite, how about starting a new discussion about advertised HP.

Hi Guys!

The obvious-Every engine has a spec#.Regardless of the stickers if the spec #'s are the same the engine is the same.

Not sure about Tecumseh but if you remember the Briggs -Simplicity situation last spring we confirmed that the 9 through12 HP Briggs were the exact same engine. We also found that several of the engines in that run did not appear in the Briggs catalog of engines. The phantom models were produced for Simplicity by Briggs on special order and were simply re:stickered. If anyone missed that discussion search for the thread "Converation with Simplicity".

Marc  

The Intek Snow engines brochure shows the same net horsepower and net torque curves for the 9 and 11 hp models.

Net hp is a max of 6 for the 6.5 & 7.5; about 9 for the 9 & 11 at 3600rpm; and about 9.8 for the 13 at 3600.

Net torque is max 9 ft lbs for the 6.5&7.5; a little over 13 for the 9&11; and 16 for the 13.

I've only ever found one reference to torque for Tecumseh snow engines, and it is a graphic that is not readable.....

Thanks for starting a great thread, and thanks for everyones input. I found this to be veddddddyyyyy interesting.

Fyi....copy of post regarding discussion I had with Tecumseh past November on power specifics of the 9.25 and 11Hp motors.