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.

How about it T-Man? Inquiring minds want to know!

Marc

Just reviewed Emmos' chart and found three different crankshaft service #'s. I assume this could account for differences in HP for engines of the same displacement. . This could mean the weight of the rotating mass in the engines are different and could also effect HP.

Marc

Richie wrote:
Yes Ritchie, You are right. No messing with stuff we shouldn't.

But where exactly is that screw? I don't need to adjust it much. Just until it throws further than Ross's machine. You know the guy across the street with the Porcshe.


Do you think a Tec L head can hold 15 pounds of boost?

Or how about just a little taste of nitrous when it's nice and sunny on the weekend and everyone is outside brushing off the cars?

Hey Rob,

Now you're talking I have no problem helping you break a rich guys chops  Remember, I felt my Toro was running slower than it should and I also have the tach/hour meter installed as a guide.  But, if you must experiment; just inside where the red throttle lever is, about a 1/4"-1/2" inside that slot the lever rides in, you'll see a very little silver allen head screw.  I turned it about one turn clockwise or less.  One important thing, you have to have a very good flashlight pointed in there when doing this.  Even with the light, its actually hard to tell it is even turning.  Keep your eyes sharp while doing it.  I'd hate to have you come back on the board and tell us you made the adjustment and the engine turned at 4,000 RPM's   I also did this while it was running at max RPM so I could hear what was going on in addition to cheching the RPM meter.

"Here's the confusing part, the link Emmo was kind enough to dig out for me shows ALL 9hp models, yet Toro says this is a 8hp engine.  So I have a DE-rated 9hp??  Is Toro calling a 9hp an 8hp for EPA reasons??? "

Richie,

I know what you're saying and geeze, it's a nightmere to try have the answers! Want to see a big offender? Look at Sears Lawnmowers that run a 7HP Briggs, explain that one one to me. Rob hit on the reason for it, it's marketing and being the most powerful kid on the block. 

But you know, as long as the snow blows far enough and the grass gets cut nicely without tremendous bog downs when doing either, what the heck do I care what they label it as long as I didn't over pay for something I didn't get?

Marshall,

I just realized that exact thing just before going to bed, exactly what you posted.  What made me realize this was because we were trying to find engine specifications for a Tecumseh 8hp l-head engine, but couldn't.   Why can't any of us find it, because it doesn't exist.  A Toro 828 LXE is actually a 9hp L-head, the model engine number proved it.  So anyone that has purchase this snowblower, you can feel a bit happier you have a larger engine that you didn't even know you received, but due to an industry wide marketing ploy, you paid for it somewhere along the line.  As you pointed out, Marshall, this is obviously an industry wide thing and certainly some type of marketing ploy is at the bottom of it.  I hope I'm not jumping the gun here, but it seems that because I felt my engine was running a bit slower at operating RPM, this ordeal seems to have uncovered one of this industries dirty little secrets, I think.  I also fully agree with you, as long as the machine does what is expected, I have no problem with it.  Lets see what tomorrow brings.  Thanks again, Marshall.   

Hi folks,

Excellent Richie... !


Glad you got some definitive answers...

...and thanks for shring 'em here...


Dave...

  Richie,

        Do you have have to change the Jet or do you change the carb assmbly??

If, the jet, I assume it has to be the high speed one. Am I correct ?

                                                                                             Fred  

Wow, so with a jet swap I could have an ariens 1024 instead of an 824 :)  That's amazing.  Remember back in the day when cylinder bore actually affected HP?  Now it almost seems like (for the HMSK line anyway) that "one bore fits all"(ok, most)  It's a great discovery, Richie, but nothing I think i 'll take advantage of, or maybe i will.  I get an occaisional back fire on throttle down, so when i'm "in there" tweaking it out, i just might swap, if i can get the parts.  we'll see

Hi Fred,

As the tech explained to me, jetting does it all.  He didn't say the carb assembly has to be replaced, strictly jetting.  In fact, I did specifically ask about the 10hp engines having the same 318cc's and what makes it a 10hp as opposed to an 8 or 9.  Is it a different crank or muffler and such that Tecumseh uses; he was very insistant about it being jetting.  As for exactly what type of jet or the jet size, one must look in a service manual or find the exploded views of a specific engine.  That will tell you the jetting you need.  Re-jetting actually is pretty easy.  I used to do it on my twin cylinder, twin carb Skidoo 500cc snowmobile.  Jetting was crucial on those recreational machines because you really wanted to match the carb jetting to the altitude were going to be playing in.  Hope this helps a bit.  Maybe someone can locate the service manuals for us so we can order some jetting, assuming some want to play

Terrapin, try not to chop the throttle down so quickly.  Easing the engine down from operating RPM will stop it from backfiring.  If you do make a jetting change, please let use know.  Thanks.