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.

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.

I find this entire thread very interesting. I have been wondering about the differences between the 9 and 11 bhp OHV Snow King engines, since they too appear to be identical. Does anyone know if the stuff discussed previously (particularly jetting) about the L-head engines applies to the OHV?

I wouldn't mind a little bit more more ooomph from my 926DLE.

John

Good info Richie, I figured it was probably jetting.

Ust to re-jet the Mikuni carbs on by bikes and my Merc outboards to gain HP, worked best with air intake and exhuast flow increased to match.

Richie wrote:
Yeah, that's what i've been doing but every now and again, i forget and the neighbors know it   I still think there are some mixture issues that linger, as if i let it idle for a while(more than 60 seconds or so) if i raise the throttle it falters, sputters, and if i raise too quick, it stalls.  If it just popped every now and again on throttle down i wouldn't be too concerned.  But with the sputter on throttle up, i def think it's a wee bit on the rich side, as the exhaust puff that result looks just like when its choked for too long.  I do think mines a bit on the fat side, but i'm also inclined to leave it cause when i load it down hard it's just got all kinds of oomph.  I first want to have a chunk of time to play with it where its cold, but not so cold my fingers go numb. we'll see.  Anybody know a place i can get my SB dyno'ed if i rejet ??? :)

This is very interesting.  Thank you Richie for posting this information, and taking the time to research this. 

  Richie,

    Based on your info, Toro is charging $100. 00 more for the 1028LXE over the 828LXE, just for a JET difference!!

Sounds like Toro is ripping off the public!!

Greater HP out of the same displacement, means shorter engine life!

                                                                   Fred