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

These are the sounds issued forth from my beloved Tecumseh engines equipped with fixed Jets. I don't own one but my friend does on a machine I recomended and he constantly rags me about it. In an effort to get him off my back I have researched the following and these are the results:

1) The replacement carb for a medium frame Tecumseh is 632334A ( this is a part # that replaces a disontinued part but the blow up diagram of the replacement shows an adjustable main jet. Therefore I ASSUME it is adjustable.

2) The carburetor repair kit for this model is 632347 

I was able to secure a blowup diagram of this carb and the list of parts in the repair kit. It APPEARS all of the main jet parts are present in the kit.I NEED VERIFICATION If this includes the needle and the jet. 

If one were to remove the fixed jet from the current carb which I believe is the green plastic tube held in by O-rings and replace it with the adjustable jet and needle from the #632347 repair kit would it work? Could you retrofit the new bowl with the adjustable assembly or would you have to buy a new bowl?

If anybody could verify or correct my assumptions I would be most appreciative.

Marc

Just for the record -theHonda GX series engine on my power washer made the same spit, sputter,cough,blemph sounds due to it's fixed jet carb. Honda has addressed this problem by producing a line of altitude related jets. Another words if you want to richen up a Honda fixed jet carb parts are available. The carb will still be fixed jet but at a richer setting.

Richie,   You are quite right about actual horsepower in service being less than rated horsepower.  However, I believe all manufacturers test the same way in accordance with SAE J1940 (Small Engine Power and Torque Rating Procedure) so one should be able to compare motors fairly.  If anyone cheats on this they would expose themselves to a huge class action suit.    -Bob

Hi there Bob,

Yes, you are correct and thank you for bringing that important point up.  Still, I consider it a despicable advertising practice.  Using this LawnBoy ad to make my point, and why I'm making such a big deal about all of this, the consumer believes they are buying a 6.5 hp lawnmower and paying good money for it.  If you take the time to read the fine print, well, it's as you pointed out.  From this ad, it appears LawnBoy plays on both sides of the fence.  On one side they are telling you you're getting a very potent walk-behind mower, yet they are stating in the fine print it's a farce.  I don't recall seeing this disclaimer on any of my higher hp OPE with a Tecumseh engine on it.  LawnBoy has a slight conscience.

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MSRP: $339.00 - $459.00 Models: Model 10683 Model 10684 Model 10685 Model 10686 Compare All Models

• 6.5 hp Easy Start Tecumseh® Engine* • Push, Variable Speed, and Sens-a-Speed™ Self-Propel System • 21" Steel Deck • Compact Storage • Exclusive Features Designed to Fit You • Outstanding Ease of Use Features • 3-n-1 System • 2-Year Complete Coverage Warranty

* This engine was manufactured and laboratory rated by the Tecumseh Power Company at 6.5 gross horsepower in accordance with SAE J1940. As configured to meet safety, emission, and operating requirements, the actual horsepower on this class of lawn mower will be significantly lower.

Hi Richie

To quote you 

and why I'm making such a big deal about all of this, the consumer believes they are buying a (blankety blank)

I don't think you are making a big deal out of it at all. Your just investigating a complicated issue. 

Lot of stuff involved that is neither white or black.  It's gray.  Needs to be understood if your interested.  I think you would be quite surprised on the number of viewers following your issues.  Nice point on the Lawnboy post. 

I think you got lot of interest following along, and you will get counter points posted, lot of time they are just actually helping you get to the bottom of it,  (playing the devils advocate thing) I believe and I know you know the prev post on the testing standard was a devil's advocate help thing. 

Sure sometimes your gonna get some who may or may not know more on the subject,  or just are irritated and don't think it is important to get that deep into it.  They can voice their opinion, and then go out and buy a "Blankety Blank." because that is about how much they know about what they are actually buying.   Maybe close to nothing.

At least that's the way I'm lookin at it.

You go guy, don't have to knock yourself out, just stay steady, one piece at a time.

Appreciate your insight and investigation

Ben07

PS all the lawn boys from bout early 70's up to the newer 4 cycle (d-400, d-600, F series, Duraforce) were designed to work in the neighborhood 0f 2800 to 3100 rpm. When I say designed, I think they always tried to make their operating range close to the peak output,  (not 100 percent certain on the duraforce as never rebuilt one of them yet )  when they would exceed that they would say in their literature in the case of a three and 1/2 hp it would say 3.5+  (that plus thing started with the F series, and believe me it don't mean plus  a tenth of a hp,  they are strong running engines,  I'd bet they are closer to 5 )so if they take a 6.5 that has a rated  peak at say 3800 RPM then there would be less at the 3100,  which is exactly one of your points.  (and this is a little better area to make your point as there is no gearing involved, the blade speed is 1 for 1 with the rpm of the engine,  when your dealing with the Snow blower engines, the overall issue gets clouded by gearing involvement etc.  So it is easier for the manufacturer to do a spin on  what actually is happening.  Sorry if that's too deep for anyone.

Hi Guys-

Been mulling over the question of hp ratings for a few days as this thread has developed and wonder if we really want our engines turning at max hp (rpm) all the time. Certainly we don't use our auto engines at max hp when we are going 30mph.

If most of the time my blower will do a satisfactory job at 90% of it's rated hp. and then when I hit the EOD the governor kicks in and allows for the development of max hp I have no problem. Do we really want the wear associated with running at max hp. all the time?

The other issue of course is are we really being charged for something that is there anyway when we buy the higher hp. model of the same displacement?Auto engines of the same displacement with the same heads etc. have been rated at different hp. by changing the carb or ignition or "chip" or exhaust manifold or distributor as long as I can remember. You don't need me to explain to you it's a matter of marketing. But in a way we as consumers benefit.

I am looking to purchase a unit for my son and took a look at the Simplicity line. They offer two nice units built on the same 24 inch frame. One is a 9hp. and the other is a 10hp. The difference in MSRP is $200. I assume the two engines are the same displacement Briggs with different tuning . The more expensive unit offers as standard equiptment other features such as light, handwarmers etc. along with the "larger engine". My point is how much more would that unit cost if the engine was a completely different model? 

 The manufacturers I believe would limit the # of hp choices available because the cost of producing so many "different" models is not warranted by the size of the market . If they can't increase hp through tuning then we aren't going to have the number of choices we now enjoy. Would you want to have to choose between an 8hp and 13hp with nothing in the middle when you go to buy your next machine?

Someone PLEASE send some snow to Long Island,

Marc

mml4 wrote:

Hi Marc,

mml4 wrote:

Hi MM14..

A car is different because you vary the speed to the load or speed you choose,  If you want to Run ia at peakRPM, on a straight say a straight road you could do it all day. However if it had a governor on it, it would not let you..  I know you know peak does not mean Red Line.

However a governor will never let one of these machines run at peak if the governor setting is at a lower RPM than peak.  The governor only tries to keep the machine from slowing down (remember I said "Try" there for the slown process") when under a load.  It also keeps the machine from turning higher than the goverened RPM.  It never shoots for more RPM.  It dumps more gas into it, but it never tries to exceede the rpm.  If you manually excede the RPM  by forcing the throttle open It will do the same as the load condition, however in reverse it will lower the throttle back.

Analagy like driving on a 65 mph highway in 4th gear, standard trans.  you come to a hill, steep  going up the hill you got to floor the accelerator to try and maintain the speed. you do that however speed drops to 40  , now even if you are able to maintain 40 you are going to heat the motor up real fast.  You have an alternative, you can downshift , using the gearing advantage bring the car back up to 65, only difference is the motor is now running at a higher rpm , closer to peak etc. 

However with the governor setting you don't have the same choice, cause it only opens the accelerator to maintain an rpm.

In the same analagy as above now with a governor in the motor,  The same thing would have happened at first the car would have dropped speed to 40 mph.  so you do a quick down shift.  you will never get the car back up to 65 mph, cause it takes more RPM's than the goverened RPM. (so you will have this big powerfull engine crawling up a hill like it's a wimp, ) 

The whole point  here is, once you put a governor on it, you got to look at it differently.  there could now be anything under that hood of that car. A weak engine to a strong engine,.  A lot of it is how much they want to charge for it,  they make a one size fits all . get their manufacturing cost advantage there and then label the engine as the price will bear. 

This can all be summarized by saying there is a fudge factor involved in how these engines are related to power caused by the way they can and are required to rate their engines.  The manufacturer takes advantage of it to reduce their manufacturing costs.  And to get into the pockets with fatter wallets.  And to help the EPA gain controll, they go to the same country clubs.

Now the assasins are coming to my house as we speak.  That's ok they can pry it out of my cool dead hands to quote C. Heston.

So after all that has been discussed on this subject  How bout we get a feel for other's opinions  Make a quick post , in agreement or not.  It would be interesting

Ben07

I could care less myself. I can look at charts and graphs and know what  I need. Even in cars it's a pain, 200HP is one car is not going to provide the same thing as 200HP in another car, too many considerating factors to throw into the mix on what you'll end up with.

That's just my personal opinion.

Let me qualify that a little bit.

Yes, I would like to see engine manufacturers have the true HP ratings of the engines, advertised. What I don't really care about is a class action law suit, I have no need for that myself. As long as the spec's are published and easily found, I'm good to go.

Actually that is what some of us are saying you may be actually getting. less choices than actually implied by the seller

A choice between 8 and a 13. (over 50 percent in BHP between the two almost identical engine. however the rasting is at  a much higher operating rpm that the machine can't run at with a governor)  Big bucks in the differences, sure some more features, which does kind of camoflague and confuse the issue,  There is still a big free percent left over for the engine charge going back to the MFG for the low cost internal slight carb differences. 

also when you run them under load and rpm, drops to peak torque RPM  and you will find that there is no where close to a 50 plus percent increase in power between them there.  So do you actually have like five choices or do you only have in essence only like two?  

Ben07

Marshall wrote:

100 percent agreement  (relavent specs)