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

I believe the HS621 was sold last sold in the US a few years ago.  Now it is only available in Canada.  I can't find this model new anywhere in the US.  The available current model is a HS520 which is smaller and have an overhead cam engine versus the superior OHV engine on the HS621?  The build quality also seemed to be cheapened on the HS520 as well.

On a different topic but somewhat related to Honda, I'm trying to understand why the model line up for the US market is so watered down compared what is available in Canada?  Canadian two stage models have even have hydraulic assist auger height adjustment, electric chute, as well as onboard 12V battery starter.  I know I am a minority when it comes to having these gizmos on a snowblower so bear with me.  If any of you have seen what is available from Yamaha in Japan, some folks may conclude that snowblowers available in the US are very primitive in comparison.   Does the US market not demand these features and technology?

In what way is the OHV engine superior to the OHC engine?  Are you talking  GX series vs. GC series or is the technology you're questioning?

borat wrote:
I may be incorrect in saying one is more superior than the other.  However, I do notice that the GX series engines are put on larger snowblowers.

An OHC engine is always OHV as well, but an OHV is not always an OHC engine. An OHV engine that’s not OHC uses pushrods and rocker arms to link the cam to the valves, but an OHC can link to the valves directly, but many also use rocker arms, forked if it’s a 4 valve per cylinder design. Certainly in high performance (high RPM) applications the OHC design is superior to the cam in body OHV design. The OHC engine has less reciprocating weight in the valve train, and thus, can control the valves more accurately at high RPM. In power equipment where engines typically operate at 3600 RPM, the advantage of an OHC design is minimal. It might be more of a marketing advantage than anything tangible.

MacLorry27 wrote:

That pretty much sums it up.  Personally, I prefer OHC engines.  That is single overhead cam not dual overhead cam.   I have a couple 500cc SOHC Suzuki engine ATVs and one 650cc DOHC Kawasaki motorcycle engine.  All three are singles.  I can adjust the valves on both Suzuki engines in less than one quarter of the time to do the one DOHC engine.  To adjust a DOHC engine valves, there is a considerable amount of tear down required to lift the cam off of the valves to replace shims.  SOHC engines have a valve adjustment access port that can be easily opened for quick valve adjustment.   When I was young, DOHC ruled.  They are the ultimate in cam performance configuration.  Now that I do my own work, ease of maintenance is where it's at.    

Now for a plus in favour of push rod engines.  In almost every case, a push rod engine will make more torque than an OHC engine of the same size.  Not completely sure but, I've read that it has something to do with the cam lobe shape.  Something with the push rod set up allowing for different cam shape than an OHC can use thus different torque characteristics.  The OHC engine will however make more horsepower but that will come at higher rpms which is of no significance with engines maxed out at 3600 rpm.  Another advantage of push rod engines is that the cylinder/head arrangement is more compact.  Often an in or two shorter than an equivalent displacement OHC engine. 

Did I say I liked OHC engines more that push rod engines?  Let me rephrase that.  I prefer over head cams in engines required to run at higher rpms.  In OPE applications, I'll take a push rod engine as readily as an OHC  engine.   Now, if it's a Honda GX overhead cam engine vs. a GC push rod engine I'm going for a GX every time regardless of valve configuration. 

Do you think the 621 was too close in size to their two stage models? I have a 520 honda and it does a nice job, I have never seen a 621. The 724 two stage that they sell is a 6.5 hp. I believe? Maybe they can sell the 520 for less money to make it more affordable for the guy that wants a honda?

Coldfingers

Coldfingers wrote:

I don't think the HS621 is too close in size to a HS724.  The HS724 is a step up in a different league, (2 stage, 6.5 hp, 24" path, self propelled, available in a track drive, and quite a bit more $$$).  However, I think the HS621 and HS724 may share the the same GX160 engine, just tuned differently.

I don't doubt that the HS520 does a decent job.  It's like a Toyota Camry or Chevy Malibu.  It does what most people want at prices people like.  However, the models from Toro and others with a 4 stroke engine do just as well too at the same price points. 

The ohc Honda ope engines are not as robust as the ohv GX series. They are basicly throw aways as the cost of repair is prohibitive. I'm surprised to hear of them on snow equiptment. Another example of price point being #1.

Marc  

mml4 wrote:

In some cases, you might be right.  However, the Honda GC series are the aluminum bore engines and less robust than the GX series.  If you buy a GX series OHC engine, it's as rugged as any other GX engine regardless of valve configuration.  I have a Honda GX series OHC  V-twin engine in my yard tractor.  The distinction is not whether it's OHC.  It whether it's a GX or a GC.  By the way, the B&S snow engines are all aluminum bore engines similar to the GC series.  Would they be considered as throw away also?

Borat

1)Check the SEW web site-Many Briggs Snow engines have a cast Iron bore.

2)I am sure the GX ohc engines are fine but the GC engines used on mowers and pressure washers have proven to be less than stellar having to do with the valve train.

 3)I didn't mention anything about Aluminum Bores being the basis for  throw aways on Hondas or Briggs or anything else so I am confused by your question.

However I do know that the special order Briggs used by Simplicity and Snapper on their blowers in 2005 were all aluminum bore engines badged as 9.5hp-12hp. They are fine units (my son has one in a Simplicity 1060DLXE) but you couldn't buy one from the  Briggs catalog. I am not sure about the later units as I haven't kept up.Perhaps you can enlighten us-

Marc

Tmml4 wrote:

!)  I said the B&S Snow engines have an aluminum bore.  I didn't mention any other B&S engines, of which, I'm fairly familiar with.  As far as I know, all of their Snow engines are aluminum bore.  They make a Snow Intek engine with a cast iron bore, but that's not the same as their Snow or Snow Max engines which are offered on all snow throwers using B&S overhead valve engines.  I've yet to see a Snow Intek on any available snow thrower presently on the market.  That's what  I'm referring to.   You can correct me if  I'm  wrong. 

2) I made the distinction that the GX engine regardless of valve configuration is superior to the GC series engines.  I'm not defending GC engines.  You had previously stated that the Honda OHC engines were inferior.

3) Aluminum bore is one of the major differences  (if not THE major difference) between a GC and a GX engine.   Considering the B&S snow series engines are aluminum bore as well, would they be classed as a throw away engine as you say the Honda GC is?