OHV/OHC vs. Flatheads.... AND THE WINNER IS......!

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Okay ladies and gentlemen, it's time for BITOG's first one time and final all out war between old fashioned Flathead fans against the newfangled hi-tec OHV/OHC fans! Good ol proven Briggs/Tecumseh flathead vs Honda OHC engines?! In the long run, which will prove to prevail? Which has the grunt needed for hard work everyone wishes they could pawn off on their kids instead of their hard-earned cash? Seriously though. The simple, proven reliable flathead engines, vs the newer OHC engines. I would say taht a 6.75 lb/ft Briggs and a 6.9lb/ft honda OHC have roughly the same power. But I know there are those that would argue. I won't deny that the OHV engines have lower emissions and lower fuel consumption.
 
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How many times can you run an OHC engine mower completely out of oil, seize it, allow it to cool, add oil, restart and keep on mowing? Maybe once if you are very lucky. Used to do it all the time with a beater B&S engine mower. But I do like the OHC smoothness and power.
 
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 Originally Posted By: Pablo
How many times can you run an OHC engine mower completely out of oil, seize it, allow it to cool, add oil, restart and keep on mowing? Maybe once if you are very lucky. Used to do it all the time with a beater B&S engine mower. But I do like the OHC smoothness and power.
So true. I can't count how many times I've run one out of oil (my father's on purpose when I was a kid), as the governor traveled toward full throttle just to add oil and getting some leverage to break it free by spinning the blade and have it run fine afterwards. Is that a run on sentence??
 

JTK

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 Originally Posted By: rudolphna
Okay ladies and gentlemen, it's time for BITOG's first one time and final all out war between old fashioned Flathead fans against the newfangled hi-tec OHV/OHC fans!
First and final? This has been talked about a bunch. For a push mower it makes little difference IMO. Like we say over and over, it's the overal construction of the mower that makes them last. The engine; Be it a side valve or OHV normally outlasts the deck it's bolted to. One whack against an un-mowable object and any engine is junk. Once you get to ~7hp and up is where OHV makes a difference IMO (like a snowblower, generator, power washer, etc..). They tend to be easier to start, have snappier throttle response and use less fuel. Joel
 
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 Originally Posted By: JTK
 Originally Posted By: rudolphna
Okay ladies and gentlemen, it's time for BITOG's first one time and final all out war between old fashioned Flathead fans against the newfangled hi-tec OHV/OHC fans!
First and final? This has been talked about a bunch. For a push mower it makes little difference IMO. Like we say over and over, it's the overal construction of the mower that makes them last. The engine; Be it a side valve or OHV normally outlasts the deck it's bolted to. One whack against an un-mowable object and any engine is junk. Once you get to ~7hp and up is where OHV makes a difference IMO (like a snowblower, generator, power washer, etc..). They tend to be easier to start, have snappier throttle response and use less fuel. Joel
OHV is definitely better on fuel.
 
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I agree with Lexus114 here. The advantage of the OHC engines is emissions and fuel economy. However, for something as utilitarian as a lawn mower I personally won't pay a premium for a OHC engine. Often times the Honda powered mowers are much more expensive than the B&S engine. It's simply hard to argue with the reliability of the B&S.
 
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Who'll be the first to produce a mower with 4-valves, DOHC and VVT? Might as well throw in throttle-by-wire and fuel injection. Variable vane turbo w/intercooler anyone? :)
 
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 Originally Posted By: ViragoBry
Who'll be the first to produce a mower with 4-valves, DOHC and VVT? Might as well throw in throttle-by-wire and fuel injection. Variable vane turbo w/intercooler anyone? :-)
And dont forget a Catalytic Converter!
 
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 Originally Posted By: FowVay
However, for something as utilitarian as a lawn mower I personally won't pay a premium for a OHC engine. Often times the Honda powered mowers are much more expensive than the B&S engine. It's simply hard to argue with the reliability of the B&S.
Ding ding! For a lawnmower you can't beat a cheap proven flathead. I believe that a flathead is much better for your average residential user that probably never checks or changes the oil. They just seem to stand up to abuse better.
 
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For a fairly low-priced mower ($240 to $300) you can't beat one with the Honda GCV 160 engine. Especially if you are not one to check the oil often. I have a Craftsman mower with this engine, purchased back in 2000. Paid $289 for it. I have an hour meter on it, and it has just passed 500 hours. It has a little over 50 hours on its last oil change, and it is still right on the full mark. I usually change it at about 60 hours or one year. It has never, since 2000, required any additional oil during a one year OCI. It has never been below the full mark. Sears had what was probably the latest model of this mower on sale this year. It was still $289. Some brands have this engine on their push mower selling for less than $250. I know that some higher priced mowers use this same engine and charge a premium price for those compared to what they charge for practically identical mowers with a Briggs & Stratton. Thats good for their bottomline: I'll bet they don't pay any more for their engines than, say, Craftsman or any of the other lower priced mowers.
 
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 Originally Posted By: Pablo
How many times can you run an OHC engine mower completely out of oil, seize it, allow it to cool, add oil, restart and keep on mowing? Maybe once if you are very lucky. Used to do it all the time with a beater B&S engine mower. But I do like the OHC smoothness and power.
Come on, Pablo - you know an oil man like you is not going to run any motor out of oil. As far as a Honda OHC engine is concerned, I don't know if you could ever run one out of oil if you just checked it once every two or three years. My GCV 160 has never been an eighth of an inch below the full mark in the last nine years. Of course, I change oil every year, at about the 60 hour mark. I used M1 5W30 while my old stock of SL lasted, and now I have changed to M1 High Mileage, which is still SL. One year, about 5 years ago, I used M1 0W30, and still didn't use any. Maybe I should, one of these years, not change the oil and just see if it would start to use oil in a couple of years.
 
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OHV/OHC engines are really great and probably the first advance in small engine design since the 1960's. Long over-due.
 
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I don't quite follow the logic of someone arguing that flathead is better because they're cheaper when the ignorant or moronic people neglect their gear. I don't get how the valve train technology has any bearing on whether the piston comes unstuck from the bore after seizing from running out of oil. Flatheads aren't better, they are just cheaper and more disposable. Just what we need, more disposable goods. You'll pay more for an OHV/OHC unit and maybe, just maybe, that might cause owners to take a little better care. OHV/OHC are more efficient (more power from less displacement), more fuel efficient and quieter than flatheads. I have a 24 year old L-head 8HP SnowKing, Honda GXV140 (OHV commercial series) and Honda GC160 OHC.
 
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 Originally Posted By: lexus114
 Originally Posted By: ViragoBry
Who'll be the first to produce a mower with 4-valves, DOHC and VVT? Might as well throw in throttle-by-wire and fuel injection. Variable vane turbo w/intercooler anyone? :-)
And dont forget a Catalytic Converter!
Actually they are mandated for 2011, we have some with cats in-stock at work. They started making last year. Here's a link. http://www.canadiantire.ca/AST/browse/2/...2BLawnmower.jsp
 
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 Originally Posted By: Maritime Storm
 Originally Posted By: lexus114
 Originally Posted By: ViragoBry
Who'll be the first to produce a mower with 4-valves, DOHC and VVT? Might as well throw in throttle-by-wire and fuel injection. Variable vane turbo w/intercooler anyone? :-)
And dont forget a Catalytic Converter!
Actually they are mandated for 2011, we have some with cats in-stock at work. They started making last year. Here's a link. http://www.canadiantire.ca/AST/browse/2/...2BLawnmower.jsp
Oh you`ve got to be friggin kidding me!! whats next,one on our rear ends??
 
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I couldn't get over how great our Craftsman 17.5 B&S OHV does on fuel. Our old early 90's Craftsman 12HP drink it like it was sweet tea on a hot day. Now it barely sips on it and feels like it has twice the output. Unfortunately, the engine is the only good thing about this 2004/2005 mower. The deck is [censored]... starter... I hate this new stuff. I'd like to have this engine on an older body.
 
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 Originally Posted By: Maritime Storm
Actually they are mandated for 2011, we have some with cats in-stock at work. They started making last year. Here's a link. http://www.canadiantire.ca/AST/browse/2/...2BLawnmower.jsp
Yes, but they put it on one of those chinese "top quality" engine. Guess how long that cat will last? Once plugged or no longer effective, it will probably pollute the same, or more than a Honda or B&S. For that price, you can get a name brand with a better (and reliable) engine...
 
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