# learning about choking a gas engine



## nancy237 (May 29, 2008)

I have so much to learn to handle things on my own. If I understood these gas engines like my John Deer, gas trimmer, chainsaw, generator it would help me alot. I am learning about the fuel mixtures needed.

I thought the choke was something I would turn on until it starts, but a friend told me today it needs to be off and then slowly open after it starts..???


One thing I have surely learned is that guys never say if they don't know. I have been told lots of wrong & different things about some issues..The one that tells me one day they have no idea about something will have my respect.


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## gone-a-milkin (Mar 4, 2007)

Here is what I know, and I am not a mechanic. 

The choke reduces the amount of air that goes into the carburator. 
With less air, there is more fuel. When you are starting a 'cold' engine you need more fuel and less air, for it to get going and warmed up.
Then, as the engine warms up, you can let off the choke and it will continue to run.

My experience has been that if you let off the choke too soon, the engine may sputter and die, or it may just cough and still run.
I usually do it gradually, while I LISTEN to the engine. 
It will generally run really fast and then when you let off the choke, it slows down some. You dont want it to cough or sputter, just run smooth. 
If it gets choppy sounding, the engine is not warm enough yet. 

It takes practice to get a feel for when to let up on the choke. It takes a lot longer in cold weather.


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## Rick (May 10, 2002)

When starting a cold engine, engage the choke to reduce the air going through the carb. Unless it is brutally cold, you can generally disengage it right away to warm up the engine. 

FWIW We bought an Ariens Tiller and they recommend pulling the starter cord handle slowly and returning the handle to its original position when resistance is felt. This is to prevent moist air from intruding into the combustion chamber.


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## nancy237 (May 29, 2008)

Thanks...


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## JuliaAnn (Dec 7, 2004)

On one of our old 1960's pickups, I have to choke it when starting on most days unless it's really hot outside. Engage the choke, let it run for a minute, then ease it off. Same thing with our tiller.


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## farmerj (Aug 20, 2011)

Rick said:


> FWIW We bought an Ariens Tiller and they recommend pulling the starter cord handle slowly and returning the handle to its original position when resistance is felt. This is to prevent moist air from intruding into the combustion chamber.


Wha?:huh:


All you are doing is pulling the engine over to the compression stroke by doing that.

Makes it a little easier to start if you have a well tuned engine.

Once that sucker fires off, you are pulling in whatever ambient air you got. Moisture or not.

In the summer, you might be able to get by with a half choke position instead of a full choke. It might be that you have to feather the choke as well as it starts up being ready to flip it off entirely.


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## Zephaniah (Mar 16, 2010)

MAybe the misunderstanding is the term on and off. Open and closed might be better

When the choke is open all the air flows normal as when needed when warm.
When the choke is closed less air flows and the gas mixture is now "rich" [with gas] as needed when cold.

There should be little diagrams on the choke handle or near it that look like open and closed like this

||| Open

|\| Closed

|-| This cold be closed also


L


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## Guest (Aug 26, 2011)

Each gas engine has it's own little quirkes to get it started. You have to learn those quirkes. Generally, for a cold engine, you turn on the gas (if it has a shut off valve), close the choke completly, pump the primer 4 or 5 times (if it has one), and pull the starter until it starts. As it warms up you can slowly open the choke. Listen to the engine and if it starts to run rough while you are opening the choke, close it a bit and wait for it to warm up some more. When it is completly warm you should be able to open the choke all the way. For a warm engine you can leave the choke open and just pull the starter.

My lawn mower has no choke. You pump the primer about 12 times and it starts on the 3'd pull. My chain saw has no primer. You close the choke, pull the starter cord about 15 times until it sputters, open the choke and it starts on the next pull. On the snowblower you close the choke, pump the primer 3 times, and it starts on the third pull. The weed eater is about the same as the snowblower. So you see each of my pieces of equipment has it's own little sequence you have to go through to get it started.

When you store the motor for the off season, put Stabil in the last tank of gas and run the engine long enough to get the Stabil laced gas into the carburator. This will keep the gas from coating the inside of the carb with varnish. If a few years worth of varnish build up in the carb it will block passages and cause a sticking valve in the carb and it won't run. Most "broken" small engines just need their carbs cleaned. There are guys who make their living fixing small engine type tools and selling them on CL.


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## HermitJohn (May 10, 2002)

And just to add further complexity, there are those engines that have both the plastic pimple primer (PPP) and a partially disabled choke, where choke plate has a significant hole drilled in it.

My solution on those is to use epoxy putty and block the drilled hole in the choke plate, then use the choke like one would a traditional choke and forget about using the plastic pimple.


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## Macybaby (Jun 16, 2006)

Over the years we've had so many engines with manual chokes. the colder it is out, the more they are needed. In all cases, the choke needed to be closed before the engine was turned over. For some, you have to open it rather quickly once the engine starts, and others you had to leave it closed for several minutes.

And some times on really difficult to start days (well below zero) You might have to open the choke up fully, stick the pedal flat to the floor and crack it for several seconds until it tried to pop. Then you closed the choke off and cranked it and soon as it started, you had to be opening up the choke just a bit, and if it roared, you opened it more, and if it sputtered, you closed it. Was real fun doing that with a manual truck - one foot on the brake, one on the clutch, one hand on the key, one had on the manual choke.

I was sure happy with DH put a new 4 barrel carburetor on that truck! Still had a manual choke but it wasn't near as temperamental. 

Several of our small engines have fuel shutoff valves, and we shut the fuel and let it about run out of gas (or what is left in the line drips out). So when we go to start, closing the choke helps pull the fuel back into the lines. The two lawn mowers are that way, but both are electric start. I can't get either of my rototillers(pull start) to start without closing the choke, but it needs to be opened almost immediately upon starting or the engine will flood out and die.

At least most of my equipment has open/closed designations, and not on/off so I don't get confused which one is open.


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## Micheal (Jan 28, 2009)

To add to all the confusion - it may also depend on how "new" what you are trying to start is - some of these new-fangled engines have an "automatic" choke and you can't get to them without an odd-ball screwdriver and a masters degree in engine repair.........


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## MichaelK! (Oct 22, 2010)

Just follow the manufacturer's guidelines. There's no single check-all when using a broad range of different engines. For an older model car with a manual choke, pushing it in gradually may be appropriate.

On my late model generator, it won't start at all unless the choke is all the way closed, but runs best if I release all the choke a moment after it starts.

You just have to treat each engine as an individual and leave it at that.


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## Hooligan (Jul 18, 2007)

To further add to the confusion many engines have "enricheners" rather than chokes. You would not know the difference if you didn't know the difference. They are actuated in the same way. The difference is a choke limits the air to richen the mixture while an enrichener leaves the air alone but adds more fuel to the mixture.

General rule of thumb is to only use the choke/enrichener for just as long as it takes to get it to start. Once started back off the choke/enrichener and use the throttle to maintain a high idle until the engine warms enough to idle on it's own. Over use of the choke/enrichener can foul your plugs. Some engines are more forgiving than others.


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## salmonslayer (Jan 4, 2009)

Mostly all good advice and it really does depend on the idiosyncrasies of each engine but to the OP, your friend is mostly wrong. Generally you choke a cold engine before you start it and then ease off as it warms.

To give a few examples, our 4 wheeler (250 Suzuki) needs no choke during weather above about 50 but needs full choke below that and it is extremely temperamental about it. On cold days we fully choke it and it starts and after about 3 or 4 minutes we can ease off the choke and its good to go. When its below zero it doesnt like to start at all.

Our garden tractor (26 HP Kawasaki) needs a little choke to start regardless of the weather and then once its started you can ease the choke off almost immediately 

The Mrs old Sear garden mule (10 hp Tecumseh) never needs choke.

Our weedeaters, push lawn mowers, the log splitter, trash pump etc have the pimple primer and I never have trouble starting them regardless of the temp, 

Our 1948 Allis Chalmers WC Tractor has to have full choke to start regardless of temp and it takes 4 or 5 minutes to warm up before you can ease off the choke

All of our chainsaws need to be choked before they will start regardless of temp but once they are warm they dont need any choke. 

So basically, it depends on your temp, the type of engine, and even then you can have two identical engines that react differently (I have a buddy that cant start his 250cc 4 wheeler without full choke) and also you need to back off the choke as soon as you can.

Now your probably really confused!!


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## TNHermit (Jul 14, 2005)

Micheal said:


> To add to all the confusion - it may also depend on how "new" what you are trying to start is - some of these new-fangled engines have an "automatic" choke and you can't get to them without an odd-ball screwdriver and a masters degree in engine repair.........


Your right
My pressure washer has a nothing carb with NO adjustments, A throttle thing of some kind GRRRR and a bulb to pump gas in. I have found the bulb is the choke. I have to push mine till I get some resistance then a couple more times.

I just love govt regulation. If anybosy knows where you can buy an alternate REAL carb let me know or it seems it would be a good start up business.


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## HermitJohn (May 10, 2002)

I hate the plastic pimple primers. I suspect with some tinkering you could make a slide type choke out of sheetmetal simular to whats on many chainsaws to add to the end of a carb without a choke. You probably arent going to make a good butterfly type choke, at least not easily. And unless you can find a carb off an old piece of equipment, you arent going to find any modern carb that has the screw to adjust main jet. The main jet adjustment disappeared first, then the idle adjustment, then the choke itself. And many of the modern carbs just arent meant to be opened and rebuilt, only replaced as a whole unit. And on mowers most modern carbs are intended to run full governed speed all the time without being able to adjust throttle. The horrible thing will be when they figure how to economically put computer controlled fuel injection on your push lawn mower. Mowers are already throwaway, with some complex expensive fuel system they will be even more so.

As to the automatic choke on lawn mower, the Briggs I used to have on my Yazoo had one of those. Talk about annoying plus it used plastic pieces that didnt hold up and werent replaceable separately. With bit of Gorilla glue, bit of baling wire, and piece cut off an old radiator hose, I converted it to a manual choke that worked quite well. Sometimes so called progress is actually regress....


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## HermitJohn (May 10, 2002)

TNHermit said:


> it would be a good start up business.


It would be illegal to sell alternative unapproved adjustable parts for an EPA approved fuel system. You would have to make it as a replacement part for a pre-EPA designed engine and only sell it for that application. If somebody just happened to adapt it to their existing EPA approved engine on their own initiative, well thats between them and the EPA.... So far we dont have small engine inspections in this country so be unlikely any private individual would get in trouble doing this.


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## TNHermit (Jul 14, 2005)

HermitJohn said:


> It would be illegal to sell alternative unapproved adjustable parts for an EPA approved fuel system. You would have to make it as a replacement part for a pre-EPA designed engine and only sell it for that application. If somebody just happened to adapt it to their existing EPA approved engine on their own initiative, well thats between them and the EPA.... So far we dont have small engine inspections in this country so be unlikely any private individual would get in trouble doing this.


Stuff like that you don't sell. You take donations for your work  ANd ya just keep an old piece of junk engine around just in case so you can say you were gonna put it there and just thought yo u would try it. Between what we got now and the old down draft carbs ain't a lot out there.


As far as inspections dont tell that to Gibson guitar, The goat herders and a few others I can reference. And don't forget they soon want to look at your garden.


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## arabian knight (Dec 19, 2005)

HermitJohn said:


> I hate the plastic pimple primers. .


 Wow cause as far as I am concerned that was the BEST thing to happen on small engines in years and years.
Made weed eaters start easier, made chain saws start so much easier, Made Snowblowers start in cold weather very easy.
Can't see what a person would dislike in those primer bulbs. I see none what so ever.


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## Silvercreek Farmer (Oct 13, 2005)

Many 2 strokes seem to like full choke until the "pop" (give the slightest hint of wanting to start) then 1/2 choke until they start, 30 seconds or so at 1/2-3/4 throttle, until they warm up a little, then take the choke completely off. The only time I have trouble is if I only run one for a minute or so and then turn it off. Seems like they don't like to start back up very well...


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## HermitJohn (May 10, 2002)

arabian knight said:


> Wow cause as far as I am concerned that was the BEST thing to happen on small engines in years and years.
> Made weed eaters start easier, made chain saws start so much easier, Made Snowblowers start in cold weather very easy.
> Can't see what a person would dislike in those primer bulbs. I see none what so ever.


Manual choke is fully controllable. The plastic pimples are arbitrary, sometimes you punch 3 times, sometimes you punch 30 times. You have no idea how much gas is going in and it seems to vary time to time. Then when engine starts, it may die and you start over punching your little plastic pimple again and again. 

On other hand if you know how to use a choke and from what I can tell, you may even be old enough to remember manual chokes on automobiles, you simply close choke, start and slowly open it depending on how the engine sounds.

Modern small engine carbs are also set at factory to run very lean for pollution reasons. The ability to have control over a choke allows users to over ride such lean setting merely by leaving the choke partially closed. You can mow with manual choke partially closed. EPA wants to usurp this control. You cant mow your lawn while at same time punching the pimple to keep air fuel mix richer. Engines running full governed speed also pollute less thus elimination of ability to control engine speed. And engines can run leaner at higher rpm. So far only on lawn mowers but expect to see such on other equipment eventually.

With a properly functioning carburetor and a properly functioning human brain operating it, a choke will start an engine far quicker than the plastic pimples. As others have said, it takes bit experience with a particular engine and carburetor how to make manual choke most effective.

But if you like plastic pimple fuel systems, for sure you live in best of times to experience them. Punch that pimple! Over and over and over again until you are happy. Or you can buy a can of ether and drill small cheater hole in air filter canister that the plastic straw on aerosol can fits in and give it a shot to start engine. Sure there is a way to automate this process. I remember some older diesel tractors without glow plugs where they had an automated starting fluid setup. You just replaced the can fluid every once in a while. Hey it kept one from having to open air cleaner every time like on some old diesels. Or again you can drill a cheater hole that aerosol straw will fit into.


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## OkieDavid (Jan 15, 2007)

It's a guy thing.... Each of us takes great pride in being the only member of the family that can start a piece of equipment. It was through many colorful language sessions that we learned you must turn around clockwise two and a half revolutions, alternate from your left foot to your right foot and pull the cord (all done while making sure the centerline of the pulley is in alignment with Capricorn.....


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## Hooligan (Jul 18, 2007)

HermitJohn said:


> Modern small engine carbs are also set at factory to run very lean for pollution reasons. The ability to have control over a choke allows users to over ride such lean setting merely by leaving the choke partially closed. You can mow with manual choke partially closed. EPA wants to usurp this control. You cant mow your lawn while at same time punching the pimple to keep air fuel mix richer. Engines running full governed speed also pollute less thus elimination of ability to control engine speed. And engines can run leaner at higher rpm. So far only on lawn mowers but expect to see such on other equipment eventually.
> 
> .


Why would you want to vary the engine speed on a piece of equipment designed to perform its best at a specific rpm? Every engine that I have that is designed to be operate at various rpms has a choke/enrichener. Some of them have the primer bulb also and some don't. My 12 year old push mower has no choke/enrichener and starts every time after a few pushes on the primer bulb. It has a throttle if I need to adjust the motor speed but the governed speed at WOT seems right and works well. If you have to richen the mixture to get it to run right then there is a problem somewhere that you are masking.

I think the "pimple" is more of a primer bulb to get fuel to the carb before the vacuum takes over rather than a choke mechanism.

Like and outboard motor has. Both my outboards have enricheners and primer bulbs and I need to use both to cold start either of them.


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## arabian knight (Dec 19, 2005)

Hooligan said:


> I think the "pimple" is more of a primer bulb to get fuel to the carb before the vacuum takes over rather than a choke mechanism.


 Yes you are correct. Even those engines that have the primer bulb ALSO have a Choke.
Even My Brand new weed eater that I just bought 2 days ago, has a "Choke" Plus the Primer Bulb,
So does my snowblower, so does my chainsaw.
It just makes life so much easier "Pushing" in some gas into the carb, then relying on the vacuum from a cold start.
I don't want to have to Pull Pull Pull. I have arthritis and I want the sucker to Start Right away, or as quickly as possible, and that primer bulb has allowed for easy starting.
I want to Pull once or twice and Start. Bingo. And when it is 20 below and you need to Blow Snow I want the blower to START NOW not after pull pull pull.


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## oldmanriver (Aug 1, 2004)

If you choke a Smurf what color will it turn ???


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## HermitJohn (May 10, 2002)

Hooligan said:


> Why would you want to vary the engine speed on a piece of equipment designed to perform its best at a specific rpm? Every engine that I have that is designed to be operate at various rpms has a choke/enrichener. Some of them have the primer bulb also and some don't. My 12 year old push mower has no choke/enrichener and starts every time after a few pushes on the primer bulb. It has a throttle if I need to adjust the motor speed but the governed speed at WOT seems right and works well. If you have to richen the mixture to get it to run right then there is a problem somewhere that you are masking.
> 
> I think the "pimple" is more of a primer bulb to get fuel to the carb before the vacuum takes over rather than a choke mechanism.
> 
> Like and outboard motor has. Both my outboards have enricheners and primer bulbs and I need to use both to cold start either of them.


Mowing weeds is different than mowing a golf course or yuppie lawn. In many situations a slower speed is better. I mow half throttle.


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## HermitJohn (May 10, 2002)

arabian knight said:


> Yes you are correct. Even those engines that have the primer bulb ALSO have a Choke.


If you actually look at the choke plate on carbs with both a choke and pimple, you will notice the choke is partially disabled by a rather large hole throught the choke plate. A partially disabled choke like this is not effective by itself.



arabian knight said:


> I want to Pull once or twice and Start. Bingo. And when it is 20 below and you need to Blow Snow I want the blower to START NOW not after pull pull pull.


An engine in good tune with a real choke can easily start and run with two pulls. A real choke, not one with a big hole in it will draw gas into carb a lot quicker than punching a plastic pimple a thousand times. Matter of fact with a REAL choke getting too much gas into the carb isnt that hard to do. 

Also with the plastic pimple method, unless you are going immediately to full throttle, the engine will stall in cold weather when first started. With a choke you can set it to be partially open so you dont go immediately from super rich to super lean. Engine has to warm up before you open the choke completely. The plastic pimple doesnt allow engine to warm up unless you have somebody running alongside the engine punching the pimple every little bit.


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## HermitJohn (May 10, 2002)

Hooligan said:


> Why would you want to vary the engine speed on a piece of equipment designed to perform its best at a specific rpm? Every engine that I have that is designed to be operate at various rpms has a choke/enrichener. Some of them have the primer bulb also and some don't. My 12 year old push mower has no choke/enrichener and starts every time after a few pushes on the primer bulb. It has a throttle if I need to adjust the motor speed but the governed speed at WOT seems right and works well. If you have to richen the mixture to get it to run right then there is a problem somewhere that you are masking.
> 
> I think the "pimple" is more of a primer bulb to get fuel to the carb before the vacuum takes over rather than a choke mechanism.
> 
> Like and outboard motor has. Both my outboards have enricheners and primer bulbs and I need to use both to cold start either of them.


You misunderstood what I said, maybe intentionally, the EPA doesnt want people using choke to enrichen their mandated settings. If you have to have the choke partially closed to run a warmed up engine, then indeed something is wrong. But PEOPLE DO IT so the pimple along with either no choke or a choke plate with a big hole in it is way to keep people from doing this. And modern small engines are set to run as lean as is possible, for pollution control, NOT for your ease of use. Engine running too lean has to run FULL governed speed to overcome this. Lot of them run like crap.

I take it you are not old enough to remember traditional chokes before the plastic pimples. No HOLES in them. Closed, they will suck all gas you need into an engine almost immediately as you crank. The choke plate blocks direct air flow from outside through the carb throat so instead draws fuel through fuel passages in carb. If anything you had to be careful to not flood engine. Getting plenty gas quickly was not a problem. Old engines if they didnt start immediately usually more an ignition problem. Remember those old timers used points and condenser which lot people didnt properly maintain and over years the magneto coil would get weak too.

If you look at your engines you say need both pimple and choke, then you will find a partially disabled choke, the manufacturer drills a big hole in the choke plate. This lets lot air through and doesnt let engine suck gas as effectively into the carburetor. These are pollution control designs to meet EPA demands, NOT there as an actual improvement.


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## Hooligan (Jul 18, 2007)

HermitJohn said:


> You misunderstood what I said, maybe intentionally, the EPA doesnt want people using choke to enrichen their mandated settings. If you have to have the choke partially closed to run a warmed up engine, then indeed something is wrong. But PEOPLE DO IT so the pimple along with either no choke or a choke plate with a big hole in it is way to keep people from doing this. And modern small engines are set to run as lean as is possible, for pollution control, NOT for your ease of use. Engine running too lean has to run FULL governed speed to overcome this. Lot of them run like crap.
> 
> I take it you are not old enough to remember traditional chokes before the plastic pimples. No HOLES in them. Closed, they will suck all gas you need into an engine almost immediately as you crank. The choke plate blocks direct air flow from outside through the carb throat so instead draws fuel through fuel passages in carb. If anything you had to be careful to not flood engine. Getting plenty gas quickly was not a problem. Old engines if they didnt start immediately usually more an ignition problem. Remember those old timers used points and condenser which lot people didnt properly maintain and over years the magneto coil would get weak too.
> 
> If you look at your engines you say need both pimple and choke, then you will find a partially disabled choke, the manufacturer drills a big hole in the choke plate. This lets lot air through and doesnt let engine suck gas as effectively into the carburetor. These are pollution control designs to meet EPA demands, NOT there as an actual improvement.



LOL

No why on earth would I want to "intentionally" misunderstand you? 

I fully understood what you meant. Unfortunately I am plenty old enough to remember traditional chokes. I have couple in the yard right now in fact. Ahhhh.... the good old days of stuck or broken choke cables. 

I am also very aware of the EPA regs requiring most engines to be set to run very lean. I just don't get how this has any significant affect on simple engines designed to be operated in a narrow rpm range. It does surely affect performance type engines which is why there is a billion dollar aftermarket business intended to supply us with the stuff we need to open those puppies up and let the fuel flow through.

Really don't understand the problem with a lawn mower though. Why on earth would you want to throttle it down to mow the heavy stuff? Manicured or golf course would never be used to describe our place. 

I understand that things are not as they were. I too am no supporter of the EPA in many cases.

Just haven't had the problems you seem to be having with my stuff.

Maybe there is some money in marketing a NOX system for your lawn mower.


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## HermitJohn (May 10, 2002)

Hooligan said:


> LOL
> 
> No why on earth would I want to "intentionally" misunderstand you?
> 
> ...


There are better choke cables that dont rust and bind. But if have one of the old spiral wire wound ones, just squirt some ATF or even motor oil on it once in a while. Called preventive maintenance. Rather than a cable I prefer a mechanical choke linkage on the engine itself. My ancient Yazoo mower, when Briggs went bad, I put a nearly new $40 Honda clone engine on it. Instead of a choke cable, I just used a length of baling wire to operate the choke like I did when getting rid of automatic choke linkage on the Briggs. Run it through bit rubber cut from an old radiator hose and it stays at any setting you want. Simple is always better. Engineers used to have the KISS principle (Keep It Simple Stupid). Now rule is make it as complex as you can and add a computer into the mix if possible and for sure whatever you do, dont make it repairable or at least not economically repairable.


I guess I need to turn the question around and ask why you would want to not have control over the rpm of your lawn mower? Do you think full rpm in all conditions is what you need? Have you ever tried running a mower at a slower rpm? I have never found it necessary to run full governed speed for any length of grass. Just wastes more fuel and makes mower noisier. Plus if you are in taller grass, it tends to be more apt to get long stringy lengths of grass wrapped around shaft. My old Yazoo doesnt grind up grass in to a wet pulp, it just cuts it and moves on. This takes LESS horsepower, a lot less horsepower. Think of it like running a brush hog at slower rpm with a sharp blade, run slow, you can make brush hog lay down tall stuff almost like a sickle mower. Well same with my old Yazoo.

I am not suggesting anybody do anything. I am simply stating what I have observed considering chokes and modern EPA engines. I will do everything possible to make the engines I own operate as I want them to operate. Just cause it comes from store set up a particular way, doesnt mean thats only or best way to do it. Usually just means its the way the manufacturer found to make the most profit without totally annoying either govt and consumer. Govt can close them down, but so can consumers, by not buying the product.

Any attempt at commercially selling products to circumvent EPA requirements is going to bite you in the rear. So is running a shop that modifies EPA systems to work better. Even the big corps need tag team lawyers and bunch lobbyists in Washington to avoid getting regulated out of buisiness. But re-engineering things yourself on your own off road equipment at this point is still under radar.


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## foxtrapper (Dec 23, 2003)

Choke useage varies on the engine. Fundamentally, a choke strangles air flow, increasing vacuum in the venturi, sucking in more gasoline, making the mixture rich. The degree of strangulation and resulting vacuum and resulting enrichment from that vacuum vary with how tightly the choke is closed, and how fast the engine is spinning.

Generally, you start a cold engine with full choke. When it starts, you will reduce the choke to get a smooth running engine. As the engine warms up, you can turn the choke off completely. 

One thing that makes many engines entertaining to start is that full choke causes the engine to flood. Then you have to greatly reduce the choke to restart the engine. The classic example of this with chainsaws and the like is them kicking and banging, and maybe even once catching for about half a second. They then flood. You reduce or turn off the choke, yank the string a few more times, and the engine bursts into life.

And then there are enrichener circuits. We can talk about them on another day.


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