# Running Carb Dry



## Elt31987 (Sep 6, 2015)

So it seems to be the consensus that when your done with your snowblower and want to store it for a few days, weeks whichever that you should turn it off by turning off the fuel shutoff valve and allow it to die that way the fuel is removed from the carb. Seems perfectly logical. My question is, do you turn it off when it begins to surge (IE its very low on gas) or allow it to fully die on its own. Reason i ask is because the LCT GEN III manual says to turn it off when it begins to surge to avoid engine damage. They also say before turning off the fuel valve to lower the RPMs to its lowest setting. Thank you!


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## sscotsman (Dec 8, 2010)

It's not the consensus to do this *every* time you shut down the snowblower..there is no need for that. During the regular winter season, just shut it down normally, without running the carb dry..(that also makes starting it again easier, because there is still gas in the carb.) Thats perfectly fine and the "normal" way to do things..

The "running the carb dry" thing really only needs to be done one time a year, when you are storing the snowblower for the spring/summer/autumn, after the last use of the winter.

I dont believe it would cause any engine damage to allow it to run out of fuel..its running out of gas, but not out of oil, lubrication should still be fine.

One thing to consider though: small gas engines, like on snowblowers are lawnmowers, are designed to run best at FULL RPM's! full speed is better than slow idling, because the splash lubrication and the engine cooling both rely on full-rpm's to work properly..

Running at a prolonged slow idle is more of an issue for a summer-use lawnmower than a snowblower, because over-heating is less of a concern in the winter..but still, a prolonged slow idle is generally not a good idea..(we are talking 5 to 10 minutes or more..slow idling for a minute or less is fine.)

I would drain the tank as much as possible..then you are only left with fuel in the gas line and the carb..
start the engine..let it run at a fast clip until it starts to sputter..shouldnt take long at all..then turn down the idle slower until it sputters out and stalls on its own.
People have been doing it this way for 3/4 of a century..never heard of any problems related to it.

Scot


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## Elt31987 (Sep 6, 2015)

Appreciated.


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## NJHonda (Feb 8, 2013)

Letting an engine die via shutting off the fuel will never hurt it. It simply runs out of gas. The oil is still being splashed in the crank case so its no issue.


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## chrisexv6 (Feb 4, 2014)

I only run mine out at the end of the season. During the season, if we are lucky enough to get a two or more week long stretch without snow, Ill go and start it up just to get everything sloshed around a bit.

At the end of the season I pull the fuel line off the bottom of the tank and let the leftover fuel drain into a fuel jug. Replace the fuel line onto the tank then run a mixture of fresh fuel, Marine Stabil, Seafom and MMO for a few minutes. That way I know whats in the carb is mostly stabilized and "cleaner". This has worked for the 10 years Ive had my Ariens.....when starting for the next season it always starts on the first pull (provided I dont flood it!)


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## Kiss4aFrog (Nov 3, 2013)

If you really want to get crazy you can also try to start it with the choke on to suck out the most you can and pull the fuel bowl and wipe it dry.


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## Elt31987 (Sep 6, 2015)

Thanks for all of the ideas! I run MMO on all of my gas engines every fill up so hopefully keeping things shiny and clean!


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## Shryp (Jan 1, 2011)

Kiss4aFrog said:


> If you really want to get crazy you can also try to start it with the choke on to suck out the most you can and pull the fuel bowl and wipe it dry.


I will actually slowly add choke as it starts to sputter and surge. Just keep adding enough choke to make it run smooth again. Eventually you will be at full choke and it will completely die.


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## NJHonda (Feb 8, 2013)

Shryp said:


> I will actually slowly add choke as it starts to sputter and surge. Just keep adding enough choke to make it run smooth again. Eventually you will be at full choke and it will completely die.


exactly what I do


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## MuncieM22 (Jul 28, 2012)

Me too *Shryp*, and every time also..........makes me feel better.... still waiting for snow. Four machines and no removable snow yet, I've never seen it like this in the 43 years I've had this house. ......:icon_blue_very_sad:


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## Normex (Feb 21, 2014)

Just wanted to add that it is not a one size fit all concerning engine shut offs at end of season, here in Ontario Canada for some reason our regular gaz with ethanol seems to be of higher quality where I always leave the tank full with some Stabil and close the fuel shut off valve for the 6 months of summer storage and the engine starts readily come fall. Good Luck All


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## shallowwatersailor (Feb 19, 2013)

I just finished cleaning the last of our 35.2" snow from the 2016 Blizzard. I added over five hours to the hour meter. 

Because our snowfall (nothing forecast for the next ten days) is sporadic, I always shutoff the fuel and let the engine run out of fuel. But the tank has the fuel left in it as the Premium gasoline is treated with _Marine Stabil_ and _MMO_. The diesel fuel has _Power Service Diesel Kleen_. When I prepped it and my tractors Thursday for the storm, they were just topped off with fresh Premium for this year. It hadn't been run since last March. Popped off with the first crank!


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## nograin (Jan 27, 2016)

Normex, Your fuel in Canada is a bit different, in part due to different regulations on your side of the border. Our lower 48 fuel also varies from region to region and seasonally. Some of that is regulatory, some is a combination of performance, industry requirements, and economics. 

That said, all 'gasoline' is a combination of stuff. The different components evaporate at different rates. Our winter fuel (and probably yours too) is allowed a higher Reid Vapor Pressure than summer. That makes it easier to start in the winter (and is cheaper to make, if I recall correctly increasing benzene is one of the ways this is done). However the really light stuff will evaporate in warmer weather. So some percentage of the fuel goes away over time and sometimes varnishes form.

This is a very long way of saying old fuel is never as good as fresh. Whether it is so bad as to not run is another matter. My sno-thro ('68) would never fire up if I didn't clean the carb first regardles of additives or running it dry. Last winter I bought vp small engine fuel and haven't had a problem since. This year I'm trying eth free 91 and so far so good, but its still pump gas so I'm going to drain any left over. I don't think there is a right or wrong, just do what the engine tells you.


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## Cardo111 (Feb 16, 2015)

Elt31987 said:


> So it seems to be the consensus that when your done with your snowblower and want to store it for a few days, weeks whichever that you should turn it off by turning off the fuel shutoff valve and allow it to die that way the fuel is removed from the carb. Seems perfectly logical. My question is, do you turn it off when it begins to surge (IE its very low on gas) or allow it to fully die on its own. Reason i ask is because the LCT GEN III manual says to turn it off when it begins to surge to avoid engine damage. They also say before turning off the fuel valve to lower the RPMs to its lowest setting. Thank you!


My Ariens has the Gen III motor, I love the low profile design but hate the poorly designed gas cap and relatively small gas tank to engine size ratio.

My Honda lawnmower states the same thing in the manual regarding shut off when it surges to prevent engine damage, yet another way for the corporate lawyers to help the manufacturer cover their arse.


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## Town (Jan 31, 2015)

While I empty the entire fuel system at the end of the season, during the season I just switch the engine off and then close the fuel valve to reduce the possibility of leaks. I don't think that any harm would come to the fuel system for a few days or weeks between usage. I use premium gas which is ethanol free to minimize ethanol effects. 

My car has fuel injection and stores quite a bit of gas in the injectors and fuel manifold and it uses regular gas with 10% ethanol. It can sit for several days without being used. To drain the fuel system on my car would be a major task every time I used it. In years gone by we had carbs on our cars and we never drained them either between uses. There just isn't any negative issues with leaving gas sit for a few days or weeks or even a month or so. The only problem with a month of non use is whether the battery will be drained or not.

It seems that the idea of draining gas from a snowblower carb by whatever means is more because it is easy to do than it actually helps anything. 

Just my opinion.


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## nograin (Jan 27, 2016)

I just was looking at my Snow King manual and noticed they recommend draining the gas tank and the carburetor bowl for long term storage. They define that as 30 days. Interesting the illustration (and text) show the carburetor bowl came with a drain. The booklet is the 1-66 Revision. My engine was built August 1967, and the carb bowl doesn't have that feature. 

I only run the carb dry or drain at the end of the winter, and as stated in my previous post, I haven't had to clean the carb since switching fuel. I also changed the fuel line that the reformulated fuel was causing to disolve internally. 

Carburetor cars, especially with moderate to high compression and open fuel systems do not like today's winter fuel in the summer. I can tell you this from experience. I used to always keep fuel tanks full to reduce condensation. Now I weigh the pros and cons based on the next time I expect to use the vehicle and where it is being parked. Its not much fun siphoning off fuel...


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## Earl (Nov 29, 2016)

How much MMO do you add to your tank on a fill-up?
Thanks


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## NJHonda (Feb 8, 2013)

Shryp said:


> I will actually slowly add choke as it starts to sputter and surge. Just keep adding enough choke to make it run smooth again. Eventually you will be at full choke and it will completely die.



This is what I do


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## Taurus04 (Dec 10, 2014)

Earl said:


> How much MMO do you add to your tank on a fill-up?
> Thanks


The ratios is 2 ounces per 5 gallons gas suggested on "Bob is the OIl guy" That is what I use or one ounce per gallon Seafoam.


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## iaminsider (Nov 7, 2016)

I have only ever run my carb dry after the season is over. I do however ALWAYS use ethanol free fuel in my small engines.


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## kNewc (Nov 22, 2016)

I think draining is more for the 2 stroke machines as the gas would evaporate and leave the oil residue. Modern 4 strokes obviously do not have oil in the fuel so this isn't an issue anymore. When I worked at Sears their service department would say to leave gas in but to add stabilizer. The pretty big consensus on this site is to drain and then run dry - but for 4 strokes I don't see that being an issue.


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## mrfixit (Dec 3, 2016)

What is MMO?


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## MuncieM22 (Jul 28, 2012)

Marvel Mystery Oil..........I use it all the time in my OPE fuel with stabilizer:wink:


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## New_HondaHS35 (Jan 18, 2014)

no reason to drain it dry unless you won't be using it for a few years. I run true fuel for mt last couple tanks.


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## New_HondaHS35 (Jan 18, 2014)

mrfixit said:


> What is MMO?


B.I.B.

Bull.... in a bottle


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## Prime (Jan 11, 2014)

MuncieM22 said:


> Me too *Shryp*, and every time also..........makes me feel better.... still waiting for snow. Four machines and no removable snow yet, I've never seen it like this in the 43 years I've had this house. ......:icon_blue_very_sad:[/qu
> 
> Yes. I don't ever recall a winter with so little snow here. Still could have alot of winter over the next few weeks. 2 years ago we had the worst winter in many years and it only started late Jan. Heavy rain here today.


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## Sid (Jan 31, 2014)

I always run the SB dry after every use, because we don't get a lot of storms on LI so I treat each storm as the last one. Works for me.
Sid


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## Sid (Jan 31, 2014)

I run my SB dry after each storm because we don't get many storms on LI, it works for me.
Sid


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## 524SWE (Jan 20, 2017)

from Marvel Mystery Oil's own MSDS it looks to me like it's mostly Naptha and Stoddard Solvent.

Component Concentration (wt%) 

Petroleum Distillates 
(Hydrotreated Heavy Naphthenic) 60-100% 

Petroleum Distillates 
(Stoddard Solvent) 10-30% 

Tricresyl Phosphate 0.1-1.0% 

Ortho Dichlorobenzene 0.1-1.0% 

Para Dichlorobenzene <0.1%


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## Elt31987 (Sep 6, 2015)

Ive been running it dry after each use. Takes but a minute. As it starts to sputter, ill choke it a little, and repeat until it dies. Again, likely not needed, but for the minute it takes its more of a peace of mind and she always fires right up the next time i use her.


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## MuncieM22 (Jul 28, 2012)

I'm with Elt31987, I've been doing this since my first snow blower (1979) and most of my other machines if possible. I drop the bowl after the season is done and drain the gas tank(s) also. Better safe then sorry??!!:icon-cheers:


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