# Surging (brand new) Powermore 272cc *solved* *updated*



## nitrous (Nov 17, 2021)

I've just picked up a brand new Yardman 26" blower with a 272cc Powermore engine on it. (Model 31AH5FKF501) The engine surges as soon as i turn the choke off, which leads me to suspect it's running too lean. I'm running brand new 87 octane fuel (Ethanol < 10 according to the pumps) and the fuel tank was completely dry and clean when I got it from the store.

Most of the posts I've found related to this issue involve older machines and most answers are some form of "clean/adjust/re-jet your carb". Since my carb appears to be non-adjustable and it really shouldn't be dirty, I'm wondering what my next steps should be. Spark plug gap was checked when I had a mean backfiring issue and found that it was way under-gapped, so I've resolved that but it did nothing for the surging/hunting issue.

Thanks in advance

Edit: turns out there must have been something plugging a jet or something in the carb. Even though I didn't find anything, a thorough cleaning and inspection of the carb resulted in it running absolutely smooth *aside from low idle with zero choke but I don't really care about that

Edit2: the issue seemed to recur after five to ten minutes of running each time I cleaned the carb, so I gave it one final chance with a small inline fuel filter. Now it purrs perfectly throughout the entire RPM range. Not a single spit or sputter, nor surges nor stutters. It idles right down to a smooth, quiet mutter.


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## LenD (Nov 17, 2020)

By no means an expert but: in all likelyhood you have a cheapo spark plug in there so replace that with quality plug per your manual. NGK is a great choice.

Also believe you should be using premium gas with 0% ethanol. Get it at Shell or Can Tire. ALL others have some level of that additive.

And fresh gas? Not leftover from last year?


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## nitrous (Nov 17, 2021)

LenD said:


> By no means an expert but: in all likelyhood you have a cheapo spark plug in there so replace that with quality plug per your manual. NGK is a great choice.
> 
> Also believe you should be using premium gas with 0% ethanol. Get it at Shell or Can Tire. ALL others have some level of that additive.
> 
> And fresh gas? Not leftover from last year?


Brand new gas from the Esso pumps just yesterday. Made sure the jerrycan was emptied of roughly one month old fuel first. I'll drain the tank and try some Shell premo, and get a new plug at the same time. Will report back with results. Thanks


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## nwcove (Mar 2, 2015)

just a suggestion..........get a set of micro drill bits and carefully drill out the main jet just a tiny bit.


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## Tseg (Jan 29, 2021)

I had a brand new Honda HSS724 that surged when cold once I moved the lever to full throttle out of choke-mode but evened out a bit after warming up. I switched a #75 main jet for #80 main jet at 600 ft. altitude and my surging disappeared and start up is more immediate.


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## EntropyKnower (Aug 27, 2021)

nitrous said:


> Most of the posts I've found related to this issue involve older machines and most answers are some form of "clean/adjust/re-jet your carb".


I've seen claims to the effect that carbs on newer machines are jetted too lean in attempts to satisfy emissions regulations. Maybe add some terms to your search queries to find info on that.


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## RIT333 (Feb 6, 2014)

In case you don't have mixture adjustment screws, you can try it out by giving it partial choke to see if that improved things.


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## nitrous (Nov 17, 2021)

EntropyKnower said:


> I've seen claims to the effect that carbs on newer machines are jetted too lean in attempts to satisfy emissions regulations. Maybe add some terms to your search queries to find info on that.


This is exactly what I'm finding. I live around 650ft above sea level so any lean condition from emissions goals would only be worse at this altitude.



RIT333 said:


> In case you don't have mixture adjustment screws, you can try it out by giving it partial choke to see if that improved things.


That's exactly what I did, on a fully warmed machine. Half choke runs a lot better. So much better that I did the rest of my snow moving at half choke. I'm thinking it's time to micro-drill the jet, but I still have to test out the other suggestions above (ZERO ethanol fuel, better spark plug at same heat and gap). I've already done 4 neighbor driveways and my entire back yard (room for small dogs to run) to test the dealer's theory of it needing to be broken in.

I know the up-to-E10 pump gas is bad for storage purposes because the ethanol tends to gum up the works so I'll run some of the Aspen long-term stable fuel through this thing before I start ripping the carb apart, just to make sure it's not some kind of ethanol issue in the carb even though it's fresh fuel. I've switched all my 2-stoke machines over to Aspen fuel years ago and I don't even bother draining the tank when I put em in storage. They just fire right up without issue after about 8 months (lawn trimmer). I just don't want to run that stuff through an engine that's going to burn literally ten times the amount of fuel unless it's storage time.


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## LenD (Nov 17, 2020)

This is for a not-so-new machine but may provide some tips


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## nitrous (Nov 17, 2021)

Well, looks like nothing else is working so it's time for jetting. The dremel drill bits I have don't go nearly small enough, and I haven't got anything else that might work. As much as I'd prefer to order a replacement jet, shipping and one jet will cost as much an an entire replacement carb from MTD. Looks like this is a #81 main jet. Any ideas on what size port that would be so I can order similarly sized microdrill bits?


















Measurements lead me to thinking it matches with Keihin 99101-124 jets (slow air jet for the FCR carb). Try as I might, I can't seem to find these in Canada.

Length 8.5mm
Shaft diameter 5.5mm
Thread diameter 6.9mm
Port like 0.4mm? Too small to measure lol


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## EntropyKnower (Aug 27, 2021)

nitrous said:


> ...
> Looks like this is a #81 main jet.
> ...


I think you should be looking more to the pilot/idle jet.

Look at the Donyboy video above, starting near 11:55 where he pulls the idle jet and it's way plugged up. The other cleaning he did in the video was good practice but probably didn't have much effect on the surging. He almost says that.

Can you find a whole set of small drill bits cheap?

If you need to measure a small hole, you might make a go/no-go gauge by sanding down something like a wire or a nail or a paper clip until it fits, then measure it with calipers.


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## nitrous (Nov 17, 2021)

EntropyKnower said:


> I think you should be looking more to the pilot/idle jet.
> 
> Look at the Donyboy video starting near 11:55 where he pulls the idle jet and it's way plugged up. The other cleaning he did in the video was good practice but probably didn't have much effect on the surging. He almost says that.
> 
> ...


Doesn't seem this carb has any other jets. The spot where you'd normally find the pilot jet looks like just a blank piece of aluminum in this case. Even in diagrams of very similar carbs, it looks almost identical except there's no pilot jet.










Great idea on the go/no-go piece. I'll give it a shot.


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## WrenchIt (Dec 6, 2020)

I'm not a fan of drilling jets larger unless replacements are readily available. And if alternate jet sizes were available, I'd be more inclined to buy them rather than play with those tiny tiny drills. (I once wanted to use a very small drill but found my chucks did not close down that tightly to grip it.)

I have two HS 621's and both surge for maybe 30 seconds to a minute. Once the engine warms up both run strongly at the recommended rpms (well, I just finished adjusting them, so I expect that).

I also think all this talk about E-10 gas/ethanol mix is much ado about nothing. I've run my tractor (Sears), Honda snowblowers, Toro snowblowers & mowers, Stihl chain saws, motorcycles, and cars on straight pump gas (small engines get Stabil in the gas, occasionally I throw in some Sea Foam (rarely)) for years with no problems. I try to use only Shell or Sunoco for the small engines - based not on fact but on what I've heard from others (anecdotal, but not from people I would consider experts). I've rarely had a problem that I could trace directly to the fuel. Sure, if I stupidly leave gas in an ICE's tank for 6 months or longer without using the motor, I'd expect problems - that's not the fault of the gas, but the operator. I also probably take better care of my tools than the average owner, but that's my choice. I never could understand laying out a lot of money for a tool and not caring for it with basic preventative maintenance.


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## orangputeh (Nov 24, 2016)

nitrous said:


> This is exactly what I'm finding. I live around 650ft above sea level so any lean condition from emissions goals would only be worse at this altitude.
> 
> 
> 
> ...


not sure if this was mentioned but micro drilling a jet usually makes things WORSE. the problem is elsewhere . dont have time to read every post.

Premium GOT


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## orangputeh (Nov 24, 2016)

WrenchIt said:


> I'm not a fan of drilling jets larger unless replacements are readily available. And if alternate jet sizes were available, I'd be more inclined to buy them rather than play with those tiny tiny drills. (I once wanted to use a very small drill but found my chucks did not close down that tightly to grip it.)
> 
> I have two HS 621's and both surge for maybe 30 seconds to a minute. Once the engine warms up both run strongly at the recommended rpms (well, I just finished adjusting them, so I expect that).
> 
> I also think all this talk about E-10 gas/ethanol mix is much ado about nothing. I've run my tractor (Sears), Honda snowblowers, Toro snowblowers & mowers, Stihl chain saws, motorcycles, and cars on straight pump gas (small engines get Stabil in the gas, occasionally I throw in some Sea Foam (rarely)) for years with no problems. I try to use only Shell or Sunoco for the small engines - based not on fact but on what I've heard from others (anecdotal, but not from people I would consider experts). I've rarely had a problem that I could trace directly to the fuel. Sure, if I stupidly leave gas in an ICE's tank for 6 months or longer without using the motor, I'd expect problems - that's not the fault of the gas, but the operator. I also probably take better care of my tools than the average owner, but that's my choice. I never could understand laying out a lot of money for a tool and not caring for it with basic preventative maintenance.


You're bucking for GOT status but there will only be ONE Premium GOT.


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## orangputeh (Nov 24, 2016)

nitrous said:


> Doesn't seem this carb has any other jets. The spot where you'd normally find the pilot jet looks like just a blank piece of aluminum in this case. Even in diagrams of very similar carbs, it looks almost identical except there's no pilot jet.
> View attachment 183228
> 
> 
> ...


PILOT JET and dont drill out GD it.


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## WrenchIt (Dec 6, 2020)

orangputeh said:


> You're bucking for GOT status but there will only be ONE Premium GOT.


LOL, you've got me wrong. First, I have no interest in giving you competition as the GOAT* GOT; I'm neither grumpy, nor old (though I think I'm older than you). I'm just trying to tell it how I see it, and use a bit of common sense. Too many of us tend to believe stuff which has no basis in fact, is contrary to common sense, yet we steadfastly cling to these beliefs - dang the torpedoes, full speed ahead.

Gas/Eth E10 is a perfect example.

*GOAT = Greatest Of All Time


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## nitrous (Nov 17, 2021)

orangputeh said:


> PILOT JET and dont drill out GD it.


Wait, pilot jet where? I thought that was the main jet in the center. The spot to the right of center in that picture has nothing in it. I'm assuming the same aluminum cast is used for carbs that do have a pilot jet, just that it hasn't been machined into this model.

I'll order a few sizes larger jets as I'm paying about $40 for shipping a small envelope of jets that cost $10 each. Should be here in time for next winter, so I'll just run er choked until then.

Unless there are other ideas? Like I said in the original post, this is a brand new unit. With a freak snowfall up here and the all-too-common supply chain issues these days, I'd probably spend the rest of the winter without a snow blower if I return this one.


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## tabora (Mar 1, 2017)

nitrous said:


> Wait, pilot jet where?


The pilot (low speed) jet is typically on the top of the carb, and is often mostly plastic these days. It's below the main jet and nozzle in this picture:
















Drilling a main jet often ruins it and causes it to spit fuel rather than atomizing it. The jet has an engineered venturi in it. Here's an example:


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## nitrous (Nov 17, 2021)

tabora said:


> The jet has an engineered venturi in it.


Okay, I was so sure that was the case until I've read so many posts on many different forums, as well as many YouTube videos, about drilling out the main jet. Yup, definitely not gonna touch that one with a drill.



If the surging happens throughout the entire rpm range, wouldn't that suggest the issue is with the fuel ratio? And choking the (warmed up) engine solving the issue would mean that, since removing air fixes the issue, then the issue is running too lean? **Edit: it runs exactly like the unit in the video above at the 40 second mark.

As I decrease throttle to the low end with the choke off, the surging gets more drastic. Simply adding choke smooths it right out. And at high end, the surging is still very drastic without choke, just that it's surging further from zero rpm.


Also, do these things not come with an air filter? There's just a little plastic shield about 7mm away from an open carb and choke plate. No screen of any sort and nothing that looks like anything is missing.


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## orangputeh (Nov 24, 2016)

nitrous said:


> Wait, pilot jet where? I thought that was the main jet in the center. The spot to the right of center in that picture has nothing in it. I'm assuming the same aluminum cast is used for carbs that do have a pilot jet, just that it hasn't been machined into this model.
> 
> I'll order a few sizes larger jets as I'm paying about $40 for shipping a small envelope of jets that cost $10 each. Should be here in time for next winter, so I'll just run er choked until then.
> 
> Unless there are other ideas? Like I said in the original post, this is a brand new unit. With a freak snowfall up here and the all-too-common supply chain issues these days, I'd probably spend the rest of the winter without a snow blower if I return this one.


pilot jet
pilot jet
pilot jet


jeremy crickets

watch some you tube grasshopper


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## tabora (Mar 1, 2017)

nitrous said:


> As I decrease throttle to the low end with the choke off, the surging gets more drastic.


The pilot jet supplies fuel throughout the throttle range, then the main jet adds fuel on top of it. Listen to @orangputeh, please, before he becomes a GOT.


nitrous said:


> Also, do these things not come with an air filter?


Not much dust/dirt to filter in a snow storm, and they could ice up in extreme conditions, so no air filter.


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## EntropyKnower (Aug 27, 2021)

nitrous said:


> **Edit: it runs exactly like the unit in the video above at the 40 second mark.


If it surges that bad, I think it's more than a slightly undersized jet. I would expect it's somehow pretty seriously plugged. The pilot circuit that is. The pilot jet or some part of the fuel path in the idle/pilot circuit. Check the bore near the throttle plate. Are there two or three little holes? If so, make sure those are clear. Remove the pilot jet and spray some cleaner in the hole that you removed it from and look for flow through those little holes.


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## nitrous (Nov 17, 2021)

EntropyKnower said:


> If it surges that bad, I think it's more than a slightly undersized jet. I would expect it's somehow pretty seriously plugged. The pilot jet, that is.


Everything is absolutely spotless. Not so much as a spec of any debris or anything throughout the carb, in the float bowl, or coming out of the fuel tank. This thing was brand new and the fuel system hadn't seen any fuel until I put some into the tank. Plus, I've drained the tank a couple times: once to try zero ethanol fuel and again to remove the carb for inspection. Nothing clogging the fuel line either. 

I've also seen another post where inadequate fuel cap venting was the suspected issue, so I tried pulling the cap off and that changed nothing.

So, aside from doing what every YouTube video I've seen so far seems to suggest (cleaning out the jet which isn't dirty in this case, or drilling out the jet which doesn't seem like the best idea for fuel atomization), I'm guessing there's no other way to adjust the carb short of buying a bunch of different jets.

Edit: I posted too soon lol. I'll test spray some cleaner through the jet and see how it flows.


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## orangputeh (Nov 24, 2016)

tabora said:


> The pilot jet supplies fuel throughout the throttle range, then the main jet adds fuel on top of it. Listen to @orangputeh, please, before he becomes a GOT.
> 
> Not much dust/dirt to filter in a snow storm, and they could ice up in extreme conditions, so no air filter.


"you can lead a horse to water.........."

you gotta pic of the pilot jet ON the carb? of course it could be sumting else but am trying to cover all the bases. 

it could also be the flux capacitor circuit inside the defillibrator..that i will need soon.....


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## jherbicide (Oct 14, 2021)

Take and post pictures of both sides of the carb and we can point you to where the pilot jet resides.


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## WrenchIt (Dec 6, 2020)

nitrous said:


> So, aside from doing what every YouTube video I've seen so far seems to suggest (cleaning out the jet which isn't dirty in this case, *or drilling out the jet*


There are a lot of youtube videos that are garbage. If there are a bunch advocating drilling the jet for your year, make and model snowblower, then after you get this sorted out you can go back to the old configuration of the carb and drill the main jet (you will have the one that worked as a backup, so nothing will be lost). Let us know what you discover.

If this is a brand new machine, why don't you take it back to the dealer or at least burn up the phone lines to Yardman customer service? Isn't there a warranty? Nobody in his right mind believes constant surging is correct carburetion for a small engine.


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## nitrous (Nov 17, 2021)

orangputeh said:


> "you can lead a horse to water.........."
> 
> you gotta pic of the pilot jet ON the carb? of course it could be sumting else but am trying to cover all the bases.
> 
> it could also be the flux capacitor circuit inside the defillibrator..that i will need soon.....





jherbicide said:


> Take and post pictures of both sides of the carb and we can point you to where the pilot jet resides.


Bottom with float bowl valve and one jet










And top with that little plastic Hasbro toy air jet underneath the black plastic retainer screw.


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## tadawson (Jan 3, 2018)

On a Honda (or clone) carb, the brass one in the bowl is the main, and the plastic on top is the pilot . . .


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## jherbicide (Oct 14, 2021)

I’m also starting to wonder if this thing doesn’t have a true pilot jet too. Traditionally they are between the throttle butterfly and the engine. Are there any Welch plugs on the sides here?










if not, I’d suspect that plastic “air” jet up top is your culprit.


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## tabora (Mar 1, 2017)

jherbicide said:


> Take and post pictures of both sides of the carb and we can point you to where the pilot jet resides.


I already showed him where the pilot jet is back in post #19...


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## jherbicide (Oct 14, 2021)

tabora said:


> I already showed him where the pilot jet is back in post #19...


Yep, I missed that.


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## nitrous (Nov 17, 2021)

jherbicide said:


> I’m also starting to wonder if this thing doesn’t have a true pilot jet too. Traditionally they are between the throttle butterfly and the engine. Are there any Welch plugs on the sides here?
> 
> View attachment 183247
> 
> ...


That's why I was calling the brass part the main jet. I'm used to the pilot being (or at least feeding) between the throttle butterfly and the engine. There's not a single Welch plug on it, but there are a couple brass plugs that would be for closing machining routes that need to be sealed after machining was complete. 

As for the little plastic guy on top, I took a better look at it. That isn't an air jet at all, and I must have been too tired at that point to not notice that there's no port in the top of it and there are ports inside it. It pulls fuel from _after_ the brass jet and feeds this guy that comes out between air filter and choke plate on the right side in this picture.










So the center brass piece would be one jet (long piece in picture below), the plastic piece another jet. Since that little threaded brass piece meters fuel to both circuits, increasing the port size would add fuel and richen the entire RPM range.









So, by all the articles about carb jetting that I've found so far, the brass piece between the throttle and choke butterflies would be the pilot jet (fuel through entire rpm range) and the plastic one would be the main jet (only adds fuel at upper rpm range, and high rpm would be needed to create enough vacuum for that jet to pull any fuel). The brass piece stamped 81 would be in place to limit fuel flow to both jets. At least, that's what my monkey brain thinks.


Any thoughts?


And yes, every single orifice is absolutely clear and spotless clean. I'm going to reassemble and fuel er up again just in case there was something I unknowingly dislodged from one of those orifices in the process.


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## orangputeh (Nov 24, 2016)

post #31 shows the location of pilot.

see that black screw? remove that. then lift top piece on top off.( if relevant ) The pilot jet is pressed into the carb case and you can carefully pry it out with a small screwdriver.
You can spray some compressed air or carb cleaner into bottom of jet and the liquid should spray out easily thru side holes.

an important thing to inspect is the small O ring on the pilot jet. It should be round and not flat or damaged. on a Honda carb they are 1mmX4mm Oring.This may need to be replaced.
If the jet is clogged be very careful cleaning with a wire. I use a very thin carb cleaner tool that won't enlarge or damage the opening.

Like I said before this may not be the problem. I do most carb cleaning without removing the carb. I also will spray carb cleaner around the gasket area while engine is running and if the the engine increases in RPM's then I know I have a leak somewhere. Maybe it is not tight or the gasket needs replacing.

With this jet out spray carb spray into that small hole to clean that out also. There are tons of carb cleaning videos on you tube for every model small engine that shows all this.

The main thing on carb cleaning is PATIENCE.

Any kind of surging/hunting/running on any kind of choke is a fuel blockage somewhere or an air leak ( as far as I know )

I forgot to ask something. Is this the original carburetor or an aftermarket clone? Some aftermarket carbs I have used surge right out of the box. The pilot jet opening is too small and I change them out with a OEM pilot. ( original ).

check back. you'll get this eventually.






see , I can be nice sometimes.......


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## jherbicide (Oct 14, 2021)

Without actually seeing and holding that carb in my hands, I can’t be 100% or even close to certain for the below:

That brass hole on the right side of your appears to be part of the air mixture circuit. Air mixture circuits are almost always only part of the idle circuit.

Idle circuits can pull fuel thru the main jet orifice, as you somewhat describe. They use the air mixture circuit to assist.

You have to remember, when throttle is closed the vacuum level is very high *behind *the throttle butterfly. When the throttle butterfly is opened, the area of high vacuum shifts to the Venturi. In a very simplistic way that is how carbs switch between circuits.

For what I suspect the design of this carb, for idle conditions it uses an air mixture circuit to pull fuel thru the main jet.


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## nitrous (Nov 17, 2021)

orangputeh said:


> post #31 shows the location of pilot.
> 
> [Etc]


Yup, did all of that already. And just inspected those o-rings because I didn't think of that. Everything is flowing well. I guess there's really nothing left but to test again.


As for carb, it's factory original but it is HuaYi brand, for what it's worth. I'm guessing that would be about equivalent to aftermarket clone. And the pilot jet is incredibly small on this guy.


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## nitrous (Nov 17, 2021)

jherbicide said:


> Without actually seeing and holding that carb in my hands, I can’t be 100% or even close to certain for the below:
> 
> That brass hole on the right side of your appears to be part of the air mixture circuit. Air mixture circuits are almost always only part of the idle circuit.
> 
> ...


Oh! Yeah that makes sense, and would also explain how there's such a small orifice in the plastic jet as air would pass through it a lot easier than fuel.


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## Ziggy65 (Jan 18, 2020)

WrenchIt said:


> If this is a brand new machine, why don't you take it back to the dealer or at least burn up the phone lines to Yardman customer service? Isn't there a warranty? Nobody in his right mind believes constant surging is correct carburetion for a small engine.


YES
Have you contacted the dealer/store were you bought the machine?

What was their response? 

This is a brand new machine with a warranty (which you will be voiding if you are drilling/changing carb parts). The surging is an issue, have them fix it or replace the machine or get your money back and buy a different or better machine (Toro, Ariens).


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## jherbicide (Oct 14, 2021)

jherbicide said:


> Without actually seeing and holding that carb in my hands, I can’t be 100% or even close to certain for the below:
> 
> That brass hole on the right side of your appears to be part of the air mixture circuit. Air mixture circuits are almost always only part of the idle circuit.
> 
> ...


Here a crude pictorial concept behind my previous jibberish. 

Blue is air, red is gas. Flow is left to right.


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## nitrous (Nov 17, 2021)

Ziggy65 said:


> YES
> Have you contacted the dealer/store were you bought the machine?
> 
> What was their response?
> ...


Haven't bothered as I'm too stubborn. Just tested and somehow everything works perfectly smooth now, except at low idle when there's no choke. I've really got no reason to be at low idle without the choke as it's going to be warmed up and go time when I take the choke off anyway.

So I guess my solution to this entire problem was "Clean the carb". I just don't know where it was plugged with anything, but ports that small throughout a little carb and its easy to miss one tiny fleck of _something _plugging up the works.

A big thanks to all of you for educating and assisting me through this process. I appreciate all your help.


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## orangputeh (Nov 24, 2016)

sorry if i didnt see your post about already doing this. I dont read every post.
even though retired i make 3 - 4 time more money with my snowblower hobby than i ever did at regular jobs 
so once in awhile i take a break and check up here to see if i can be of any help.


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## nitrous (Nov 17, 2021)

orangputeh said:


> sorry if i didnt see your post about already doing this. I dont read every post.
> even though retired i make 3 - 4 time more money with my snowblower hobby than i ever did at regular jobs
> so once in awhile i take a break and check up here to see if i can be of any help.


All good. You ended up hitting something that I missed checking, so all the better that you did post it all. You and so many others were a big help. Thanks


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## Shovel (Mar 26, 2019)

Without reading the entire thread...so I dont know if it's been mentioned..I suspect a small piece of debris in the pilot jet is the culprit...if the engine falls on load its the main..if it surges Without load its the pilot...as the carb butterfly is just barely open under no load with full throttle anyway.
My machine will hunt and surge for a bit until it's warmed up good..one click of choke fixes it for me..then I can turn the choke all the way off after a while..In Temps just below freezing..I can turn the choke off alot sooner than say at ten degrees.

Sent from my SM-A115U1 using Tapatalk


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## orangputeh (Nov 24, 2016)

Shovel said:


> Without reading the entire thread...so I dont know if it's been mentioned..I suspect a small piece of debris in the pilot jet is the culprit...if the engine falls on load its the main..if it surges Without load its the pilot...as the carb butterfly is just barely under no load with full throttle anyway.
> My machine will hunt and surge for a bit until it's warmed up good..one click of choke fixes it for me..then I can turn the choke all the way off after a while..In Temps just below freezing..I can turn the choke off alot sooner than say at ten degrees.
> 
> Sent from my SM-A115U1 using Tapatalk


Excellent points. My old 80 is like that. Once it warms up it stops surging at idle.


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## LenD (Nov 17, 2020)

AFAIK, although you said the tank was clean/dry, prior to every delivery (unless you brought it home still in the box), they do put a small amount of gas in there just to make sure it runs. But do they run it dry??

When was that done? Who knows but.........


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## nitrous (Nov 17, 2021)

Edited first post in thread and bumping in case others have recurring issues like I did.

TL;DR- probably a lot of something incredibly tiny in my jerrycan or fuel tank that gets into the carb but it's fixed for good with an inline fuel filter.


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