CHAINSAW CARBURETOR LEAKING GAS/FLOODING: Why Carburetor Overflow?

An Enlightening Explanation covers what ACTUALLY Causes an Engine to Flooding, for Quick Troubleshooting, Optimal Performance, Preventative Maintenance, Cost Savings, Environmental Impact and Safety.

- So let's begin: Two-stroke engines can flood for several reasons, and it's important to understand these causes to prevent or address flooding effectively. Engine flooding occurs when there is an excessive amount of fuel in the combustion chamber or crankcase, hindering the engine from starting or running properly. Here are the primary reasons for flooding in two-stroke engines:

Over-Choking: One common reason for flooding is over-choking the engine. When you pull the choke lever or prime the engine too many times before starting, you enrich the fuel mixture excessively. This leads to an overabundance of fuel in the combustion chamber, making it difficult for the engine to start.

Repeated Failed Start Attempts: Multiple attempts to start the engine without allowing it to clear excess fuel can result in flooding. If the engine doesn't start after several pulls of the starter cord, additional fuel may accumulate in the chamber.

Fouled Spark Plug: A fouled spark plug, typically caused by carbon buildup or oil deposits, can lead to incomplete combustion. This, in turn, can cause fuel to accumulate in the chamber, resulting in flooding.

Carburetor Issues: Problems with the carburetor, such as a sticking float or needle valve, can prevent the carburetor from properly regulating fuel flow. This can lead to an excessive amount of fuel being introduced into the combustion chamber.

Air Intake Restriction: If the air filter is dirty or blocked, the engine may receive insufficient air, disrupting the air-fuel balance. The result can be an overly rich mixture and flooding.

Improper Mixing Ratio: Using an incorrect oil-to-gasoline ratio in the fuel mix for two-stroke engines can lead to incomplete combustion and fuel buildup.

Low Compression: Low compression in the engine may hinder the expulsion of exhaust gases and the intake of fresh air-fuel mixture. This can result in incomplete combustion and flooding.

To prevent or address flooding in a two-stroke engine:

Avoid over-priming or over-choking the engine.
Allow the engine to clear any excess fuel between starting attempts.
Regularly maintain and clean the spark plug.
Inspect and service the carburetor as needed.
Keep the air filter clean and unobstructed.
Ensure the correct oil-to-gasoline ratio in the fuel mix.
Address any compression issues by checking for worn piston rings or cylinder damage.
Proper maintenance and starting procedures can help minimize the risk of flooding and ensure your two-stroke engine runs smoothly.

This principle works for most types of Chainsaw saws, and the following also helps with Chainsaw maintenance. So, whether you are using a Stihl Chainsaw, Husquvarna Chainsaw, basically, all types of Petrol Chainsaw are valid for this principle, as well as many types of or a 2 Stroke Engine. The Electric Chainsaw, of course, escapes this whole principle!

Thank you so much for watching

#EngineFlooding
#TwoStrokeEngine
#StartingProblems
#EngineMaintenance
#CarburetorIssues
#SparkPlug
#AirFilter
#FuelMixing
#EngineCompression
#MechanicalIssues
#PreventFlooding
#EngineTroubleshooting
#EngineRepair
#FuelSystem
#SmallEngineProblems
#EngineFloodPrevention
#MaintenanceTips
#OutdoorPowerEquipment
#StartingTroubleshooting
#floodedengine
The creation of information in this description was helped by ChatGPT

[paulcombes]

Excellent video, and thank you for your extensive diagrams helping others see some of the common causes of a "wet" combustion chamber . You are a great educator .

[joebuttas]

Wow, this is why I love youtube. Thank you for the time and effort you've put in to this for us.

[souldrinker]

No doubt you recognise my name by now; so prepare for more fanboying. Fantastic video once again, I don't know what else to say other than please keep making videos, you're such a fantastic teacher and an invaluable recourse to students of Mechanical Engineering like myself.

[haeke]

Best explanation ive seen . Understanding the theory really is the difference between becoming an expert and just being a user. Now I know how to diagnose and determine what is going on when problems arise . Thankyou sir. Look forward following more tutorials

[cookiemonster]

25 years in grounds, starting with little old lady's yards, up to the manager of grounds at large university in southern USA servicing at PGMA levels 1 & 2 in commons of main and 4 satellite campuses, in addition to sports venues of 5 nationally ranked collegiate level athletic programs, and have secretly been woefully lacking in skill when dealing with two stroke engines having carb trouble. With your being willing to share your knowledge, I will now most certainly be able to master this shortfall in the presence of my staff. God bless you sir, and many thanks!

[martinfinster]

Fantastic editing and visual demonstrations. I've been repairing machines of all kinds since a small lad and I learned something. I just went psychotic on a small trimmer (threw it across the lawn) that's flooding and came inside to check youtube and here you are settling me down. Well done!

[roymg]

I've fought with these little carburetors many times talking them apart cleaning and installing kits but I never dreamed there was so much detail to be had with these things until now. Thanks for the lesion.

[tomharries]

absolutely amazing video I cannot thank you enough. I work in a garden machinery workshop and these small things were not taught when I was learning. I can fix 98% of machines but recently had a kawasaki hedgetrimmer which was flooding excessively. I tried a new set of fuel lines as the old ones were perished, a new fuel filter, a carb overhaul kit and it's still flooding. you can pull it over and leave it and the fuel will still come out of the air filter housing and into the cylinder. after watching this I am definitely going to look at the metering diaphragm and needle assembly as it is most likely this.
again thank you for your help and I will continue to watch your videos as they are so well set out and uncomplicated.

[aegairsoft]

Thank you very much! This is just what I was looking for, a well spoken and informative lesson on troubleshooting engines, consumable by newbies like me. I will definitely be watching your other videos.

[Rick-tdqh]

After many frustrating failed attempts to get my 2 stroke line trimmer working, these valuable and brilliantly presented insights got me over the line. Believing that I understood 4 stroke engines pretty well, I wrongly imagined that a two stroke engine would be a pushover. These great videos have shown me how a failure in one part can easily look like a fault in the other. I'm still not sure of the root cause in my case, best guess it got chronically flooded due to old fuel. I went straight to the ignition, checked the magneto, replaced the spark plug with one that looked right, but the electrodes got crushed because they protruded below the piston crown. Realized this, returned to the shop, was then advised it was probably the carby, so bought a carby kit which again looked right. Still no start, not a pop. Other you-tube videos advised the most likely remaining explanation was compression failure: the ring was quite loose with 0.5mm gap, so I found a replacement ring and fitted it (still some gap ~0.3mm, but that was all I could do). Still nothing, not a spark. Almost gave up, but for some reason decided to again watch the excellent explanations on this channel. Finally, thanks to this particular video, I went back into the carby and realized, just as he says at the 8:00 minute mark, the needle valve lever was set too high, causing continued flooding. Went back to the old lever, suddenly everything is great! Starts first time, every time, all the new parts have paid off, but I think it was all down to flooding and my failure to realize it. To their credit, the place that sold me the wrong plug and dud carby kit did give me some good advice about carby diagnostics: take it off and see if it can fire without it. If its flooded, I learned, it can run for quite a while from the fuel that's pooled in the crank case.
Kudos above all to you, Repair Specialist!

[puzoniasty]

That is perfect explanation what could be possible reason for 2 stroke engine malfunction. I spent a lot of time watching tons of videos about the problem and none of them was so clear and taking to the point as this is. Now I know what exactly I should pay attention to repairing the engine. Thank you Craig!

[bryanwhite]

Thank you ever so much. My "new" secondhand Stihl KM85R arrived not working. Following your instruction I was able to get it working. My very first engine that I've successfully fixed. :)

[extrasc]

Thanks very much for producing these very useful videos. I use Walbro and other similar carbs in my R/C airplanes. I have a 30cc engine that has been been out of service for several years. It now refuses to run. After watching your vids, I’m fairly confident I’ll find problems with diaphragms in both the fuel pump and metering systems. Carb repair kit is on the way. Thanks again.

[brainfeed]

Hi again like the comment below your video`s really inspire me to get all my none running brushcutters and strimmers going again, I was always a struggling student at school and always told to just go to sleep or just look at the book if you don`t understand.I never learnt much at school only read and write and low level manths, But pretty good at maths now in my head never used a calculator.I found out later in life I had a reasoning problem, This meant the way I read or got told how to work out things needed to be explained in a slightly different way or break things down more than it would need to.Any ways I have no issues in the way you come across explaining I understand perfectly, You understand when teaching people that they literally don`t have a clue to begin with` this way you can learn the ones who really don`t have a clue`and this is how teachers should be teaching pupils, I truly believe to learn someone they have to take things back to there basics and never assume people have a general understanding to start with as this will leave many pupils behind scratching there heads.I don`t know your back ground but if you were a teacher at college then you would not have many scratching there heads.thank you again.

[DueceBigelow]

best small engine carb video series I've found! Brilliant and thank you.

[Vfh........y]

Easily the best video I've ever seen on two stroke carburetors on operation and performance. Good show. SIR

[alryley]

Amazing video. I really appreciate the time and attention to detail you put into this

[untildenmyfren]

Best & most detailed Carb explanation video thus far!

[kookooglue]

Amazing video, never had anyone explain the possibilities that cause flooding so well, nor how the carburettor works.

[JArtMiller]

Another very well presentation using very organized thoughts and visual aids... Great job.