2-Stroke Carburetor Diaphragms Different Colours. This is why!

CHAINSAW CARBURETOR DIAPHRAGM: Different Colors Explained!

The video you mentioned highlights an important aspect of 2-stroke carburetor maintenance, specifically the different types of diaphragms used in these carburetors and how they can affect the performance of chainsaws and other 2-stroke engines. Let's delve deeper into the topic:

Rubberized Carburetor Diaphragm (Black):

Structure and Function: This diaphragm is black and known for its flexibility. It is highly efficient at pumping gasoline fuel through the carburetor.
Ethanol Sensitivity: Vulnerable to ethanol in gasoline, so it may degrade quickly when exposed to fuel with high ethanol content.
Mix Handling: Suitable for heavier fuel-to-oil mixes, like 20:1, due to its ability to move viscous mixtures.
Storage Sensitivity: Prone to deterioration if left unused for extended periods.
Acetate Carburetor Diaphragm (Various Colors):

Structure and Function: These diaphragms are available in various colors (e.g., black, blue, green) and have a shiny plastic appearance.
Cold Climate Usage: Believed to perform better in colder climates but may require more carburetor adjustments for optimal performance.
Pumping Efficiency: Less efficient at pumping gasoline fuel through the carburetor due to their harder, less flexible material.
Recommended Mix: Works better with weaker, less viscous 2-stroke oil to fuel mixtures, such as 50:1.
Ethanol Resistance: Excellent resistance to ethanol in gasoline and offers good durability.
Teflon Carburetor Diaphragm (Teflon Fiber/Glass):

Structure and Function: Made from Teflon fibers or fiberglass, these diaphragms are more flexible than Acetate diaphragms but slightly less flexible than Rubberized ones.
Pumping Efficiency: Offers a better flow volume through the carburetor compared to Acetate diaphragms.
Ethanol Resistance: Resistant to ethanol in fuel and capable of pumping heavy fuel mixes.
Quality Considerations: Diaphragm quality can vary; high-quality Teflon diaphragms tend to perform better and last longer.
Overall, the choice of diaphragm type depends on factors like the specific 2-stroke engine, the fuel-to-oil mix used, and the operating conditions. Chainsaw owners and technicians need to consider these factors when selecting the appropriate diaphragm for their carburetors. Additionally, it's important to note that the quality of aftermarket diaphragms may differ from those of well-known brands like Walbro, which can impact performance and durability.

Proper diaphragm selection and maintenance are essential to ensure that 2-stroke engines, including chainsaws, operate efficiently and reliably. Regular inspection, cleaning, and replacement of diaphragms, as needed, are crucial steps in maintaining the performance and longevity of these engines. It's important to consult the manufacturer's recommendations for your specific equipment and to follow best practices for carburetor maintenance to ensure safe and reliable operation.

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Thank you for watching and I hope you gain something from this video.

Craig ( Owner and Creator of The Repair Specialist Channel)

#2StrokeCarburetorMaintenance
#DiaphragmTypes
#ChainsawPerformance
#EngineEfficiency
#CarburetorDiaphragms
#FuelMixRatio
#EthanolResistance
#ChainsawMaintenance
#CarburetorCare
#TeflonDiaphragm
#AcetateDiaphragm
#RubberizedDiaphragm
#EngineProtection
#FuelEfficiency
#CarburetorAdjustments
#FuelSystemCleaning
#EngineDurability
#2StrokeEngines
#ChainsawTips
#ProperMaintenance

[garymcmullin]

I had no clue about material differences. I have noted "extra" diaphragms but never gave thought to why they were there. Best I can recall there is no labeling on the kit packages to help a mechanic understand choices in material or that there is even a "choice". You are such an excellent teacher on these small engine subjects, thank you for upgrading our knowledge base!

[georgecolbert]

I too have used the rubber types for years, but now are seeing the plastic and Teflon ones in the kits. Thanks for explaining the differences.

[Willy]

Thanks for the heads up. I have always wondered why there were different diaphragms in the repair kits.

[jamesmordovancey]

Thanks, from the U.S.A., where despite all my years working on carbs I never knew about the colors. I just replaced with the same type material.

[RaleysSmallEngines]

Ecellent explanation !! I always wondered about that, now I know, thanks to your great video.

[GuysPlayingWithTools]

I try to match up diaphragms with the one that comes out every time. So far it's worked out pretty well. I agree 100% about the ethanol issues, if I were honest, ethanol side effects supply probably 70% of the "broken" used equipment I buy

[aaronpowell]

I've also heard the teflon type have higher ethanol resistance and gladly install them in carburetors for other people, as ethanol laden fuel is everywhere in my area. For my personal equipment, I typically prefer the rubber type as I do not use fuel with ethanol in it and I assumed the rubber diaphragms were more accurate and better sealing. The last few strimmer carb kits only included the acetate style and I've had no issues using them either.
Thanks for sharing👍🏻 your explanations make perfect sense to me!

[adnacraigo]

Excellent instructional video. Thank you Craig for helping me understand. I have wondered this many times.

[ericvaughn]

Thanks for the info on this one, Craig. I don't think I've ever seen a rubber pump diaphragm in a machine or in a rebuild kit (Walbro, Zama or knockoff). I've seen and used plenty of acetate though and I think I've tried a teflon diaphragm a time or two without noticing any difference or different tuning required. Experience from blowers, weed eaters and chainsaws in the Southern US here.

[spelunkerd]

More to think about, thank you. I'm surprised that any gaskets or diaphragms made today are still vulnerable to ethanol damage. Ethanol is even present in fuel stabilizer, so it is hard to avoid.

[justharryjohnson]

Thank you for this video. I went with the Teflon on my last rebuild and it has already lasted longer than the rubber one.
Thanks again

[KensSmallEngineRepair]

Great Info Craig! We have Ethanol here and I see more of the plastic (acetate) and Teflon diaphragms used in my area (NE USA). If I have the choice I prefer the Teflon type. I buy 90% OEM Walbro or ZAMA diaphragms. Knowledge Is Power!

[tyroneclarke]

Great video mate. Thank you for sharing your knowledge. Cheers

[arthurfricchione]

Craig this is the first time I’ve ever seen this issue addressed. I always purchase from Briggs and Stratton and never come across this here in the states . Always the black rubberized. Thanks for sharing good info👍

[HobbyMotorDK]

Fantastic information - thank you very much for sharing this.

[petertothpete]

Excellent explanation of diaphragm types! I knew there were different ones, but didn't pay a lot of attention to what they were made of, just matching what the carburetor came with. Ethanol is not only a killer of diaphragms, but the entire fuel system as well. Even Tygon line succumbs to it. The metal of the carburetor gets eaten by it as it's a magnet for moisture. I'm fortunate to have ethanol free fuel available and highly recommend it to all my customers.

[MDmathews]

Did not have that information prior to this. But I have a chainsaw that has been old faithful. I live in the southeast. It has recently gotten colder than it has been. The saw has a rubber diaphragm on it. Well the carb is clean. It will not run properly. Weed eater, mowers ect run fine. Non ethanol fuel. Changed diaphragm saw runs great. Thanks!

[erozC]

Great information. The OEM Zama EL41A kit came with a transparent diaphragm to replace the black one. I wonder why. Also, contemplating the benefits of using alkylate premix fuel or RON98E5 mixing myself and how that plays out to the big picture. Thanks for the educational videos!

[Indeewoods]

What I think is that your videos are awesome lol.
To give an example I used to be a Johnsered chainsaw dealer and I purchased a saw as well as a trimmer back then and that was around 2002.
I’ve never had any problems with the carburetter on my trimmer, and it has never ever seen ethanol fuel, and I decided to pull it apart to clean it two years ago, and I was astonished that it looked like a completely brand new carb there was no dirt or no anything in that Carb.
I pulled others apart that I started using ethanol after only one year and I was seeing a white powder inside of them even just a Lake coding. It just eats everything.
I’ve used ethanol fuel, and it takes out the check valves as well. Best to just not use it at all, if you can.
In Canada here we have a few fuels that have no ethanol in them .

[ryanbruner]

Wow, great info, I never thought about this!