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MS-4SPA atomizer??

Jvon811

Well Known Member
I'm looking to do the modification to my MS-4SPA 10-5009 and change the nozzle to the atomizer and make it a 10-5009N. From research I've found (mostly on this site), it will alleviate my "Grumman Stumble" problem that I'm glad to hear isn't just my airplane.

I'm looking for info specifically on this modification and/or shops that will do this. Other than starting to cold call local engine shops, I thought I'd start here.

Is there a parts kit available from somewhere that I can do this myself? If not, is there a particular shop that is known for working on these carbs?
 
Martin inductions

Here's one option:
http://www.martininduction.com

Call Gene and tell him what your issue is and what you'd like to do. He is very knowledgeable especially about amateur built aircraft inductions. He is a great guy.

Hope this helps,

Joe
 
Try aerosport power they may give you a list of parts. There are a couple gaskets and lock washers with tabs that need replacing once you pull the carb apart. One of the gaskets is a tiny gasket on the end of the nozzle, when you remove the old nozzle you might not even notice its on there but make sure to install new one on new nozzle. It?s relatively easy to do but pay attention taking apart and reassembling so the internal parts and floats are seated correctly going back together. Perhaps a one hour job but very unforgiving to human error.
 
That's exactly what I was looking for! Thank you all for the input. Now I just need to call CubCrafters and see when it will be back in stock...
 
That's exactly what I was looking for! Thank you all for the input. Now I just need to call CubCrafters and see when it will be back in stock...

I believe that setup is for the CC340 but that is a good picture of the parts you will need. The hole in that nozzle is quite a bit larger than my stock 0-320 nozzle, i tried it and it ran kind of rough, presumably too rich, so i changed back. By the way, the stock nozzle in my ma4spa from aerosport is an atomizing nozzle with all the holes on the side. There are various sizes of atomizing nozzles. When i say sizes i mean primarily the inside diameter, which controls fuel flow.
 
So has anyone done the -4SPA 10-5009 conversion to -5009"N" on and O-320? That's all I'm looking to do.
 
The "pepperbox" atomizer nozzle doesn't help all that much in a new ECI Titan O-340 on my RV9A. Mixture distribution is still abysmal.
 
Don, The link you provided takes me to a conversion kit Part # 666-862-F. I did send an email and heard back from MS Carbs and I was given the Lycoming Service Instruction 1305C which calls for conversion kit Part # 666-813-F.

Is there a reason you used the -862 over the -813? Is there a difference?

Any MS Carb guru's out there? Mine is currently MS-4SPA 10-5009 mounted on a O-320-E3D (experimental now with higher compression pistons to 160HP).
 
I answered my own question for anyone following along at home...

The 666-813--F Conversion Kit is for the MS-4SPA 10-5009 converting it to a -5009N. Kit includes Power Jet Gasket, Nozzle Gasket, Nozzle Assembly, Throttle Body Gasket, and 4 nuts.

There is a Lycoming Service Instruction 1305c about the conversion (Which I would hyperlink but I can't seem to find it on the Lycoming website. I have a .pdf of the SI that I can send anyone needing it. If you email me for it, please remind me the file name is 1305c.pdf)

The 666-862--F Conversion Kit is part of a CubCrafters STC and is for a different Carb number, not the 10-5009. Weather it works or not for you, is up to you. I'm just relating what I was told via a phone call directly to MS Carbs.
 
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