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What carburator do I need ?

T

trackdom

Well Known Member
Before sinking in a deep depression I try a very last question....
What is The CARBURATOR for a O-320 D2A Avco lycoming for a RV8?
Any body flying safely a Rv8 with that engine would be my saver just telling me the PN of his carburator...
The very last issue before flying....
great thanks
 
Carb

Not sure the correct or best answer is the Manufacturer. It is a good place to start for sure. Hopefully, this is why Trackdom is asking the question.

I think the question should be: What carb flows the correct amount of fuel to the 0-320-D2A installed in a RV-8 and turning a C/S prop for a airplane based at a sea level airport on a hot day.

Correct amount of fuel would be the amount required to properly cool the engine during a Vx takeoff (Best Angle). Vx is where you ask for all the power with the least amount of forward motion for air cooling the engine. Therefore the fuel is required to keep temps under control.

Lots of RV's are running carbs that don't meet this criteria, but get by accepting hot temps, or limiting climb angles, or have FP props so they can't make 100% power on Take Off or live at higher altitudes etc.

Lots of us have drilled main jets and or installed "kits" on our carbs to get Fuel Flow up to where it should be. Because we did not have the proper carb.

If I recall correctly, Van use to sell the 0-360 A1A with the 10-3878 carb, but enough people complained or informed them that this carb was too lean, that they switched to the 10-4164 which is a richer carb.

On Certified airframes the manufacturer figures all this out with the carb manufactures and that is why we have several different carbs for the same engine. The list linked to tells us what carb "fits" the particular engine and obviously operates in some airframe.

This is why Trackdoms question is a good one! Now, he can buy the proper carb for his application instead of just getting one that fits and living with it or having to modify it.

Sorry for the long post but once I started it was hard to stop! Good Luck.
 
Thanks Bob for your response, that's exactly my meaning, find the person who flies a Rv8 with a O-320 D2A engine...
The same plane, the same engine...so the same carburator ....that should work!
 
What Carburetor do I need?

My 0320 D2A came out of a PA28-140 and it has a 10-5135 carburetor on it and i am happy with it's performance. It's in a RV7 with a Catto Propeller 70 x 66 pitch but Craig repitched. Also has EFII ignition. I can get about 3050 RPM out of it.

Keith Rhea
RV7
127 Hours
 
AK4x4 said:
Per Carb manufacturer; http://msacarbs.com/technical-data/engine-eligibility.html MA-4SPA 10-3678-32. Hope this helps, Russ
Click to expand...

The 3678 comes in two different versions, the -12 and the -32. One is a bit richer than the other, but the key difference in the outlet throat diameter. One is larger than the other. One is made for the straight riser sump and the other is for the other one (forget the name now). I went through the same research. There is lots of good information out there, just do some searching. Some of later model 4SPA variants have economizer circuits, but those really don't add much benefit if you have have complete EGT coverage and proper leaning skills.

I have a 5135 carb from a D series engine that I bought but never used. It was running well when it came off an engine at TBO. It needs a rebuid, but is quite servicable. I have been meaning to post it for sale, but never got around to it.

Larry
 
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I have just received today an overhauled 10-3678-32 carburetor. I am quite sure that will solve my problem. I am convinced my former 10-5217 carburetor didn't get the right needle?
this week end I run the engine, and let you know the result .
 
I have been flying with the new carburator for about 10 monthes, And I have no issue.
The fact is I run extremly rich , And I have to lean a lot not to foul sparks plugs.
After start up I pull the mixture at mid position , I don't take-off full rich , Cruising I lean a lot, one inch from the iddle mixture position, strange in fact, but it works, average egt 750 ?C CHT 160 ?C , max 180 ?C on take off.
Probably during the annual, I'll try again the former carburator with a larger needle.
 
With the original carburator, I was unable to push the throttle cause It was too lean , so I thought needle was too narrow. With the second carburator It runs too rich . I ? d like to reinstall the former one with needle a little bigger in diameter.
I can't tell what are P/N for these items .
I have no fuel flow neither fuel gauge ( I admit I gave up concerning these gauges...)
 
parts

Dominique,
I could see you taking both carbs apart and measuring both main jets.
You would know which one was lean and which one is rich.
Then you could drill the lean one half way....
 
Bob,
I know which one is rich and which one is lean, just looking at them . The best would be to enlarge the leanest one...
 
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