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Is the NGK DR8ES-L equivalent to the AutoLite 4163?

I looked yesterday and I am currently using the DR8ES, not the -L. the -L is just a half heat range indicator. I think it means it would then be a half step colder plug, because it is a 8.5 temp plug, but not as cold as a DR9ES.

Ok thanks for the reply Mike. When I searched for a NGK compatible plug to the Autolite 4163 the number I listed with the -L is what came up on multiple web sites.

I'm currently working on the due system. I noticed right away where the needle was currently set a good 1/16" away from the start of the needle taper.

So...per the aerovee instructions I've marked the start of the taper with a sharpie...and am watching the needle move as others mentioned when I'm tightening the set screw. No matter what I do it keeps moving in to a "leaner" setting as I tighten the set screw. Never noticed this before!

EDIT: I just tried Mike Smith's suggestion of firmly holding the needle inside the carb throats and that worked!

I seem to recall someone saying that they had inserted a steel ball bearing between the locking screw and the needle carrier that prevented the needle from moving. Sonex recommended distorting the threads on the needle carrier slightly to add friction (mash gently with a pair of pliers).

That's good to know Charlie. It's amazing how much the needle carrier moves as you tighten the set screw.

I wanted to report back that the engine is running a lot better now. This whole experience allowed me to drain the fuel tank and clean the strainer and shut off valve / fitting and fuel level probe and remove & reseal them with EZ Turn Fuel Lube. Did the same with the gascolator and fuel line connection at Aeroinjector.

I'll try the new spark plugs (NGK) this weekend...the UPS guy just delivered them from Amazon Aircraft Supply!

https://youtu.be/hVgVTg0GUbc

Just a quick update...I've now put another 2 hours and several flights on the engine since I resolved the tuning/ mixture issue! That was the problem. Got up this Morning and took a quick flight and video.

https://youtu.be/aE4DxG5KIs8

That's great news. Always nice for the problem to end up being something relatively simple. I suspect some of the negative opinions of the Aeroinjector are due to motion of the needle while tightening the set screw. As others mention, I also hold the needle while tightening, but I still have it slip a little and just retry a few times until I get it right. I personally haven't noticed a need to adjust for the seasons, so no more of these adjustments for me now.

Nice video. I always gotta ask people what propeller they're using. Is that the Sensenich 54x44? I noticed your radio was receiving for the entire video. Was it receiving actual transmissions or some kind of noise?

gammaxy wrote:Nice video. I always gotta ask people what propeller they're using. Is that the Sensenich 54x44? I noticed your radio was receiving for the entire video. Was it receiving actual transmissions or some kind of noise?

Chris:

Thanks, it was a quick video on my iPhone. Happy with the performance, I'm not going to mess with mixture anymore (for now :)

Propellor is a Prince P-Tip (Carbon Fiber) 54x44.

It was a nice morning and you probably noticed my frequency was 122.80, a very common CTAF for central Ohio. Others were in the pattern as I was leaving KMRT, and I was picking up radio calls for Port Clinton (along Lake Erie) and 2-3 other airports.

I wonder if the needle is the culprit or possibly the spark plugs in my plane. As I've been getting a feel for my new plane I have noticed that it runs a bit rough WOT once I get up to 5000. It seems to be solid at lower altitudes, but leaning the mixture didn't help anything once I got up a bit higher. I know that Don made a few changes with the needle size in the aeroinjector from his phase one notes and logs. It looks like he installed a 2.5 needle, then a #3 needle just a few hours later and made a bunch of adjustments with each needle option he tried. I definitely need to learn about the aeroinjector and how to tune it well to optimize the performance. That's one of the many things I hope to learn about by visiting the Sonex headquarters.

I've been running the #3 needle for the last 100 hours with good results. I did a lot of needle testing, even making four needles with varying dimensions. What I found is, there is a thickness of the taper, when it's located at the orifice opening, that gives you the best wot, and a different thickness that gives you the best idle. These two "sweet spots" have to be located within the travel of the slide. If they aren't, you have to make large mixture changes at idle to keep the engine running after landing. The #3 needle does this. I fly with the needle set 2 1/2 to 2 3/4 turns lean from "0", the beginning of the taper. Mark the bottom of the needle with a sharp file, the felt marker line is 1/2 turn wide. We're talking about 1/8 to /1/4 turn adjustments here. It's a 3/8 X 16 screw. One turn equals .060 movement. Remove any slop in the needle holder ball joint. Hold the needle while you tighten the locking screw. Accuracy counts. I make a slight mixture adjustment, about 1/4 inch, at takeoff to richen up a little to keep the temps in the green, and lean it back at cruise for economy. I make no mixture adjustment at idle, 1000 rpm, after landing and no seasonal adjustments. With the other two needles I had to do a run up before takeoff to guarantee max rpm and after landing move the mixture almost to cutoff to idle smooth. My experience may not be typical, but it couldn't be simpler.

FYI, I'm running the Sensinich 54 X 44 wood prop and I see static rpms in the high 2800's. When Bill Larson went turbo, he let me test his old Prince P tip. Same pitch and dia. I warmed the engine, did a wot run up with the wood prop, changed props and did the same with the P tip and saw an increase of 150 rpm static. The P tip obviously changes pitch under load. This is probably a plus on take off, lower pitch, higher rpm, but when I took a short flight, I couldn't quantify any change in cruise speed. The prop is supposed to return to the 44 pitch at lower loads in cruise flight. Not a very scientific test but the P tip seems to perform as advertised.