DA-100 Needle Question
 

Hey,

Getting ready to switch over to 100:1 Amsoil on my DA-100 and right now its running awsome on the 32:1 Lawn Boy with the current needle settings. I know when I make the switch to 100:1 I will need to tweak the needles to account for the change, will I need to richen them, or go the other way?

RE: DA-100 Needle Question
 

so you want to switch from proper lubrication to just so-so??
Think twice. An engine needs oil to operate well. I suggest you use any 1:50 brands quality oils instead. Slippery engines run a lot better.

RE: DA-100 Needle Question
 

[sm=lol.gif]

RE: DA-100 Needle Question
 

Pe,

I had originally started a post in this one that would have been quite a bit ahead of yours but deleted it because I wasn't going to be the one to start it;) I'm very happy to see my restraint rewarded with someone else doing it for me:):D

RE: DA-100 Needle Question
 

Guys, I asked a simple question, and really one that I didn't need to ask, as I can tune the engine. I was just trying to get a feel from others who have DA's, what their experiences have been. I typicaly fly jets and heli's and don't have to worry with this, oil in jets either runs or it blows up, no extra performance when trying different ratios, DA even recommends Amsoil 100:1.

Im a gear head, you can opt to run your engines 32:1, 50:1, etc thats your choice but I have ran about 7 gallons thru this puppy at 32:1 and now im ready to make her sing, let her breath and get those few extra rpms. Now if this were in a warbird or a scale machine I probably wouldn't worry but owell' its not, so get your slow crap "outta da' way"[sm=lol.gif]

RE: DA-100 Needle Question
 

Pe, T.O.M, and Mr Bigg, ya know what we need? Lots of volunteers, willing to post oil, ratio, gallons or hours burned, picture of the installation/baffling...and the kicker, pictures of the piston top, bottom, skirt, ring and groove, along with the plug and its age/hours burned. This would only be useful if there were enough posters to get a good variance of hours on engines with their respective setups. Not for the sake of argument, just pure data collection, and a place where people can form their own opinion based on a little more proof, rather than hearsay.

Who am I kidding, we'd prolly argue a little :) However, I think if enough people were willing to be that 'forward' with their personal results, more would learn up front the affects of these choices, long term on their shiny investments. I wonder how many people have such strong oil and ratio suggestions, that have never even seen the affects on the inside...hmmm

I know I know, I nearly passed out for a minute there...the oil war has gone on forever, and probably always will, forget I said anything :eek:

RE: DA-100 Needle Question
 

Hmm I think while im at it, I might aswell just prop it down. Oh' I dunno say a 25x10, maybe I could hit 10,000 R's....... Not too mention running on some Turbo Blue.... Smellin' and Soundin' Good :D

I'll be glad to post a picture up when I get a fist sized hole knocked in the case if you want?

RE: DA-100 Needle Question
 

Another internet forum MYTH...You 100-1 Amsoil people are all the same...Less oil = LESS performance, not more...We raced at El Mirage dry lake last weekend....One of the fastest unlimited planes is a modified P51 running a mostly STOCK DA 170...It DOES turn 10,000 rpm...It DOES NOT run 100-1 Amsoil...Race pilots want ALL the performance they can get...A race pilot would not even THINK about 100-1 Amsoil in his 10,000 to 12,000 rpm race engine ...PERIOD...
We run a 289 twin, use 8% oil...We LIKE the long black streaks down the fuse from the extra oil...
You think hovering around for a few minutes puts a load on the engine ??? NOTHING loads an engine like running WOT and turning a 180 degree turn at the end of a 1600 foot straightaway...
If 100-1 would increase performance, everyone would use it...NO ONE does, we KNOW better...
And have tried every imaginable oil and fuel mix possible in the last 20 years of racing...
LOTS of oil works best....

RE: DA-100 Needle Question
 

Amsoil at 100:1.

RE: DA-100 Needle Question
 

:D

RE: DA-100 Needle Question
 

Too bad that picture did not have a bit more clarity, but it appears to contain some of the symptoms I've seen in many other 80 and 100-1 engines. The difference is the depicted engine has not achieved much running time yet so those symptoms are not as yet well pronounced. I measure engine life cycles and wear in hours, not gallons, and if it won't make 400 hours or better it's not worth using.

Regarding the needle positions. Both will change significantly and both will likely be in opposite directions. Leaner on the top end with the new ratio. You did yourself no favors using the Lawnboy and may have already started a down hill process that will be accellerated with the change to a lean oil ratio.

As for hours of running, photos, testings, etc. Since I work for a privately funded organization I can't publically share IP developed on company time. My job would dissapear in a heatbeat. I've already had one hobby product manufacturer mount an attack against me in this manner. However, I can, and do, use the results obtained at work for the operation of my own engines, used for personal pleasure only, on personal time, and have found that continued use of those methods provides better engine performance and greater engine life cycles. In short, 100-1 is not the way to go with any brand of oil. A lightly loaded engine can get away with lean oil ratios for fairly long periods of time but it will eventually pay the price. A heavily loaded engine will not last long at all at lean ratios. Too many thousands of hours of engine time have proven that to a level where the percentage of doubt is zero. I have lot's of pictures from lot's of engines but I can't post any of them.

Elson is in a somewhat looser situation since some of his work may be funded with public dollars in a non restricted category. From my perspective there is no room for debate on the ratio issue since all the debate was eliminated during actual operation of numerous engines over extremely long periods of time. The rest of you folks can have at it based upon the extremely limited amount of running time your engines have accumulated.

RE: DA-100 Needle Question
 

T.O.M.....fully aware and respectful of your situation, I was actually referring to the folks that adamantly chant 'amsoil 80:1 or amsoil 100:1' and wishing they would open up their shiny engines and give us all a peek after some significant run time. I know that yourself, Elson, Ralph, Pe and others have fully tested this and know the outcome, from years of experience actually testing, with disassembly and inspection to acknowledge results. Though I have seen it happen time and time again on the forums, the 80:1 or 100:1 crowd almost understands and agrees, then poof, they're gone and chanting again. There certainly is dedication there, or someone incredibly influencial at the beginning of that deal. In the meantime I'm going to keep spitting a little 40:1 of a better oil on my airframes.

RE: DA-100 Needle Question
 

Skymac, here is the answer. You are moving from 3% down to 1%, so a given volume of fuel will contain slightly more actual gasoline, hence the need for a slightly leaner mixture.

To tell the truth, there will be a large performance gain moving from Lawnboy to ANY good quality oil around 50:1 ratio, especially the good synthetics. There will be very little improvement between how a newer engine runs on 50:1 and on Amsoil at 100:1.

Obviously more gas per the intake charge can lead to more combustion power, but more oil => better ring seal => more efficient transfer of the combustion expansion forces into moving the piston and turning the crankshaft.

The added benefit of greater protection from friction-related damage is a bonus.

RE: DA-100 Needle Question
 

Some of the 80 to 100:1 crowd would not even be contemplating that ratio if DA did not recommend it. Anybody know the reason Desert Aircraft does? Do they have investment interest in Amsoil? I'm just curious. By the way, the pic I posted above came from an engine that was for sale. I could tell already what oil and what ratio he was running before I even asked.

RE: DA-100 Needle Question
 

and Belray H1R at 50:1, Redline @ 40:1, Mobil 2T @ 32:1, and...

RE: DA-100 Needle Question
 

I have nothing personal against DA at all....however, I will comment that this is one manufacturer that really tends to bend over backwards for their customers. I regularly hear about engines being de-carboned, repaired..etc, with no questions asked. I suppose in ways their customers are paying for that kind of service which is really outstanding. So although the 100:1 suggestion on their part might sneak by on low loaded, low time engines...on the ones that don't escape the inevitable, they are cleaned and/or repaired in many cases anyway.

It would take someone like DA, to stand up and not warranty such things as lubricants and lean ratios that promote such results in their engines, to potentially make a dent in the impact and get some to start paying attention.

RE: DA-100 Needle Question
 

The 100-1 crowd is greatly influenced by what manufacturers suggest I think. I'm not going to pontificate on reasons some choose certain oils and ratios. There are clearly different opinions, but I know that both Bel Ray MC-1 and Redline work very well at 50-1. The H1R is oil manufacturer limited to 40-1 and richer ratios

The fact that anyone de-carbons well before 100 operational hours should tell people a lot about their oil and/or their ratio. If it needs to be done before that you have something wrong and need to make a change. At 100 hours there should not be much carbon on the top of the piston or the combustion dome if the mixture was close to right, the cooling was pretty good, and the oil type and ratio was a good one. At 100 hours you might finally be starting to see a ring thinking about sticking very slightly at the exhaust port. Very, very slightly. Easy to clean and correct at that point should it happen. The piston skirt should look almost new with only a very small segment on the bottom of each skirt being a little smooth and shiny. There should be no scratches running vertically on the side of the piston and there should be no brown or black carbon staining the side of the piston below the piston ring. You should be able to repeat that cycle 6 to 10 times with any replacement parts limited to a piston ring and cylinder gasket at around 500 hours.

If you work with enough engines long enough you can pretty much tell how an engine was broken in, how hot it has been run, and what ratio within a small spread, and see a difference between someone using a synthetic and a mineral. So folks, when you send an engine back for a check up, believe that the manufacturer really can tell what you've been doing[8D] Kinda like Santa Claus, they know when you've been good or bad.....

RE: DA-100 Needle Question
 

great information,now if i can just remember it when the time comes.:D

RE: DA-100 Needle Question
 

Like Zippi would say..."It don,t look good"

RE: DA-100 Needle Question
 

Sure don't.

RE: DA-100 Needle Question
 

Here is mine from tonight. Evolution 45. First time I had the jug off. On its 3rd plug. Spins a PT 22x10 to 6900rpm. Never missed a beat. Runs very, very well.
You pros tell me how it looks.

RE: DA-100 Needle Question
 

Did you break that one in using an ashless type oil? Overall she looks good. Lots of black carbon blown by the ring all the way around, which was the reason for the ashless question. Almost zero carbon debris at the top of the crankcase so it's been hand cleaned or the piston black is old stuff. Don't know if the ring was disturbed from the groove during disassembly or if that was the natural tension when it came out. Carbon on top isn't bad, looks more of the soft variety from being a run cold or rich. OR, you're running a tuned pipe, which effects the blow by too;)

How much time do you put on a plug? They can go a hundred hours or so between changes if everything else is right.

RE: DA-100 Needle Question
 

I broke the engine in with the supplied oil for the first 2? gallons. After that it has been AMSOIL 100:1. I HAVE 200 HOURS ON THIS ENGINE. Timed by my transmitter. This is the first time I have had the jug off and the pics were taken just after. No cleaning or touching anything. It has run on a tuned pipe since day one. The ring is at its natural tension sitting in the piston. I cleaned the carbon off the piston and put it back together. Ready for more service. Doing some landing gear repair now and the engine was just sitting there, so I decided to take it apart for this thread.

RE: DA-100 Needle Question
 

Let's see the cylinder.

RE: DA-100 Needle Question
 

The potential problem will be the build up of carbon below the ring. It will do one or two things. Build itself thich enough to scrape the cylinder wall or if you get the engine hot enough it wiff fry, crumble, and scour the cylinder. It builds up two ways. From exhaust gasses passing the ring, and when the piston is hot, intake gasses and oils burn from contacting the piston below the ring and deposit there. I guess the top inside of the piston is as black as well.
It's normal for it to be there, unavoidable unless you put put around all day. The area shown in pic 4 has the most and I'd clean that. UL pilots are now using Marvel mystery oil to reduce carbon build up. I've just started using it with my Synthetic oil and a few gallons from now I'll be able to find if it is helping.