RE: DA-100 Needle Question
 

H Beam connecting rod. Very nice.:D Looks like it runs good too.

RE: DA-100 Needle Question
 

There is no carbon below the ring. In fact there was no carbon on or behind the ring groove.


I took cylinder pics too, but they didnt turn out to well. There was a small amount of carbon on the dome, but no different than the piston. No scoring on the piston or cylinder. Looks very good. From everyones opinion, it shouldnt look this good while running Amsoil 100:1. I spent alot of time hovering and 3D. Not easy for an engine.

RE: DA-100 Needle Question
 

The only thing Marvel does is reduce the viscousity of the oil used as the primary pre mix. Since it's being mixed with gas there's likely no change in anything, imo.

No, it's not normal to have carbon below the rings. I suppose all that black stuff is what the piston was originally painted with? Naw, they don't do that. I have 500 hour engines that have zero carbon below the rings. It illustrates the weaker ring seal using a 100-1 oil mix. The carbon on top of the piston also indicates the loads the engine is operating under. Not very much in this case. What was the supplied oil? I'm thinking it had a name.

The only thing hard on an engine in hovering and 3d is poor cooling. The engine doen't work hard at all. Hard on an engine is when one is flying a plane with a 0.2 to 1 power to weight ratio. Flying a plane with a 0.75 to 1 or greater power to weight ratio and the engine is loafing most of the time.

RE: DA-100 Needle Question
 

I guess the hovering\3D stuff only gets the engine as hot as it will ever get when FLYING. Your right, comparatively speaking it is easy for an engine to handle the effort. The oil supplied with the engine was blue and was not labeled. Could have been washer fluid for all I know. It didnt taste like it though. The discoloration on the piston is unburned fuel mixture being pushed by the ring under the compression stroke. It is not burnt. The ring seals the fire to get there. It is not carbon. Carbon comes from burned fuel. We all know that carbon is a by product of fire. I see it as extra lubrication for the bottom end. It is not caused by the 100:1 mix, as stated earlier, a pipe can cause it. :D

RE: DA-100 Needle Question
 

Gotta go with you on that one. Your engine is doing well, but I don't care for the blow by. That's power lost even with a pipe.

RE: DA-100 Needle Question
 

I was wondering about cross hatch. Worthwhile? I know the ring is good. But crosshatch and a new ring?

RE: DA-100 Needle Question
 

My experience has been that if you remove any varnish accumulations on the cylinder walls you can install a new ring and all is good. A brass rotary brush and kerosene does nicely. The cylinder plating is likely only about .002 to .004" thick and a little too much clean up bore ruins a cylinder.

Before doing that would you try an experiment that's a lot easier? For 1 gallon of gas, mix it up at 50-1, pick a good oil other than the Amsoil, and run the full gallon. It takes close to an hour of running time for any change in oil or ratio to make it to the top of an engine so a gallon is close to the minimum experiment amount. Fly the engine and do another tear down and tell us what you see.

The extra oil improves the ring seal and may well take care of the blow by situation.

RE: DA-100 Needle Question
 

I am game for an experiment, but it started snowing here today[:'(]. Flying season is near over and wont get a chance to run another gallon this year. If we get an "indian summer" I will try it. Gonna have to take the cylinder off again and try cleaning the black off the piston, around the ring. I have a feeling that it is permantly stained though. I will try cleaning it with Toluene.
I do have Dominator 50:1 Amsoil. Try that?

RE: DA-100 Needle Question
 

Just to humor me, don't clean the piston yet. Use a small bottle of Pennzoil Air Cooled, or better still, see if you can find some Stihl Ultra. See what that piston looks like after using the Stihl. Sounds like you might have some time on your hands;)

RE: DA-100 Needle Question
 

I've enjoyed reading this thread. Here is a tidbit regarding Pennzoil. For a bit over 3 years, I used BelRay MC-1 (I believe that is the correct number .... I know it wasn't H1R) in my gasser fleet and was very pleased with it. But this year, I decided to reduce my oil expenses and switched to Pennzoil at 40:1. I could buy it at the local auto parts store rather than having to drive across town ... and the cost is less than half of what the BelRay was. After a full season of use in several engines I have to say that every engine ran better this year than ever before. Last year after running the BelRay at 50:1, there was quite a bit of carbon on top of the piston in my DA-50 and some dark blow-by staining on the piston skirt. Everything looked excellent otherwise and I didn't remove any carbon. This week and a whole season later, I removed the muffler from the DA-50 to have a look inside. Most of the carbon on the piston top has gone away and there is clean alumimum showing on a good portion of the dome. The piston skirt is now cleaner and still shows no signs of skuff or wear. I'm not going to take the engine apart further so I don't know the condition of such things as piston pins and crank pins but I suspect all is well there too. Summary .... can't see any real reason to run anything other than the Pennzoil right now. As a side note .... there is almost no oily exhaust residue on any of my airplanes with the Pennzoil where there was just a bit with the BelRay. The mufflers are showing very little carbon residue also.

Guess I can't understand why anyone would want to run that expensive Amsoil stuff at any ratio when a low cost product like Pennzoil seems to be superior. YMMV

RE: DA-100 Needle Question
 

I know, I'm starting to think the same. RCbugman runs it and he works his engines at his job more than any of us. Plus he did a lot of oil tests. Makes me think he's onto something. [8D]

RE: DA-100 Needle Question
 

I switched to 50:1 Pennzoil last year and cant see a reason to go back.

RE: DA-100 Needle Question
 

That was the reason I asked that octanehuffer didn't clean the piston. I knew what was going to happen with the Stihl. Pennzoil does it as well. Either of those two oils are superior to many other oils, and both work equally well for our applications. I figured if I didn't let on that I knew how it would work out I could talk him into the experiment. I also knew that one he tried it, he would very likely stay with the different oil;)

Seen the end results far too many times to think there could be any doubt.

RE: DA-100 Needle Question
 

Yeah I went to price some Stihl oil at a hardware store that's a big Stihl dealer. Sooo expensive. Even the 100% mineral oil was like 4 times more than Pennz. I'll go with Pennz for 1.88 per 8 oz bottle thanks. In fact it would be a hoot if the Stihl was nothing but Pennz in a differnt bottle for 4 times more....:)

RE: DA-100 Needle Question
 

It's definately not the same. The Stihl Ultra is full synthetic.

RE: DA-100 Needle Question
 

Even the regular Stihl was expensive. Way more than I'd pay.

RE: DA-100 Needle Question
 

Happens with their chain saws too;)

RE: DA-100 Needle Question
 

Good posts here. I am starting to believe that the problem here isnt, that the BRAND is at fault, but that the mixture is to blame. I would believe that the more oil there is the greater the life of the engine. Using 100:1, the oiling capablity is proper for lubrication of the metal to metal parts- it just dosnt burn well. As evedint of all the carbon. Itsa getting completly burned above the piston and cusing carbon. An incorrect length header can aggrivate this, by not scavenging properly. Wouldnt most any oil make the same differnce at 40:1. Granted, Penzoil, Stihl, Lawnboy, etc all have differnt detergents and additives blended, but the cleaner burn should still happen with any oil. True?
I am not trying to uphold any certatin brand here, just getting the facts straight.
Adam

RE: DA-100 Needle Question
 

I think RCBugman used different ratios in his test. Anybody remember or have a link? After reading his test, I switch to Penzoil mixed at 40:1. I'm running this in my ZDZ 120, G38, Lawnboy Mower, Homelite weedie, Snow Blower, Leaf Blower, and will be firing up my used/new to me, ZDZ 160 today with the same mix. Early this year I took the ZDZ 120 off one plane to put on another. I couldn't believe how clean the piston tops were. Hardly any blowby either. An 8oz bottle of Pensoil is $1.29 at Farm and Fleet and I dump the whole thing into a 2 1/2 gallon can. I fill my plane can up from that can. Always fresh that way.

RE: DA-100 Needle Question
 

It's not just the mix ratio, it's also the type of oil and the additives blended in. Racing oils do not always have much in the line of detergents because racers do a lot of internal engine work and generally clean up their stuff when inside. Oil flash points and the temperatures they beging to varnish has an impact, along with a bunch of other factors.

One thing I know without any doubt, with the exception of a couple of oils, all of them performed better with more rather than less. The exceptions had deficiencies at any mix ratio.

That's as far as I go with that direction of discussion.

RE: DA-100 Needle Question
 

Adam,

Several of my engines came to me used from a very good friend that used a popular mineral oil from a company that makes green lawn mowers. All of these engines looked extremely good inside .... minimum carbon, good appearing piston skirts, etc. But all of the mufflers and exhaust ports showed extreme amounts of carbon build up. Now I knew the history of all these engines and had flown them extensively for many gallons of fuel. They were always properly tuned so I knew that wasn't the problem so the only cause of the heavy exhaust carbon had to be the oil used. I switched these engines over to the BelRay MC1 for several seasons and the exhaust carbon problem went away .. but I saw increased amounts of piston dome carbon buildup and some staining (no additional wear) on the piston skirts. This year, after switching to Pennzoil, I see greatly reduced piston carbon buildups and no additional exhaust port / muffler carbon buildup. Seems like a win - win situation to me. I believe that Pennzoil does burn in the combustion process unlike some synthetics so there is very little residue coming out exhaust pipes, which is a big reason why some people choose to use the 100:1 oils ... strictly cosmetic! I chose 40:1 for the Pennzoil strictly because I already had a mixing cup graduated for that ratio .... errrr, I'm lazy and it is easy to mix at that ratio.

So I'm using Pennzoil now because it is cheap, it works well for me in my strictly unscientific tests and because I'm a bit lazy, it is easy to mix with an existing measuring cup.

Regarding the Stihl oils ... I have used the Stihl regular (non synthetic) oils at 50:1 in my saws for years and out of the bottle they have a higher viscosity than the Pennzoil. I know nothing else about them other than they do perform pretty much the same as Pennzoil as far as keeping the engine clean and carbon free. I now run my saws on Pennzoil at 40:1 and they required no needle changes for the mix change. I had considered Stihl oil for my airplane engines but chose Pennzoil strictly because of price.

RE: DA-100 Needle Question
 

Why move away from what works? Especially when the price is good.

RE: DA-100 Needle Question
 

I know I am going to be crucified for this but, one of the reassons I like the thinner oil is less cleanup. Hell hardly any. I fly literally everytime it is nice out and the stated time on the engine in the pictures, was brand new as of last spring. Thats alot of flying in 2 seasons here! I am able to pack the plane away and huck it before and after work. It usually stayed in my car all summer long. I clean it maybe once a month. With the other planes, I did notice a large power increase when I did switch to 100:1. I did HAVE to try the Dominator once before an IMAC competetion(inconviently ran out of oil and had no time to drive and find 100:1). Runing at 50:1 the day before I had to drive to Chicago for the meet, the plane had poor throttle and a very bad transition. Even when i had tuned it. Great, I thought, the plane runs terribly and I have to drive to Chicago like this after work tommorrow. Luckily, I called a good friend, and he gave me a quart of the 100:1 before I left. Mixed a new batch of gas when I got to the field and started exactly like before I switched to 50:1. Good power again. I had large slobber snot chunks on the bottom of the plane that would smear if I tried cleaning it. I dont want that. And its obviuos that the 100:1 does a proper job lubricating the components, it just dosnt burn that well. Something, anyone can live with. So be it if I have to clean the piston off once every 200 hours. It only takes .5 hours. Does the Stihl or Bel ray pass out snot?
i really want to try the oil/mixture testing guys, but the season is over. I still have 3 props to test, but I want to make long consistent studys of the oil. Something this year wont allow. Hell, I doubt that there is even 8 total hours left of flying up here.
So the oils I need are:
BelRay(wich one)
Stihl Ultra
Penzoil

RE: DA-100 Needle Question
 

I have very little oil residue on my planes when using Pennzoil. I believe that most of it is burned in the combustion process. When using BelRay MC1, I did have just a bit but certainly nothing I would call the "snots"!

RE: DA-100 Needle Question
 

No worries Octanehuffer, just enjoy the flying time you can get;)