Insanemoondoggie

I run mainly 4 strokes Saito,ASP and Magnums and use only 15% Omega , which I buy 5 to 6 cases at a time. I,ve had nothing but good luck with Omega and was wondering if it well work well in the YS 4s engines. Been wanting to try one , but have held off because I,ve heard that they are picky with the type of fuel they use, or so I have gathered from the forums.
Is anyone running Omega in their YS engines ?

TFF

If you dont want trouble out of your engine get some 20/20. I run Omega 10% in everything else I have, but run 20/20 in the YS. The castor will make the pump stick within a week and you will complain that YS are junk but it will be the fuel. They also tune easer with the higher nitro; that is why many use the 30% heli fuel.

42etus

My Feedback: (2)

I wouldn't use any fuel that contains castor oil in my YS engines. It can gum up the regulator. The synthetic oils are fine lubricants and castor just isn't needed anymore. I don't mean to start a castor/synthetic debate, just stating the truth.
YS engines love nitro, they'll run on 10%, but they'll run stronger and be much easier to tune with more nitro. I run my YS's on Cool Power 30% without any problems at all. They'll idle 'till the tank is empty if I were to let them, and the throttle response is truly instant.
Paul

ChuckW

I run my YS's on Cool power 15% and they do just fine. A lot of people claim that the engines absolutely require higher nitro but it simply isn't true. If you know how to tune an engine, they will run fine on 15%. Now could you get a little more power by using higher nitro? Of course but I have so much of the 15% on hand for other stuff and I hate to pay more for fuel. Besides, even on the 15% the YS's make more power per given displacement than most other 4-strokes. I've owned or own the .63-FZS, .91AC and the 1.10FZ so I couldn't say for sure how the others do on 15%.

As for Castor, I just don't like it at all, especially in a 4-stroke since I've seen it lead to gumming up, stuck valves, etc. It probably will have an affect on the YS regulator if the engines sits for an extended period too but that's no big deal t clean or replace if needed. Still, if you are happy with the Omega, the YS will run well on it.

I also steered clear of these engines for a while because I heard they were difficult and watched others struggle with them. They are no big deal though. Just hook the fuel lines up per the instructions, tune and fly. It turns out that I had a lot of aprehension over nothing. You'll hear people say that you have to do this or that to them but I've found that if the basics are good, they don't require any special care beyond that.

The only thing I do not like about them is that they are slimy like a Saito but once you punch the throttle and see the power, a little oil on the plane is a small price to pay. With the right prop the acceleration is bascially instant, almost like a little top fuel engine and they'll idle all day sounding sorta like a little Harley v-twin. Definitely cool engines

MikeL

My Feedback: (3)

It depends on the engine. YS's documentation will generally list 15% nitro being a minimum, and oil requirements range from 15% to 24%. What you'll generally hear is that 20/20 synthetic is the preferred fuel. I played around with using 15% Cool Power in a .91AC, but it just didn't compare to using Wildcat 20/20 in the same engine. The 1.10FZ-S is supposedly more tolerant of 15%, but I haven't bothered to try it. I'm very happy with the results from 20/20.

Gray Beard

My Feedback: (-1)

I run a number of YS engines from the 1.10 to the 1.40, the only fuel I use is the 15% Power Master. I have tested fuels from 5% to 30 and the only thing I have ever noticed is the idle becomes rough on the 5%, I have never noticed any great power improvments with the higher nitro content, just easier to tune. A few more RPMs isn't worth the extra money to me. The Power Master fuel is a blended oil, they don't state what the castor blend is but most blends only contain 2 or 3 % castor. Mine ran fine on the Omega 15% when I used it. I buy my fuel when it comes up on sale so I'm not really stuck on one brand but the Power Master comes up on sale at Hobby People all the time. The one and only problems I have ever had with any YS engine is every once in a while I need to replace the diaphragm, no big deal, just two screws and off you go again.

MinnFlyer

My Feedback: (4)

I also use only Cool Power 15% and my YS 91 and 110 run great

Hughes500E

My Feedback: (16)

Power Master full synthetic 20/20 for me in YS engines and my Saito 3 cylinder!
Love it!

ChuckW

I tried the Wildcat 20/20 in one of my .63's. There was a couple hundred RPM difference in the top end but nothing to get excited over. It could have even been attributed to better weather that day for all I know. In the air there was no noticeable difference in performance. The plane was just a lot more gooey at the end of the day. Maybe that thicker oil was beneficial but I've never had an issue with Coolpower. I gave the remaining Wildcat away and switched back. I just couldn't justify the extra cost for my flying.

Gray Beard

My Feedback: (-1)

Chuck, when I see people stating that YS requires high nitro fuel it grates on me. I have tested from 5% to 30% and there is a slight difference in the rpm but nothing to jump for joy about. A couple of hundred rpm isn't worth the higher prices. The only difference I have noticed is the low end is easier to adjust and you get a smoother idle. I just burn one fuel in all my glow engines and they seem to be happy with the 15% Power Master. I did run into one brand of 20/20 that they didn't like at all, just can't remember the brand name, I thought it was the oil that caused the rough running but could never proove it.

rambler53

My Feedback: (494)

I had a .53 and .63 and a .91 so far, all ran good on Cool Power 15%, but I never tried anything else. I didn't need to.

I didn't want to ante up for 20/20 YS fuel, it's more expensive than booze and I was proving a point to former RCU member Loughbd it could be done.

hellyeh

I run several YS engines from a .53 right up to a 1.40 on 15% Omega . I run them dry after every flying session and that's it . I've had these engines sit for a year or better between outings (too many planes) and they start and run just fine . Haven't had to replace any parts yet , so apparently my method works OK . I won't say that specific fuel or one method over another is better or worse , but this has worked for me .

Jetdesign

My Feedback: (8)

I wonder if my issues were from the oil in the Wildcat? I used their 20/20 in my YS; it ran great for a month or two, then I had issues with the plunger, check valve, and maybe diaphragm.

Insanemoondoggie

Thanks for all the replies. I'mready to try a YS and will start out using the Omega . If I have issues I can always come back to this thread and try the other suggestions. Thanks again for everyones input.

ChuckW

I sold a sweet running YS-.63 to another guy in my club and he ran it on Wildcat 20-20. One day he was having trouble getting it to run right so I gave him a hand. The first thing I found was fuel lines hooked up incorrectly. It still didn't run well with those fixed so we pulled the fuel tank. There were globs of brown gunk, almost like grease. We also noticed it forming around the lip of his Wildcat fuel jug. That crud was all inside the fuel system. The fuel even leaves a greasy residue on your hands. I know the engine needs good lubrication but I just don't care for whatever they use.

My P-47 with a YS-91 has been sitting for roughly a month and a half. No after run oil or any special treatment. I took it out yesterday morning. It was in the low 40's and damp. Primed the engine, attached the glow driver and hit it with the starter. It fired right up without so much as a hickup. It has had nothing but Coolpower 15% since I rebuilt it. If I ever decide that I want more Nitro, I'll just step up to Coolpower 20%.

I've also been flying an OS 1.10-FSa lately and I gotta say, it might just give the YS's a run for their money. It is more powerful than my .91 YS and almost as good as the YS 1.10 even though it's naturally aspirated. Runs like a Swiss watch right out of the box, piece of cake to tune and leaves no oil on the plane.

pencon

I bought a used YS120sc at a swap meet for 125$. At first I tried to run it on 15% nitro. It kept stalling ,running too rich too lean etc . Just when I was about to give up on it ,I noticed leaky gaskets (bubbles)at the back cover. I took the whole engine apart, lapped every sealing surface including the regulator cover and valve cover ,all back cover surfaces etc . on plate glass with 400 grit emery cloth lubed with wd40 .I did notice warps in the surfaces (especially the valve cover )while lapping them in. put It all together and it runs like a clock on 15% no problem. 30 % way more power but 15% was not at all hard to tune. I think YS's develop the reputation for being hard to tune because they have more areas prone to leaking than do other engines .I would recommend any older YS that has trouble running to have the surfaces lapped . Like new again .

HellcatAce

My Feedback: (6)

I just use the PowerMaster YS 20/20. Use it in a .63 and .110.

OS engines like it very much as well.

Had an unfortunate crash caused by the battery unplugging during takeoff on a Dual Ace twin with OS .52's. One hit the runway hard and required new everything from the head up. The cylinder bore and piston top looked totally brand new after at least 2 gallons had passed through it before the crash!

Even use it in some of my 2 stroke engines and it works great!

Gray Beard

My Feedback: (-1)

I run the 1.20 NCs, other then a new diphragm and gasket every couple of years I have never noticed any leaking?? The reason the older YS engines had a rep as a hard engine to tune was they used the regulator pressure screw to adjust the low end and you can't always hear any changes in the RPMs, I found them easy to tune with a good tach. When I see people state things like Way More Power with the higher nitro fuels I always wonder what the WAY stands for, what kind of RPM readings are we talking about? 7 or 8 hundred?? 2000?? I have never seen any huge power or RPM gain with 30% but I have noticed the engines do run a bit smoother and are easier to tune the low end. Not a big deal when speaking of 20 bucks more a gallon. I would just like to see other peoples RPM gains with the different fuels.

pencon

Ok well 800 more rpm with an 18-6 master airscrew wide classic . I was getting 8200 with 15% and 9000 with 30 % Omega fuel .This engine will also pull 7500 rpm with an 18-8 wood zinger with the 30 % I noticed that same evening at home the valve clearances were quite sloppy so It might even improve next time I run it . The regulator Is no problem on my engine I've tweaked it slightly in from flush to clean up a rich midrange . My engine has a idle mixture adjustment as well .What would a 120nc get with that prop or any 18-6 ? I'm not insinuating that they all leak , I'm just saying it is perhaps more possible than other brands because of all the extra gasket surfaces.

Gray Beard

My Feedback: (-1)

I don't have a clue what an 18 inch prop would pull, the biggest prop I have hung on one of my NCs is a 16X8 and the plane/engine combo didn't like it at all. From 15% to 30% my big rpm increase is also in the 800 range. I just did a prop change on a Saito 100, went from a 16X4W to a 15X4W and got a taste over 1000 RPM out of that. The YS 1.10 took the place of the 1.20 some years back, they have the same power ratings and the biggest size they call for is a 16X6.the 1.40s big prop number is 16X10 and you don't get into an 18 until the 1.60. I think I still have the spec sheet for the older 1.20 out in my shop. I don't use Master Airscrews except on trainers, on my glow engines I mostly run APC or if I need wood I go to Xoar. I try to keep my RPM range from 8 to 9000 but I go by how the plane fly's more then the engine RPM. It's easy to do just by prop selection. I always have a few extra diaphragms in stock, when the engine starts acting funny or different that's usually the problem. I also have a gasket set or two on hand but I have them for my OS engines too. The only engines I have had leaking were OS Pumpers when the regulator needed a new Diaphrahm. YS service or Central Hobbies is where I get all my parts.

pencon

huh , well I guess the guy who sold me the SC wasn't ****tin me about the thing being a beast .I realize master airscrew isn't the greatest prop (local hobby store doesn't have much of a selection) but like I said , I did get 7500 with an 18-8 wood Zinger . 16-8 the motors almost floating the valves around 10.000 rpm . I've read I should be trying to keep the rpm around 8000 rpm. Maybe a 16-10 will get it there

Gray Beard

My Feedback: (-1)

You got my gray mater working so I walked out to the shop and found some info on the old YS engine. Only thing I had was for the 1.20AC and it was designed for F3A pattern flying and a HP engine. It has a top RPM of 12,500 and calls for props of 13.5X13-14 14X12-14 or 15X10-12. The F3A expalins the odd prop sizes they are calling for. The newer 1.10FZ has the high RPM at 9,500 and the 1.40 Sport is at 10,000. I have never had the bigger engines but the 1.60DZ is only going up to 8,500. I have nothing in the way of info on the SC model but you may want to look it up if you havent already to see what they are showing for the working RPM range and prop range. I have tried a lot of the shorter props with the high pitch and didn't care for them. I found the 16X4W a pretty good over all prop for my 1.10s but I have a 1.20NC in a CG Extra and it flew better with a 15X8 then any of the 16s I tried. All this is pilots choice though so you may like a faster plane then I do. I fly more stunt and like my planes to have more torque then RPM. They are also calling for 15% to 20% nitro with a 15% to 20% oil. Thay also state you can use Synthetic or Castor or a blended oil. The AC also replaced the SF. In the glow engine forum there is a YS support you can get more info from.

pencon

Gray Beard thanks but I've already looked up every scrap on the YS 120sc online and the prop range is supposed to be around 7500 to 8500 rpm they're supposed to be about as powerful as a 140 and more finicky to tune , although I've had no probs since I did the work on it .I had a YS91 about 10 years ago but it always dead sticked on me so I sold it. This is the first YS since and I have to admit ,they make an awesome motor .Here it is in my CMP Gee Bee http://www.youtube.com/watch?v=HKtwUUL0QBk

Gray Beard

My Feedback: (-1)

I'm very impressed, you can land yours and it doesn't flip over!!! On grass no less!! What type of LG did you put on it?? It's a plane we don't see a lot of at any of the fields but I still think it's one of the coolest looking planes ever built.

pencon

It has the great planes Robart oleos mounted on the wings but I also mounted rc car oil dampers on the front of the oleos. If you look carefully in the video you can see them when I land it . I have actually greased the Gee Bee in a few times with no bounce but of course tha vid cam wasn't on at the time ..