Author Topic: Evo .36 experiences, let's hear some... (Read 5078 times)

wwwarbird · « **on:** September 25, 2009, 07:23:20 PM »

I'd just like to hear some of your experiences with the Evo. 36. I've got two N.I.B. that I have yet to personally run, but the couple I've witnessed seem to only like to run real fast. It seems like I've heard that elsewhere too.

Let's hear what works and what doesn't with them, props, tanks, fuels, all of the above...

Thanks!

ray copeland · « **Reply #1 on:** September 25, 2009, 08:36:28 PM »

Put one on my twister when it was new and could not make it run on the plane to suit. Of course this is a profile and your results may vary. The engine had about 30 minutes run time on it. Ran fine on the bench, but on this profile there was too much vibration, could not keep down the excesive fuel foaming. I used the meduim venturi and tried a variety of props and both of the mufflers with and without pressure. One thing i did notice is, if i can find a plane to suit it seems to have plenty of power!

Larrys4227 · « **Reply #2 on:** September 26, 2009, 04:55:03 AM »

I've got experience with 2 of them ..... both have run great. The 1st was mounted on a 38Special, 4oz standard metal tank on pressure, standard muffler, 10%nitro/20%oil, 11x4 prop. There were some issues with the remote needle assembly, so I replaced it with an OS spray bar/needle, with the large venturi drilled to accept. Also replaced the 'too cold' stock glow plug. For a long time the engine was difficult to turn over (tight going through compression), but after close to 100 flights its smoothed out and runs great. The 2nd engine came with the H9 PT-19 ARF (built for a friend getting into the hobby), out of the jug 10% fuel, stock needle, stock evolution 3-blade prop, small clunk tank on pressure, standard muffler. Replaced the glow plug before the first run. Ran the engine twice on the ground .... and then flew it. Runs great! It has 2 dozen flights on it now, and very consistent. Its also not nearly as tight on compression as the first engine mentioned. Not sure whats up with that, but they both run equally well.

I also have an Evolution 46 in an R/C plane .... also an excellent runner!

By the way, I add a shot of Armour All to all my fuel to prevent fuel foaming. Dont add too much or you'll get a deposit build up on the element of the plug, and consistency goes down the crapper. Just enough, so when you shake your fuel container, theres no foaming. Couple drops at a time.

In the photo, you'll see a muffler extension. I removed it 20 flights ago and it runs much better without it.

My vote is thumbs-up! I reallt like these engines!! Hope this helps!

Fly Safe! Larry

wwwarbird · « **Reply #3 on:** September 26, 2009, 08:34:36 AM »

Larry,

What plug are you using?

BTW, The 38 Special looks really nice.

Richard Koehler · « **Reply #4 on:** September 26, 2009, 03:17:00 PM »

Mounted my evo-36 after about a half an hour of short bench runs on my Banshee that had flown great with my double star 40. Used small venturi, bruline filter, and their needle. Needed the needle closed beyond the stop after the first flight and when I did this must have bent the spring cause I got a terrible runaway. Destroyed their plug. Got rid of the remote needle, and replaced plug with a thunderball RC with spraybar. On two different standard tanks and a uniflow got the fox burp. Engine returned to Horizon and they said the runaway had messed up the cylinder piston pinch and replaced the engine. Have only tried the engine on the bench so far and it seems to start and run great on the medium venturi/remote needle.

According to my R/C buddies this needle valve problem is usual and the fix is a piece of surgical tubing over the needle assembly. I've tried this on the bench and it seems to work. Am in process of deciding what plane I want for this thing. GOOD LUCK!

Leester · « **Reply #5 on:** September 26, 2009, 08:32:29 PM »

I had mine in a ARF Nobler, had to put fuel line on the needle also. It ran great right up to the time I burried the spinner about 2" in the ground. Need to built something for it.

John Paris · « **Reply #6 on:** September 27, 2009, 11:33:05 AM »

Wayne,
We have one in an ARF Nobler. As for the engine set up, I would use the smallest venturi and the pressure tap in whichever muffler you choose. You will need to find a way to control the needle valve assembly that come with the engine as it may vibrate around. I had problems until I loaded the engine with an 11" prop. Things went much better after that. I guess you can adjust pitch to get the speed you like as well as line length. We are currently using 18% oil fuel in a uniflow tank. I have not done much with it since the run got under control, so no input as far a 4-2-4 or wet 2 runs (that is what I did on the last runs). As mentioned above, the engine does appear to be a powerhouse.
John

Larrys4227 · « **Reply #7 on:** October 01, 2009, 07:14:11 AM »

Quote from: wwwarbird on September 26, 2009, 08:34:36 AM

Larry,

What plug are you using?

BTW, The 38 Special looks really nice.

Sorry, I guess I missed this when ya posted. Both the Evo-36's have OS-A3's. Other than a deposit buildup from ArmourAll on the tip of one plug element, its not been replaced in over 50 flights. The A3 is shorter than the stock original and thought this would give problems, but its been great.

FlySafe, Larry

FLOYD CARTER · « **Reply #8 on:** October 05, 2009, 04:35:28 PM »

My Evo 36 is one of the best-running engines I have. It is installed in an OTS Go Devil. The remote NVA works just fine, and I like the way it keeps my fingers away from the prop.

Floyd in OR

john e. holliday · « **Reply #9 on:** October 18, 2009, 12:22:29 PM »

Did you guys break them in with the muffler attached? I can't get mine to start iwht the muffler. DOC Holliay

Ralph Wenzel (d) · « **Reply #10 on:** October 18, 2009, 12:38:01 PM »

Quote from: john e. holliday on October 18, 2009, 12:22:29 PM

Did you guys break them in with the muffler attached? I can't get mine to start iwht the muffler. DOC Holliay

Same here, Doc. Mine wouldn't go with the muffler. Removed the muffler (understanding neighbors) and they lit up almost immediately. After about 30 minutes, they still don't like to start with the muffler. Why? ? ?

Mike Greb · « **Reply #11 on:** October 18, 2009, 07:30:34 PM »

I took me evolution 36 out of the box, bolted it to the airplane at the field, it started within a few flips and I was off flying soft patterns for breakin. I have not done anything with it this year. It didn't seem as consistant as the Evo 36 rc that I converted, but I have not really done any work on it either.

don Burke · « **Reply #12 on:** October 21, 2009, 10:04:23 AM »

Doc, the "electric finger" cures most balky starting engines.

My EVO was on an H-9 ARF. Started right up first time muffler and all, ran just fine. One-two flip starts on 10% nitro, 20% oil fuel. It's now in a Quicky Rat for testing. Doesn't like running WITHOUT the muffler. But when running steady with an 8-7 APC almost as fast as my K&B 40 TQ .

Derek Barry · « **Reply #13 on:** October 21, 2009, 02:33:27 PM »

I have 2 of the 36, both R/C. They are strong motors and they like the bigger props. Any thing under an 11'' prop and they like to run away. I may put one on my Vector ARF just to see what it will do.

Larrys4227 · « **Reply #14 on:** October 22, 2009, 05:40:58 PM »

Quote from: john e. holliday on October 18, 2009, 12:22:29 PM

Did you guys break them in with the muffler attached? I can't get mine to start iwht the muffler. DOC Holliay

The 2 I have experience with fired right up with the can muffler. Few weeks ago I ran my 38Special w/Evo36 and it ran strangely all day. I chalked it up to being around 95 degrees that day ..... hope to try it again this weekend. Temps are to be in the mid-80's.

Larry

Doug Burright · « **Reply #15 on:** May 30, 2014, 12:30:37 AM »

This might be a little late in the discussion, but I have two of the Evo .36 engines. Both of them are fitted with the stock, blue parts.

My first one, I purchased new, and am flying it on a Fancherized Twister, I built. It is terrific: I have been able to gain confidence to perform maneuvers that I was cautious to do earlier, due to other engines having some disconcerting quirks, and power issues. This engine has really allowed me to advance in my stunt practice! This plane has the tongue muffler, using the pressure tap.

The second Evo .36, I acquired a couple of days ago, used, and attached to a Hangar 9 PT-19 ARF, Ugh! Oh well, the engine is only broken-in on the bench, by someone else, and it too, is a fine running example. The PT was not flown until I received it, and the lead-outs were crossed, inside the wing. That's another story, but in remedying that, I found that the UP line is forward, and the DOWN line is aft in this plane. Fine with me, but they need to be moved rearward in the wingtip-it gets a little "light" on outside maneuvers. This plane flies with the big muffler, and could use a little more nose weight.

I have never run synthetic fuel through them- I am happy with 5/25, nitro/castor, and both airframes seem happy with an 11x5 APC propeller. The engines run great through the entire tank: a PERFECT 3.5 ounce wedge on the Fancherized Twister, and about a 3 ounce brass ACME on the PT. I need to secure the ACME tank better on the PT: it slides aft during the flight.

Well, this was supposed to be just a short report about my experience with the engine, and to comment, or question, why people are modifying their Evolution engines. Unless I'm missing something, they operate great, right out of the box.

Michael Massey · « **Reply #16 on:** June 01, 2014, 12:06:31 AM »

I do not have any of the Evo 36's but do have 2 of the Evo 60's. The 60's do not like castor!!!. While at our flying field a while back, one of our flyers was have some engine run problems with a relatively new Evo 36. He was using a fuel with castor. I talked him into using some of my all synthetic fuel. It pretty much fixed his problems and he is now a convert. The Evo's seem to dislike castor. Some are probably more tolerant than others, but if you are not using all synthetic in your Evo, please give it a try.

Richard Koehler · « **Reply #17 on:** June 03, 2014, 06:15:56 PM »

My first EVO-36 also burned up when the remote needle junped the stop. Horizon replaced it and I bought a OS R/C needle valve assembly that I screwed into the medium venturi. Here it is on my modified Banshee running a 11/5 Master Airscrew prop with a Brickhouse plastic clunk tank. I run in a wet 2 that goes to a lean 2 when the nose comes up. My only complaint is that it only runs about 6 minutes on 5 oz of Morgan 10% nitro fuel.

Mike Callas · « **Reply #18 on:** June 04, 2014, 01:56:52 PM »

I second the recommendation on only synthetic oil fuel for the evo engines.
Use the RC type fuel 18% oil and 10% nitro.
My only other mod besides an OS needle thru the stock venture is drilling out the holes in the tongue muffler.
It runs very strong.

ray copeland · « **Reply #19 on:** June 04, 2014, 07:51:50 PM »

Five years after my original post about the Evo.36 motor, i am now totally convinced this is a great control line motor! They need ample break in time!!! Mine run on the standard 10/22 half castor and half synthetic and with the os rc needle screwed into the medium stock venturi. Fuel usage is approx. 4 1/2 oz for the pattern. Prop is the TT 11.5x4.5. My Brodak P-40 is a dream to fly with this set-up.

fred krueger · « **Reply #20 on:** August 22, 2014, 10:46:54 PM »

I have been working with the Evolution .36 C/L engine on and off for about 4 years, with limited success, but just enough to encourage me to swap a ST34 for a 2nd Evolution. I had tried my own venturis, various prop loads, fuel mixtures, decompression and glow plugs with some occasional success, only to find the engine to be inconsistent.
This Summer I finally decided to check the cylinder port timings and I discovered that the exhaust duration is 150 degrees and the intake ports timed for 30 degree blow-down (total difference between intake and exhaust). The data I collected from researching stunt engine tests in Stunt News and other sources revealed that typical cylinder timings for stunt engines generally vary from 130 to 140 degrees exhaust and approximately 15 degrees blow-down. I'm stuck with the crankshaft timing as I cannot change it anyway.
Using trigonometry, I determined the distance I had to drop the cylinder to obtain the desired exhaust timing (I did one at 134 and one at 140 degrees); and the amount I had to cut at the top of the intake ports. The photos illustrate the machining work involved.
Dropping the cylinder dramatically increased the compression. I was forced to open up the head and also add head shims. I initially decompressed the engines too much and ended up removing a couple shims to restore power.
Dropping the cylinder also creates some sub-piston induction. I had some concern about SPI in a stunt engine, but I ran across an article stating that George Aldrich had done tests on stunt engines with and without SPI with no noticeable effects.
#1 engine is used in the video. #2 seems to have similar power characteristics. I am currently using a .185" diameter true venturi with a small jet tube. Fuel is 10% nitro, 24% oil (half castor). Prop is a Master Airscrew 10x5, 3-blade prop that measures 3.5 pitch. Ignition is provided by a Merlin 2005 plug. Launch rpm is around 11,000 in a 2-stroke. The engine settles to a fast 4-stroke within 1 lap. It breaks during manuevers, but doesn't accelerate. Fuel consumption is approximately 3 3/4 oz. for 6 1/2 minutes (a pattern takes about 5 1/2 mins.).
Bring on the flames!

Brett Buck · « **Reply #21 on:** August 22, 2014, 10:59:47 PM »

Quote from: Fred Krueger on August 22, 2014, 10:46:54 PM

I have been working with the Evolution .36 C/L engine on and off for about 4 years, with limited success, but just enough to encourage me to swap a ST34 for a 2nd Evolution. I had tried my own venturis, various prop loads, fuel mixtures, decompression and glow plugs with some occasional success, only to find the engine to be inconsistent.
This Summer I finally decided to check the cylinder port timings and I discovered that the exhaust duration is 150 degrees and the intake ports timed for 30 degree blow-down (total difference between intake and exhaust). The data I collected from researching stunt engine tests in Stunt News and other sources revealed that typical cylinder timings for stunt engines generally vary from 130 to 140 degrees exhaust and approximately 15 degrees blow-down. I'm stuck with the crankshaft timing as I cannot change it anyway.

The best running stunt engines I have are around 140-145. The 40VF varies but it's around 142-145. The "Brett" version of the RO-Jett is 144 (at least thats what they are supposed to be) and it is the version that runs the best. Others have 140 (OK but not as good) and 136 (not nearly as good). The lower the exhaust duration, the more excessive the power change in maneuvers and the bigger difference you get between 2 and 4 if you let it transition.

They also have very aggressive crank timing. I am not sure what you would want change on the EVO but it's pretty easy to make it wider if you need to.

The blowdown does seem excessive, but I don't have good numbers for that.

Brett

fred krueger · « **Reply #22 on:** August 23, 2014, 06:40:28 AM »

Brett,

Thanks for the response. I have the capability to increase the exhaust timing by placing shims under the cylinder flange. The blow down would essentially remain the same (~15 deg.). I will do some experimenting with that as time permits.
I am always hesitant to change crankshaft timing as removing material there could result in crankshaft failure (I had this happen in a smaller engine).

Fred