Michael211

My Feedback: (1)

I'm new to these engines... I have a brand new 90SP I need to break-in, and I've got 2 gallons of CoolPower 10% airplane fuel just sitting here. Can anybody tell me if this fuel will be ok in the 90SP engine? It has always ran great in my 40 OS SF engines!

I've read the label on these fuel containers and can't find the exact ratios and types of oil in CoolPower so I'm kinda at a loss here and don't want to damage this engine!

Thanks!

- Michael

Whistling Death

They recommend using fuel with 6% castor. I wouldn't use a fuel without it in this engine.

Michael211

My Feedback: (1)

Thanks for the heads-up! Can you recommend a good brand of fuel for these SP engines that's readily available in the US? I was able to borrow a few ounces of fuel from a fellow club member today, which had about 8% caster oil and 10% synthetic oil, and got the engine started on a test stand... it was quite impressive, turning the 18x12 Master Airscrew prop!

Nobody in my club has ever seen one of these engines run before so it got quite an audience. 8-)

Of course the idle was really rough as expected, but the mid-range was strong and smooth... there was however some oil leaking out around the prop-shaft which concerns me a little bit. Is this normal while running rich to break-in? We only ran it for 4 ounces then shut it down... I'd like a fuel recomendation honestly before I continue with the break-in.

Thanks ya'll!

- Michael

Whistling Death

They recommend the Model Technics Duraglo but that is made in the UK. They mention Morgan Omega 10% that has a 30/70 castor/synthetic mix, made right here in Alabama. http://www.morganfuel.com/omega_blends.htm They mention Byron fuels as well. I got on Byrons website to get information but the noise on there was so annoying I had to get off. I personally use the Omega 10%. It says use no more tha 6% castor but I don't know how to get around that. I'm not good with math I guess a guy could mix Omega and CoolPower to dilute it down to 6% but you would be playing with fire. I have successfully broken in my 120SP with Omega. After the initial few minutes of running the engine, I let it run at about 4000 RPMs. On a 16oz. tank I am getting 25-27 minutes of running time. Since it takes 6-10 hours to really get an SP broken it this is good. I have gotten it to idle at around 1300 RPMs so I figure it is broken in.

My 90SP leaks around the drive washer too. I don't know how normal this is. I have heard that they leak less after they get broke in but I find that hard to believe. The real key here is keep it tuned to run smooth. If it is running rough at idle you need to get the low end adjusted till it idles smooth. Don't worry about getting real low RPMs on the idle yet because it won't idle reliably untill you get it broken in. It will vibrate like crazy when new but it eases up as it gets more running time. One other thing. I would go ahead and get an O.S. muffler to replace the RCV muffler. The RCV muffler will fall apart after a while. Use it during the breakin process and then replace it before you get ready to fly.

RCV Engines

Hi

I have spoken with our Chief Technician and can advise that CoolPower 10% would be OK in our RCV90-SP.

Fuels must have an oil content of around 15%, with no more than 6% Castor Oil. However we do recommend the use of high quality fully synthetic oils giving clean running and longlife. All of our engines are tested using Model Technics TechPower 10. Some alternatives would be Morgan Omega 10% (as mentioned above) and 10% Byron Premium Sport 'Standard'.

Best regards

Stephanie

Michael211

My Feedback: (1)

Thank you for checking on this Stephanie!

So in summary, there should be no problem running the full-synthetic CoolPower 10% fuels which lack Caster oil? On my next break-in run I'll try 4 ounces of the CoolPower 10% I have and just see how it handles it.

Also can you check with your techs regarding the leaking of oil around the thrust washer (the part of the engine that turns with the prop)? I was seeing quite a few drops of oil coming out of there on my 1st 4oz run... will this clear up once the engine has been broken in and adjusted to a leaner mixture?

Thanks Stephanie! RCV official presense in this forum is 1 of the leading reasons I decided to try this enigne out. It's garnered quite a bit of interest from my fellow club members here in Houston... everybody's wanting to see how it performs. Nobody in my club has ever seen one before.

Funny thing is that everybody thinks it's a very "pretty" engine and they don't like the idea of putting it in a Mustang where the cowling will hide it from sight... LOL!

- Michael

Whistling Death

Just make a clear cowl..........

RCV Engines

Hi Michael

I have checked with our Chief Technician and can advise that the oil leaking you mention from the thrust washer can happen and tends to reduce over time. If it does persist you will require a new bearing seal. Let us know how you get on.

Best regards

Stephanie

Michael211

My Feedback: (1)

Thanks Stephanie... I went back and re-read the instructions again yesterday. Your instructions on the break-in procedure do state that the engine will leak oil (doesn't specify were from) until the break-in is complete. So it makes sense to me now, given that the engine only has 10 minutes of run time so far and it's set extremely rich, that some oil droplets will make it past the front seal.

I did a 2nd run on it yesterday for about 6 minutes and didn't notice very many drops of oil coming from the front seal this time. Also the engine is much "free'er" and I was almost able to start it by hand flipping.

I'll continue the break-in runs every time I go out to my club field, and see if the oil leak goes away as the engine is leaned out over time.

Thanks for all your help!

ps. I set the 90SP with it's 18x12 break-in prop up next to another member's H9 P51 Mustang with an 91 OS Surpass with what must have been about a 14 inch prop... the difference in props is INSANE! LOL! Can't wait to see this engine mounted in my Mustang with a 15 1/2 diameter 4 blade prop. 8-)

- Michael

Michael211

My Feedback: (1)

Hey ya'll!

I ran my 1st 16oz of CoolPower 10% Nitro in the 90SP on the test stand this past Wednesday. What a difference it made!

This was my 2nd time to run the engine. The 1st time I ran it I'd borrowed a tank of fuel from a fellow club member... I can't remember the brand, but the specs on that fuel were that it had some 8% Caster oil in it. I was trying to follow the RCV's instructions to the letter and was afraid to run the CoolPower I had (which I've used in my 2 cycle OS Engines for years now).

The 1st run with that other fuel the engine puked and dripped oil all over the place. It was a rather cool day so I had a jacket on and I was covered with oil droplets by the time I'd run some 6 oz or so of that fuel thru the engine. It was puking droplets of oil out the crankcase vent and dripping oil out the front seal really badly as the engine ran.

So this past Wednesday I took it back out to my club field and mounted it on the test stand again and this time ran a tank of CoolPower 10% full synthetic fuel thru the engine and it was a totally different experience! No more puking oil out the crankcase vent tube, and the drip at the front seal was nowhere to be found, and the engine seemed to me to run alot "easier". Also after a 20-25 minute run on the CoolPower the engine was ALOT cooler when I shut it down (err, actually ran the tank dry).

After 1st running it with the fuel with Caster Oil, the engine was extremely hot and untouchable for some 5 or 10 minutes after I shut it down and was smoking pretty badly from the heat.

This time though with the CoolPower (and a much warmer day, in the mid 70's) the engine didn't smoke at all after the run and I was able to immediately put my hand on the cooling fins... they were about as warm as a hot water pipe. Within 2 minutes I could touch the muffler and it was cool to the touch.

I think it might be of some benefit for anybody with these engines to try a few ounces of CoolPower (or some other full synthetic oil based 10% nitro fuel) and see what you think. It seemed to work alot better than the caster oil based fuel on mine!

Also I've read alot of posts about the starter bolt coming out of the engine. I can easily see how that would happen, especially if you try starting it with the throttle very far above idle! On heli's I use a starter wand with a 1-way bearing in the wand that lets the wand spin at whatever speed the engine wants once the engine starts. It makes it ALOT easier to remove the wand from the running engine also!

But on the RCV engine when using their wand to start behind the prop for the 1st time this Wednesday I could definitely feel the wand was in a bind as I tried to remove it once the engine started running. I started the engine at about 1/4 thottle and it was laboring against the starting wand as soon as it fired up. Obviously this sucker is trying to unscrew the bolt from the engine.

RCV engineers seriously need to look to the heli world to see how an engine should be started with a wand. When the engine starts to run on it's own, that wand needs to be able to freewheel at the engine's speed so that it doesn't 1) drag the engine down and 2) unscrew the starter bolt!

My guess is that the only workaround is to be sure to start the RCV with very low throttle setting... perhaps 1/8 throttle or less. I had to physically yank the starter out of the bolt to get it loose after the engine started. This is an issue that I don't like one bit.

Regards!

- Michael

AmpAce

Michael,

Thanks for posting the information about the RCV SP engine. I'm contemplating getting one of the 120s, and also have about a gallon of Coolpower fuel from another application.

Will be following this thread with interest!

AmpAce

Sparkey

My Feedback: (15)

Very good posting .
It certainly has saved me a lot of searching on fuels and running in .
Way to go RCV as they are very helpfull when needed

What would a good size breakin prop be for the 120?
Sparky

trysforscale

Sparky ,
The 120 sp uses a 20 x 12 prop for breakin !!! I have run my 120 with a 22 x 10 too . But , I use zinger wood props and they are a bit on the light side . The sp engines like a heavy prop to give them a bit of flywheel effect . Oh , I started useing cool power 10 % too . really made a difference .

RCV Engines

Hi

At RCV we now do all our testing on Techpower 10 which is a fully synthetic fuel. We find that that runs extremely well. We have no direct experience with Coolpower 10 so we are unable to recommend without qualification.

RCV

Michael211

My Feedback: (1)

It runs very VERY well on Coolpower 10% plane fuel in my experience with this engine this year. Also is much cleaner than fuels with caster oil in them... my engine still looks like brand new! If you've seen engines that have been run with caster oil you'll know what it does to them and how it tends to gum them up over time.

Regards!

- Michael

Joe Lott

Michael, RCV, or anyone else,

I've run a gallon of Omega 10% through my 120SP. The break-in vibration has lessened and parts are no longer shaking loose. I think I will make the switch to Cool Power 10% and see how things go. What kind of performance are you getting with the Cool Power, or any other fuel with synthetic oil only? My engine will consistently idle at 1300-1500 rpm with a top end of 5700 rpm lean. I'm swinging a Master Airscrew 18 x 12 for break-in and will be going with an 18" 3-blade prop. It's a custom hub with Soloprop blades and weighs in at around 12 oz., hence my question about the performance. The weight of the prop should enhance the flywheel effect and the pitch is adjustable. Does the synthetic formula yield performance on par with the synthetic-castor blend fuels?

Sparkey

My Feedback: (15)

Re gards Cool power

Went to local hobbie stor and bought 10% coolpower today.
Question Label says Cool Power Total synthetic model engine fuel MV.
18% lubricant
No marking of ant castor in it which Rcv requires 3 to 6% I believe.
So where am I at here` do I use this without Castor or should I add castor
\

Sparky

Joe Lott

Sparkey,

The Cool Power MV uses a multi-viscosity synthetic oil and no caster. I'm going to try the Cool Power (and add no caster) based on Michael's experience with it. Keep in mind that RCV stated above that they now test with fuel using fully synthetic oil.

I've notice that when running the Omega 10 (a synthetic-caster blend), my 120SP does get very hot, but not enough to overheat. I have been running it in 4-5 clicks on the rich side for safety's sake. If the Cool Power lets the engine run cooler and smoother and the performance is equal to or better than fuels with caster added, it will be of great benefit.

RCV Engines

Hello from RCV

We used to specify that fuel used on our engines had a small amount of castor in it. However, for some time now we have switched over to using a fully synthetic fuel for all our test work and are very pleased with the results. We now recommend either a fuel with a samll amount of castor or a fully synthetic. We do not test all fuels and the coolpower is in this category, but as long as it is a good quality fuel you should have no problem with a fully synthetic.

RCV Engines

Michael211

My Feedback: (1)

No problems with Coolpower 10% here, my 90SP engine still starts right up and runs very well. I don't think there was ever anything "special" about Caster Oil other than it's ability to lubricate the engine's internals, and the fully synthetic oil fuels available today seem to do just as good a job if not better than the Caster Oil did (my 90SP runs much cooler with Coolpower full synthetic oil fuel for instance). Some "old-timers" at my flying club are still convinced all model engines MUST have caster oil in them to last though (they even add MORE caster oil to their fuel's which already have caster oil in them)... hard to teach an old dog new tricks, apparently. Oh well.

- Michael