OS GGT10 TEST

After the success of the OS GGT15 petrol/glow engine you would have been on a sure bet they would not stop there. This engine is the next in line and it is, like the 15, a winner. At 10 cc it is a good size for many models and certainly for multi engine aircraft. No fuss start - a normal glow power supply does the job but be careful of power panels as some will kill the plug.
As an example of the testing, I recorded 9,974 RPM with an APC 13 x 6 propeller On a 14 x 4 I recorded 9,019 RPM.
Fuel was both Morgans Coolpower blue oil and also Deluxe Power Model oil with 95 RON petrol. The engine performed very well on both fuels and, as a side note, the exhaust efflux from the Deluxe oil was just a honey colour - no black specks or black oil.
My full review will be in Australian AIRBORNE magazine # 263 and later in the UK magazine RCM&E

[@toddfrendell6837]

The bit about the electric starter was courteous, but you gave it a flick anyway and it displayed much enthusiasm! Cheers!

[@lash6942]

That looks great Brian

[@martysk8r]

Simple, powerful, and not near as much oil blown all over the plane. I think I like it.

[@zappbranigan8674]

Nice video Brian! Would you recommend these over the .55 ax? I'm building a Sbach (first build) just wanting to know if they are worth the extra 200 dollars? Thanks

[@BrianOilyEngines]

Yo Musicalanus, Both good engines but I would go for the GGT10 as it is a much later engine, has very good power and is available so parts will be around for quite a long time. I don't know the future of the 55 - I tend to think that OS will not continue with these engines now as they are discontinuing several glow engines that have replaced by petrol versions and I also think that glow engines in the main have a limited future for anything under about 10cc - even small engines will be subject to demand. Err, I have to ask...that pseudonym of yours...anything to do with 'blow it out your ****? Regards Brian Oily.

[@pepecondor55]

Hi Brian, What side and mark of propeller do you recommend for the Gtt10 taking into account that I fly to 700 above sea level, and what oil mark and proportion do you recommend? Thanks and congratulations for the video

[@BrianOilyEngines]

Yo Josè, Nice to hear from you and I am pleased you enjoyed my GGT 10 review. I recommend a 13 x 6 propeller for your altitude as you need a bit of extra pulling power and the 13" diameter is good for that. The oil that is very good for that engine and recommended now by O.S. is DeLuxe PowerModel 2T-S and 25:1 will be a safe mix - that is - 40 cc added to 1 litre of 95 grade petrol. If you need to know more about that oil, please email me on [e-mail] and we can discuss it more and you can tell me where you are from. Regards Brian Oily.

[@allengentz7572]

Hi Brian, What sort of glow plug is it using (Four Stroke,No8 etc)

[@BrianOilyEngines]

Yo Allen, The engine comes with a special plug for petrol operation - it is an O.S.G5 however - I have experimented and had good results with an OS F plug but I do not know how long this plug will last compared to the G5. Thank you for your interest in my tests. Regards Brian Oily

[@halilemrecubuklusu6644]

Dear Mr.Winch, thank you for this video. how is the fuel consumption? is it economic like evolution 10cc? evo10gx can fly 3 kg airplane with 12x6 prop @12000 rpm, 300cc fuel tank near 40 minutes. thank you p.s. i am dissapointed with relibility of evo10gx. it is damaged because conrod bearing is collapsed with crank pin. :( below 100hours work time:(

[@BrianOilyEngines]

Yo Halil, I am pleased you enjoyed the video - I certainly enjoyed running the engine. These new era small petrol engines have very low consumption figures - almost like...just SAY the word 'petroil' and they will run for ages. The figures would be almost identical to those of the Evo 10 which is good if you are using it for a scale model and free area is a bit tight as a small tank will give you good running time. With the propeller you intend to use for the model, run the engine at close to maximum RPM for one minute and note how much fuel it uses. Using this calculation you can work out the tank size that will give you a reserve unless you are a 'rev head' and run the engine full RPM for the entire flight. If so, make allowance for this. Thank you for your interest. Brian OIly

[@luis114avi]

...¿no te echó a arder la gorra con lo calentito que está el motor? ¡que barbaridad!!!

[@BrianOilyEngines]

Yo luis, I sure would like to talk with you or answer any questions you have but my only language is Australian - almost identical to English - and I cannot translate what you have said. Can you translate for me? Regards Brian Oily

[@12volt50]

Hi Brian, Just took my GGT 10 on it's first flight today (Avistar Elite, 10x8 prop, 8 oz tank) and on my first flight I was worried because it seemed to lack power but after a few additional flights the power increased and fuel consumption decreased (about 5 9-10 minute flights so far). The only issue I seem to have is I can't seem to get the idle down as far as my nitro engines. It does idle nice so do I just need more break in time? Thanks for the video and appreciate reading you comments. Glad you cleared up the needle adjustment being the same as nitro and agree it is written differently. Love the sound of the engine! I have flown with the plane with a .46 and even had a .55 in it and think the GGT 10 thus far would fall in between the two. Before my first flight I did have to move the pump because it was getting too hot and causing the fuel to bubble (which OS comments on in the manual. Once I moved the pump it ran fine.

[@BrianOilyEngines]

Yo Vince, Why such a small propeller? The engine will give very high RPM on that 10 x 8 but the load is too light for a low idle. You should be looking at larger props than that - nothing less than about a 12 x 7 as specified in the instructions. I went right up to a 14 x 6 propeller and the engine still gave a very good performance. They are a very nice engine and they will give good, long service provided you do not 'wring' them out too hard and I think you would be doing that with a 10/8 inch propeller which is more suited to a .40 size engine and even on that the RPM would be very high. Try a larger propeller and I'll bet the idle comes right down to about 1,500 or lower as the engine beds in a bit more. Let me know how you get on. My email address is [e-mail] Regards Brian Oily

[@12volt50]

My mistake I have a 12x7.

[@asafgl4281]

Does that blue pump is necessary ???

[@MagicMagicSwirl]

Hi Brian. Serious question here - I've never ran a petrol engine, only glow engines. Do petrol engines leave the same oily residue all over the plane from the exhaust that a nitro plane produces? This question is burning a hole in my brain...

[@BrianOilyEngines]

Yo Banana(?) Save your poor burning brain - all is well in the oil department as you use generally less than 5% oil and, if you use a high quality oil, the most you can expect is a few black spots here and there like fly specks. So...the good news is...no oily models (and no oily hands like mine). Thanks for you interest in my reviews. Brian Oily

[@MagicMagicSwirl]

Brian Winch Thanks very much for your detailed reply! It seems to me that this alone might make the 3x price tag over glow engines worth it.

[@pepecondor55]

Hello Brian, I'm from Argentina. I tell you my engine never worked with the original fuel pump. place by a Perry pump and now the operation is perfect. The oil that you recommend in my country I can not get it. Here I can buy the Motul.oil I am surprised by the ratio of 25: 1 that you recommend. Is not it much oil? The manual suggests 50: 1 or 40: 1. I would like to know a little more about your suggestion with more oil concentration. You have knowledge that someone else has had a problem with the pump. I made the claim to OS and they sent me a new pump and the problem continued. I do not achieve good driving stability and the operation stops unexpectedly. The mix adjustment I have not been able to achieve, I have tried in many ways. I am a modeler of more than 30 years, I think I have good experience in adjusting the engines. I sent you a link to my engine running with the Perry pump. I hope an opinion of you about it, I think your experience is worth a lot. It is a pleasure to exchange opinions with you. Best regards Jose PD When I send an email to your email address, it is rejected, confirm your email well please.

[@BrianOilyEngines]

Yo José. Your engine certainly runs well but so does mine in my test video and it is on the original pump. I really do not know what caused the problems with your engine and pump and I must say it is the first one I have heard of so far. Maybe some small point that went unnoticed and I think I would have found it if I had the engine but....that is not possible. By the way, that TERRIBLE spinner looks like the dog chewed the clearance hole in it (HoHo). It would definitely be unbalanced and will put an unnecessary load on the crankshaft bearings. Regards Brian Oily - My Email address is [e-mail] or [e-mail]

[@exxocaliber]

Hello Brian, may i ask you about the carb. The manual says the needle valve is the other way around from a glow engine. Does that mean that if i want to richen the fuel mixture i screw it in (clockwise)? Sounds strange to me. Thanks! Best regards Victor Sweden

[@BrianOilyEngines]

Yo Exxo, You really need to read the instructions several times and examine the engine as well. The slotted screw beside the needle valve is the mixture control valve which, really, rarely if ever needs altering but, if it is and the engine runs okay, don't change it again. That adjustment moves the fuel jet (spraybar) over a fixed needle in the rotor so, if you wind it in you need to wind the main needle out to richen the mixture. It really is the same tuning procedure as normal but put in a different way in the instructions. You wind the needle from a lean mix which is the way it is always done. Being a petrol engine it will stop rather than run lean so that is an indication for you.If you read section 3-ADJUSTMENTS a couple of times if will be clearer for you. If you want to send me your email address I will send a copy of my review. Contact me on : [e-mail] Regards Brian Oily

[@amartinezperez]

Hi Brian. That's a very nice engine and a great review. Do you know how much the plug lasts? And, is it really difficult to hand start? Will it be possible to make the breaking-in and continue after it without using a starter? Thank you very much.

[@BrianOilyEngines]

Yo Alberto, Provided you use the correct current - no more than 2.5 Amps - the plug is very long lasting but...most power panels are not good for this plug. I use and recommend and RCATS glow driver and I have never blown a plug with this piece of equipment. As to whether it is easy to hand start - well - what can I say? You have seen the video of it being hand started first flick so..... Actually, I hand start almost all engines but...I do use a glove just in case. This engine is very docile to start by hand and I see no reason why you would have a problem Thank you for your interest. Regards

[@amartinezperez]

Hi Brian. I'm glad to read that. I always hand start all my engines. I even don't hace a starter.

[@jmarismendi]

Helo Brian.I have an OS GGT10cc and GGT15CC not work well with the original pump , buy 2 perry pumps and now work perfect. It happens with bombs OS that bring these engines ? I have tried everything possible but do not work with the OS that comes with original pump motor, pump perry has been my solution , someone has an explanation , thanks.

[@BrianOilyEngines]

Yo Jose, I can understand you might have problems with one engine - maybe a manufacturing fault (quite rare with OS) but not the same problems with two different engines. The only problems I have information on regarding these engines all stem from incorrect petrol or oil, no filter or a filter not fine enough, altered mixture control valve setting, fuel tank problems such as the breather tube being too long, foreign matter in the tank and glow plug problems when an incorrect power supply is used as the plug cannot tolerate an excess of 2.5 Amps. I know many modellers who have and use these engines and never have a problem and, as you can see, the engines (stock standard off the shelf engines) I have in my tests run perfectly and they still do. You need to very carefully analyse the procedures when you changed over to the Perry pumps as something else you did cured the problem. Regards Brian Oily

[@jmarismendi]

I understand perfectly, use a filter between the carburetor and the fuel pump and a filter between the tank and pump, oil syntetic motul 800, and fuel 95 octane proportion 35-1, needle low original position according to the manual, 14x8 propeller, fuel tank close to the engine and short hoses. the engine starts at once and the transition does it well but at full throttle the engine starts to vary its rpm, refining needle high and gives good but after a while begins to fail as if he were fuel, acceleration becomes slow and defective, so does a friend who has a GGT10cc, have spent more than 20 hours making him as much as possible but I have not managed to sing while having more than 20 years of experience in model airplanes, the solution was to place a perry pump my engines and yesterday my friend took my advice and perry placed a bomb and also fix your problem, see your videos and tips are excellent and I can not explain that to us the pump will not work. After the engine is running perfect with perry pump, I put again the original OS pump and the fault appears instantly, and had purchased 2 pump original OS but give me the same problem, which improved by placing the remote pump motor and it got very hot and generated many bubbles and the failure was worse. I can not find explanation to this problem, only OS pumps do not generate enough pressure and supply fuel to the carburetor. thank you very much for your help

[@BrianOilyEngines]

Yo Jose, I have two considerations at this point - the capacity of the fuel tank and the length of the tank breather tube. If you use a very large tank the pressure variation is too great for the pump to control. The other consideration is the length of the tank breather which, if too long, will cause tuning and running problems. I would consider a maximum of 100 mm (4 inches) would be the safe length for those engines. It seems to me your engines are running hot and this is likely to be caused by overloading with the propeller size. I would not use anything larger than a 13/8 narrow blade on the 10 cc engine and the 14 x 8 would be okay on the 15 cc engine. The default propeller for a 15 cc engine is a 14 x 6 as this is the middle range and will give the performance according to the manufacturer's figures. Try some of these ideas and let me know how you get on. Regards Brian Oily

[@AlpineWarren]

How is the idle speed and reliability at idle? Thanks!

[@tonyblewitt6159]

don't buy one of these . You will regret it also the pumps are like $90 (USD) to get a replacement and the engine seems to have an appetite for glow plugs

[@TestECull]

@Brain Winch You reckon this tech will filter down to cars within the next 5-10 years? It'd be an engine power revival for 1/10 and 1/8 RC, particularly with bashers, if we could run gasoline using the pit gear and rock simple ignition systems we currently burn glow fuel with.

[@davelowets]

@@TestECull It's been tried by manufacturers for the smaller (.30) 1/8 scale car engines a few years ago. They have ALL been discontinued because of the massive amount of connecting rod failures of those engines. It seems that the gasoline/oil mix just didn't work well with the small bearings and clearances of the smaller engines, and they ate rod bearings very fast.

[@mapes12]

Where did you get the Start Ya Bastard hat?

[@AlpineWarren]

1/8" or 3/32" tubing best for this?

[@BrianOilyEngines]

Yo Warren, For some reason your question did not come up as an alert on my computer - I just found it now while answering another reader. Sorry I missed you. As to the tubing, 1/8" is quite adequate and that is the diameter tubing I use for ALL my engine tests including those you see on this site. Thank you for your interest. Brian Oily

[@AlpineWarren]

Thanks mate!

[@BrianOilyEngines]

To all modellers, Some watcher made a comment about modellers buying 'on line' instead of the local dealer. Well, I buy almost all my requirements 'on line' from my favourite local hobby shop in my own country (Australia). All hobby shops sell 'on line' now or they just cannot compete. Why would I want to buy personally when it costs me a load of cash for petrol then try to find a parking spot (and maybe pay for it) and spend at least an hour away from my workshop when I can ring the hobby shop, order and pay for the items and they will be posted at a much lower cost than it would have cost me to go personally. Incidentally, my main 'local' hobby shop is now about 500 km from where I live but a couple of seconds by phone or Email. The previous close by hobby shop went 'off the boil' and doesn't service the model industry so well so...I changed hobby dealers. For sure, buy 'on line' but from your 'local' hobby shop and they will be able to stay in business and be there for you. Brian Oily

[@pepecondor55]

Your email address is rejected when I send it to you

[@AlexBongRCFunLand]

look like O.S discontinued this engine. too bad.

[@billjones3071]

Only reason to buy this engine is if you can't get glow fuel, can't beat power to weight of a glow engine plus the cost of a gas engine not worth it plus your car and house will smell like gasoline, nitro is the best set it up right and your clean up is minimal