“It seems as though there’s a lot of competition in the gas engine market these days, and there are a few names that everyone is familiar with. Some of the big ones are DA, DLE, and 3W – just to name a few. There’s more to the gas engine game than just them! Over the past decade, several smaller companies have sprung up – some have stayed, and some have gone away. But, just because these smaller companies may not be as well known, doesn’t mean they don’t have good products at good prices!
RCGF, a Chinese manufacturer of gasoline engines, designs and manufactures engines specifically for the RC aircraft market. They have a line of gas engines as small as 10cc, all the way up to 120cc – they’re bound to have an engine to fill your need.”
This is a quote from one of my previous RCUniverse reviews, and it’s still true today! They’ve added more engines to their lineup, and have an even wider selection from which to choose. There are now two US service centers, and each RCGF engine comes with a two-year warranty! This review will be focusing on the new 60cc Rear Exhaust engine, and I can’t wait to show you what’s in the box! Have I got your attention? Read on!!!
Price: $409.99 (Price at time of review publishing)
Type : 2 cycle, reed valve type gasoline engine for airplane
Piston displacement Cylinder (cc) : 60cc (3.66 cu in)
Bore x Stroke (mm): 1.85 in (47mm) x 1.38 in (36mm)
Carburetor : Walbro
Ignition : DC-CDI (Computer Controlled auto advance, electronic ignition system)
Power supply: 4.8-8.4V
Maximum Output : 6.0HP /4.47kW
Requires: Gasoline, 2-cycle oil, ignition battery & propeller
Speed range: 1500 – 8800rpm
Fuel Required: Pre-mixed Fuel, 25-40 (Gasoline):1, Recommend:30:1
(90% high octane unleaded gasoline, Import gas into carbon fiber installations valves)
Lubrication Oil : 2 cycle engine oil
Suggested Propellers: 22 x 10, 23 x 8, 23 x 10, 24 x 9
Suggested Break-in Prop: 22X10
Spark plug: NGK CM6 Type
Cooling System : Air Cooled
RCGF Engine Package Includes: Engine, Electronic CDI Ignition, Muffler, Spark Plug, Gaskets, Bolts, Throttle Arm Extension, Manual, and RCGF Skull Pilot Decal.
The RCGF 60cc RE arrived in one of their newer style boxes, using only black ink and a brown cardboard box. Inside, I found a well packed engine, surrounded by plenty of soft foam. All of the parts were bagged, and RCGF made good use of the space by packing everything into a fairly small box! All parts were laid out on the table and nothing was missing. After the first inspection, I was happy with the quality of this engine and its components.
The ignition module looks very nice, and incorporates an nice nylon woven top layer on the spark plug cable. With its ability to handle operating Voltages from 4.8 to 8.4, there’s plenty of ingition battery options! The included M4F spark plug is an NGK CM-6 type plug, and appears to be well made.
The rear mounted exhaust system keeps the 60cc engine slim enough to fit in some pretty tight spaces. I like that they’ve included a heat shield to help direct airflow around the back of the cylinder and onto the muffler. Dual exhaust outlets keep the diameters small – that, in turn, keeps the over-all thickness of the muffler to a minimum as well! The included standoffs are made of aluminum, and seem to be well made. There were eight machine screws included with my engine, but no washers to be seen. Perhaps they got missed in my box – thankfully, I have a large box of spare washers on hand. But, if you were to buy some, they would need a 5mm diameter hole in them, and roughly 12-13mm in total diameter.
The operator’s manual, warranty card, and a great looking RCGF decal are all included with the engine. The manual is well written, and contains a lot of good information. I really love the new RCGF logo as well – it’s pretty mean looking, and still captures the aviation and engine themes very well!
The casting on the crankcase and cylinder/head assembly look great, and had no pitting or cast void issues. All of the machined surfaces were shiny and smooth as well. The rear mounted reed block, carburetor insulator, and Walbro carburetor are attached to the crankcase solidly and look great! I did run into one issue with the carburetor and reed block – I’ll talk more about that in a bit…
RCGF has included a nice RC-style throttle arm on the carburetor as well – this will make it easy to connect to a servo. The piston sports double rings to help with compression, and the exhaust manifold was clean and smooth internally.
I really like the slanted spark plug – it adds to the ‘compact’ nature of the 60cc RE engine. The plug’s sealing surface is cast, but it’s plenty smooth. RCGF has really done a nice job adding structural gussets to the crankcase to make the engine strong, and the mating surface of the exhaust manifold was in great condition. It had just enough ‘texture’ to it to hold the gasket well.
The four-bolt prop hub is a nice touch – it’s much easier to drill a prop for four holes than six. The end of the propeller shaft is also drilled and tapped to accept a 5mm spinner screw.
Setting up to Test Run
For this review, I will be installing the engine on my StegallHobbies.com Heavy Duty engine test stand. Though not much is needed in the way of breaking in the engine, it’ll be nice to start and test run an engine at waist level that’s not buried in a cowl! I started by reusing the template I saved from my RCGF 60cc twin engine – the mounting pattern is the same for both engines, so I didn’t take the time to draw up a new template. With the template taped to the engine mount on the top of my three ‘center lines’, I drilled pilot holes at each of the four mounting bolt locations. The template was then removed, and the holes were drilled to accept the 5mm machine screws. The stand offs were secured to the mount at this time, to get ready for the first engine fitting test. I did not add thread locking compound to the screws at this time, because I needed to remove the engine and its components from the mount for final finishing of the mount.
Before attaching the engine to the stand offs, I had to install the muffler and heat shield. A pair of gaskets took care of sealing the exhaust system. The throttle pushrod location was marked, and the Falcon 23×8 Beechwood propeller was drilled and test-fit to the engine. These Falcon props are my ‘go-to’ propeller of choice. They offer great performance at reasonable prices!
I removed the engine, drilled the throttle pushrod hole, and then remounted the engine to the engine mount for final fitting of all the components. Once I was satisfied with the location of all the individual parts, I removed them. After sanding the parts of the mount, I stained them, and applied the oil-based urethane sealer. When the urethane had dried, the engine mount was reassembled and the RCGF 60cc RE and components were reinstalled.
The complete engine mount assembly was then attached to my StegallHobbies.com Heavy Duty Engine Test Stand. By the way, the test stand is available at the following link: www.stegallhobbies.com/TripodTestStand. If you’d like to read my review of the Test stand, you can find that at this link: RCUniverse.com – Heavy Duty Engine Test Stand. Incidentally, I used the RCGF 60cc to demonstrate how well the test stand works!
Test Run Report
As I just mentioned, I had the 60cc RE mounted on the test stand to use for the test stand video. During the recording of that video, I was having a little trouble getting the engine initially draw fuel, and transition from idle to high speed operation. As it turned out, it was a two-fold concern. The first part was my memory. I could have sworn that the needles were supposed to be set at 1.5 turns out for the high speed, and 1 turn out for the low speed. Apparently, I was remembering what I had read in the 35cc engine manual, and NOT what was in the 60cc manual! By the time I had finished recording the test stand video, the needles were out to their proper setting at 3 turns out on the high and 1.5 turns out on the low. It was running better, but it still wasn’t transitioning well. My lovely wife reminded me that it was getting late in the evening, so I had to pack up for the day.
The more I thought about how it ran, I really thought that there might be a carburetor or fuel pump concern. I decided to remove the reed block and carburetor from the engine and do a little investigating. As I had thought, there were a couple of concerns present. First, there was some debris at the fuel inlet screen, causing a restriction in the fuel flowing into the carburetor. Second, the pulse port on the reed block was almost completely plugged by a thick, sticky foreign material. Because the port was plugged, there was not enough pulse pressure reaching the carburetor, and the fuel pump was not operating properly. Using a small pushrod, followed by a drill bit the same inner diameter as the port, I removed the substance. The debris was also removed from the fuel inlet screen, and the carburetor was reassembled. The carb and reed block assembly were then reattached to the engine.
I took the engine mount and stand outside in my front yard and reassembled the stand and mount. With everything back together, it was time to run the engine! I filled the fuel tank with 91 Octane premium, non-ethanol gas and a synthetic 2 stroke oil mix (using a 30:1 ratio). I closed the choke, and the engine was hand-flipped to start – it was quickly clear that the fuel pump was drawing much better, as it took many, many less revolutions of the prop to get fuel into the carburetor. A few more ‘flips’ of the prop, and the RCGF coughed and sputtered. I opened the choke, flipped the prop a half dozen more times, and the engine came to life for a few seconds before stopping. It was then that I realized that I had the idle speed set too low to sustain a good high-idle speed to warm up the engine. With the idle speed screw turned in a bit more, I started the engine again – this time it stayed running, and immediately sounded MUCH better than the first time I ran it for the test stand video!
I let the 60cc RE warm up for a couple of minutes, and made sure that the needles were a little on the rich side. As this was now going to be the engine’s first true test run, I wanted to make sure I wouldn’t run it too lean. The idle speed was set to 2,500 RPM on the digital tachometer I had connected to the ignition module, and the engine was running very well. I opened the throttle a few times momentarily to see how it would transition, and it was sounding much better than before! It transitioned without a hesitation, and ran well!
After approximately 10 minutes of running, I dropped the idle speed to approximately 1,800 RPM – the RCGF 60cc RE was idling well with no excessive vibration. Of course the heavy duty test stand was doing its job as well… Pulling the throttle to wide open produced a top end run of right at 7,000 RPM. This was short of the 8,800 RPM RCGF advertised on their website, but the engine will also gain more RPMs in the air. Plus, a slightly smaller prop would give a higher top end run as well. All-in-all, I was happy with a 7,000 RPM run for it’s first time running as it should.
Take a look at my video to see the RCGF 60cc RE gas engine in action!
I really like this engine. I like the rear mounted exhaust, and the over all fit and finish was excellent. I probably should have disassembled the carburetor and reed block before I test ran the engine, but the last few I have gotten from RCFG have been assembled without any concerns at all. As I said – after cleaning the fuel inlet screen and reed block pulse port, the engine ran very well on the test stand, and I have very high hopes that it will do even better in the air. Stay tuned to RCUniverse.com, as I will be mounting this engine in a new 122″ Decathlon from Seagull Models as soon as it arrives! I’ll add video of the Decathlon/RCGF 60cc RE combo as soon as it flies! For now, that’s all from my bench – we’ll see you next time! – GB
RCGF Engines – www.rcgfusa.com
Stegall Hobbies – www.stegallhobbies.com
Just Model Props- www.justmodelprops.com