While at the Weak Signals Toledo Expo this year, I had the pleasure of meeting Henry from RC Aero Products. He told me that they had just started distributing a new line of engines. The JC EVO 28 is one of these engines.
The JC EVO 28 is an engine built specifically for the R/C hobby- it is NOT a converted industrial (weed whacker or chainsaw) engine. It has a two piece machined crankcase, a one piece cylinder/head assembly, and a rear mounted Walbro carburetor.
This engine also comes with an RCEXCEL ignition system that will work with 4.8 and 6 volt batteries, aluminum stand-offs for mounting, an aluminum muffler, and a CM-6 spark plug.
If this little engine swings a prop half as good as it looks, it'll be a real performer!
Engine Displacement: 28 cc Bore x Stroke (in): 1.37"x1.14" Weight: 38.8 Oz With Ignition and Muffler Enging RPM Range: 1,200-9,500 Gas/Oil Ratio: 40:1 Propeller Range (in): 18x6 to 19x6
The JC EVO 28 cc gas engine came in a plain white box with red lettering on it. When I unpacked the box, I found almost everything needed to install the engine on my airplane and get it in the air. The only items required are the bolts for the firewall, an ignition battery, a fuel tank set up for gasoline, and some gasoline fuel tubing. The machining on the crankcase is excellent, quite strong, and has a nice shine on the surface.
Some of the features I really liked were the rear mounted carburetor with choke, the electronic ignition system from RC EXCEL that will run on 4.8 and 6.0 volts, and the polished aluminum muffler.
Manual
The manual can be downloaded from the RC AERO Products website. I've also included a link in this review.
If you're replacing an engine with the JC EVO 28, the first step you'll have to do is remove your old engine. For this review, I'll be replacing the 1.50 cubic inch four stroke on my Wings Maker 1/4 scale Super Cub with the 28 cc gasser.
After the engine and mount have been removed, you'll need to make a template to accurately drill holes in the firewall. The template is easily created by temporarily mounting the stand-offs to the engine and tracing the ends on to a piece of paper. Tape your template to the firewall and drill the mounting holes. As the center picture above shows, the template was folded into quarters and lines drawn on the folds to place the mounting holes accurately on the firewall.
Once the stand-offs have been installed, cut a hole in the firewall for carburetor clearance. The manual states that the carburetor should have an inch of clearance to ensure proper airflow. Be sure to use a thread locking compound on the bolts that secure the stand-offs to the firewall.
At this point the engine bolts to the stand-offs, again make sure to use a thread locking compound, and the basic installation is complete. Now the ignition box can be mounted, the spark plug wire can be attached to the plug, and the wires can be run into the airframe.
Depending on your installation requirements, you may have to modify the throttle and choke arms to clear the stand-offs. For my installation, I chose to remove the spring from the choke and operate it from an extra servo. This set-up worked very well on my Super Cub.
Now, let's take this combination outside and get some pictures of the new engine installation!
After filling the fuel tank in my Wings Maker 1/4 scale Super Cub, I turned on the switch on for the choke, and flipped the prop about three times and the engine popped. The choke was opened, and after about 5 more flips, the engine started and was running strong!
At idle, the JC EVO was running just under 2,000 RPM, which, I thought, was very respectable, especially since the engine is not fully broken in yet. At full throttle with an 18x6 Xoar propeller, it was just under 9,000 RPM.
After firing up the engine, the Super Cub was taxied out onto the runway, and the throttle was advanced. The tail came up almost instantly, and within seconds, the plane was in the air. The JC EVO 28 had more than enough power for the 104" wingspan Cub, and throttle transition was nothing short of smooth. As I throttled back to land, the engine slowed down nicely, and the Super Cub came in and landed, and the JC EVO never once gave any indication that is wasn't going to stay running.
Check out the video to see her in action!
RC AERO Products JC EVO 28cc Gas Engine Or, Download the Video (24meg) CLICK HERE
Now, I'm not an expert when it comes to gas engines, but I've had a few over my years of flying. My previous experience has been with the CDI engines that have a flywheel. While there isn't any weight savings going to electronic ignition, they definitely are much easier to start, and run very reliably! One thing that sticks out in my mind when it comes to this engine is this: you don't have to go out and spend a lot of money to get a high quality, strong running engine!
