I had bought a Fuji 64 to power my Ziroli Dauntless. I was pleased with it at first but then the problems started. While flying at about a 3/4 power setting the engine went down to about idle speed then kind of surged up and down at very low power until I could bring it in for an emergency hard landing. Checked for obvious problems then ran it on the ground to see if I could duplicate the problem. Well I was able to duplicate the problem on the ground and then the engine stopped suddenly with the crankcase broken at the cylinder attach bolts. It was replaced under warranty with a new engine.

Today I was flying the same Dauntless with the new engine and it developed the same problems while flying. This time I was not so lucky with the landing, damaging the plane and Robart retracts badly. Inspected the engine and it looks like it is starting to crack in the same area of the crankcase as the first one did.

I am sending back under warranty just like the first one but even if it is replaced again I am VERY nervous to use it.

WOW,
I would be nervous also.... Is your plane vibrating ????

No, nothing more than any other single cylinder gas engine. I have read other posts about Fuji engines having the cylinder break from the crankcase and that was my experience with the first one and this one looks like it is going to do the same. I also have a Zenoah G38 that I have used for several years on a Nieuport 28 and it performs great.

Scott

Hmmm....Breaking like that just isn't common, but we'll be glad to check it out. If the engine starts running rough and detonating, it could be too lean. Sometimes going lean is a sign that the screen in the carburetor is getting full of dirt and debris. Most fuels have to be well-filtered to protect our engines. There's more garbage that gets into fuels than one would normally imagine.

I have sent the engine in for you to check out. My thought is that with the crankcase cracked ( which was verified by an NDT shop ) the engine has lost some of the pressure and vacuum needed for the carb to work properly resulting in the loss of power.

hey big scale, don't feel alone...I've had three fuji64s and had issues....A year ago was flying my 1/3 scale Fokker triplane at an airshow....after three minutes in the air most of the engine departed the airframe and dropped to the ground...I had to deadstick a 45lb triplane which was now severely tail heavy...not easy, but managed to save it......the crankshaft SHEARED...was running 32:1 pennzoil and slightly rich mixtures ...........put on a brand new fuji 64.....was flying three weeks ago again see something falling from the airplane; the muffler...oh I thought, will have to land hot cuz idle high but no big deal....find out the muffler AND part of the cylinder cracked off.....somethings up...I just bolted on the third and final fuji 64 but I might just take it off and refit a different brand...None of my Zenoahs ever did this...

I've read other posts on this forum dealing with various Fuji engines breaking. Like you silver cloud, I have never had any trouble with a Zenoah I own. By the way I was told by Hobby Services that the crankcase crack was my fault because I had ran the engine hot or lean at some point but they would sell me a new one for a "special" price or I could pay a $15 "non-warranty inspection charge" and they would send it back even though it is still under warranty.

Scott