Hi I just recently purchased a airplane with 2 OS wankel engines but can not seem to get them to run properly. When I fuel up the airplane they start leaking out of the carbs and wont run.....just sputter. I have checked the plugs and even replaced one with a 4 stroke plug hopeing this would help. Are the engines suppose to be carb up or can they be installled at a 45 degree angle like on the picture? Also any help with the needle valve adjustment setting on the low end or high speed would be great. The engines did not come with a manual so I had tried about every possible setting but they just seem to blow the fuel out of the carbs while trying to run. I leaned them out with the high and low needles but it still didnt seem to help much. Thanks and any help would be appreciated.

These have to have the OS wankel plugs, std plugs don't work. Did you ever see it run before you got it? Carbs should follow the std rule...spraybar at 2/3 tank height. Is fuel escaping the exhaust? If so they are flooded. If they aren't drawing if fuel the apex seals may be gone.
Mine are the old version so I don't know what your needle settings should be.

The engines weere suppose to have had only 2 flights before I got them . They are really clean and shinny inside and appear to have been used very little. The plugs that came with them are not marked so I have no idea what plugs they are. The carbs leak fuel when just sitting there and spray fuel when trying to run. Thanks

Hi,
I also just got a couple of wankels so I have no experience to offer other than yes, there is a wankel plug you are suppose to use, however that is not the reason fuel is pouring out the carbs. My guess would be that since they are nearly upside down and oriented below the fuel tank, they are drawing fuel and thats what you are seeing. I have a magnum 52 mounted inverted on a Cermark Javelin II that does the same thing. I have to hold the plane upside down (engine right side up) and start it this way, then I flip it over after I start it. It's a pain but what you gonna do???
Good luck,
FJ

I have a wankel of my own. You need the type r plug from OS for the wankels. Second and most important you need to use fuel that has 22-25% oil minimun or you will burn them up. They liked to be choked as well when trying to start them. Choke the carb and flip it over by hand a few times to get it primed and use an electric starter. They like to be spunup by the starter kinda fast when starting. Another tip is they like to drink fuel as well. I have burned through a 12oz tank on the test stand in about 5 min at full throttle. If you wnat to get rid of them let me know.

Well you've had some answers, I guess, but none of them address the true problem. Look at the picture. The carbs are below the nacelles which means gravity is pushing fuel into the carbs. It's unlikely that you'd ever get them to run too well that way since the mixture will change as you consume fuel, but if you flip the plan over, you should be able to get them to start and run. The long term fix will be to rework the mounts so you can get the carbs on the centerline.

You can download the manual from the OS website....

ksechler,
I would disagree, I think that couple of people basically have said that the engines are essentially upside down and the carbs are below the tanks so the fuel is drawn into the carbs and that is why he has fuel pouring out. Don't know now to make it more "plane" than that I have to hold my plane upside down (engine non-inverted) and flip it over after its running.
FJ

The O.S. Wankel engines can be mounted with the carbs in any orientation. Up, down, sideways, angled...the engine doesn't "care".

If the carbs are mounted below the centerline of the tank, fuel will siphon form the tank to the carb once the fuel line's filled. This will happen with ANY engine. With the Wankels, it happens a lot because many modelers have the centerline of the engine centered on the cowl, which also happens to be near the centerline of the tank, putting the carbs well below that...sometimes lower than the tank bottom.

As with any other non-pumped engine, the Wankels need to have the fuel tank mounted so that the centerline of the fuel tank goes throught the centerline of the carb, or no more than about 3/8" lower.

The O.S. Wankel will tend to start better if it's primed so that it's a bit wet. Use a fuel with about 20% oil content and 5%-15% nitro. We'd strongly recommend a high-castor content in the oil package. If the engine is under-oiled or over-heated, the apex seals will go and the engine won't have enough compression to run. If the rotor housing gets scored, the rotor, the housing, and the apex seals all need to be replaced.

You MUST use the O.S. Wankel glow plug to get proper operation.

Boattow:
What are you disagreeing with? I made your point. The carb should be on the centerline of the tank. If they are below the fuel will siphon out and pour out of the carb. We're saying the same thing.

You could add a Clien Regulator for each engine which should solve the siphoning issue.