Mine is really running well these days. I had put it aside for a while, because I was having so much fun with the 68 inch Velox and the beastly DA-60. Now that I am signed up for my first IMAC event, the best plane I own for that is the Syssa powered 78 inch EF Extra. I think that my fuel tank was some of the issues I was having, but now with the Fiji bottle tank, and heavy clunk it is running perfectly, even with 6, single flip starts in a row yesterday. On all of my gassers now, I am running Stihl Motomix which is 100% 92 octane gasoline (no ethanol) with HP Ultra mixed in at 50:1. It is clean, has almost zero odor, and runs so well. It is interesting that Stihl will double their warranty on their power equipment to 4 years if you run it! The downside is it is pricy at $7 per liter, but that works out to about 2 bucks per flying day, so what.

I just started my Syssa for the first time today, and I'm not having the easiest time.

Turns out I had an air leak in the T. Bypassed that, and no bubbles, but it still won't fire by hand, with the mixture screws set as per the directions. Making a very slight change in mixture sometimes has a great effect and sometimes seems to have no effect.

Finally gave up after a muffler bolt fell off.

Anyway, it acts like a fuel related issue. It will act like it is somewhat rich, but shut down like it starved for fuel.

Any ideas?

Originally Posted by JeffinTD

I just started my Syssa for the first time today, and I'm not having the easiest time.

Turns out I had an air leak in the T. Bypassed that, and no bubbles, but it still won't fire by hand, with the mixture screws set as per the directions. Making a very slight change in mixture sometimes has a great effect and sometimes seems to have no effect.

Finally gave up after a muffler bolt fell off.

Anyway, it acts like a fuel related issue. It will act like it is somewhat rich, but shut down like it starved for fuel.

Any ideas?

what size is your fuel tubing?

As for starting it, prime it as the directions say, but be careful, the choke plate has to be in place, or you'll just be sucking air... Get her nice and wet, and she will usually start on the first flip...

1/8 fuel tubing. Lawn boy ashless in non-eth gas.

Pretty sure choke plate is laying flat.

I've gotten it to pop by hand, but to get it to catch seems to take a pretty long hit with an electric starter.

Plug gap is also correct. Carb mount bolts are tight, as are the backplate bolts.

I've had a problem like that with my Syssa. Turned out I wasn't getting the choke plate quite all the way closed. It has to be held against the stop to seal well enough. I also had a problem like this after the magnet fell out of the prop hub, and replaced it with a different magnet that wasn't the same kind. I had to send the motor back to have them replace the hub. Syssa's have an Rcexl ignition that can cause this if you feed it a little too much voltage.

I'm running their IBEC. The choke plate is closing fully.

I just finished reinstalling the engine after pulling it to put the screw that fell out of the muffler back.

Screen in the carb is clear. Fuel filter is clear.

Attempted to start it again. Did the rock it 6 times and see if it pops, nada.

Flipped it till my arm was flipped out, nada. Checked for spark, looked fine. Installed new spark plug (ngk) and hit it with the electric starter, nada.

It drew fuel fine, no bubbles. It has compression. It has spark. It is getting fuel.

I'm pretty new to gas RC, but pretty familiar with small 2 stroke gas engines, and this one has me by the horns...

One thing I forgot to mention. When we first tried to start the engine, it kicked back and spun the prop nut loose a couple of times. I pulled the cowl, and the ignition sensor is not loose or anything. That's when we tried an electric starter and saw air bubbles at the fuel T. (new metal T)

Once that was solved, no more air bubbles, and it hasn't kicked back since.

I'm thinking tomorrow I might try a different fuel, though I can't imagine there is anything wrong with what I'm using (recommended lawn boy for break in, no eth, pass than a week old).

Anybody got any thoughts?

Originally Posted by ghoffman

Mine is really running well these days. I had put it aside for a while, because I was having so much fun with the 68 inch Velox and the beastly DA-60. Now that I am signed up for my first IMAC event, the best plane I own for that is the Syssa powered 78 inch EF Extra. I think that my fuel tank was some of the issues I was having, but now with the Fiji bottle tank, and heavy clunk it is running perfectly, even with 6, single flip starts in a row yesterday. On all of my gassers now, I am running Stihl Motomix which is 100% 92 octane gasoline (no ethanol) with HP Ultra mixed in at 50:1. It is clean, has almost zero odor, and runs so well. It is interesting that Stihl will double their warranty on their power equipment to 4 years if you run it! The downside is it is pricy at $7 per liter, but that works out to about 2 bucks per flying day, so what.

You certainly do not need 92 octane. each to their own though.

Originally Posted by JeffinTD

One thing I forgot to mention. When we first tried to start the engine, it kicked back and spun the prop nut loose a couple of times. I pulled the cowl, and the ignition sensor is not loose or anything. That's when we tried an electric starter and saw air bubbles at the fuel T. (new metal T)

Once that was solved, no more air bubbles, and it hasn't kicked back since.

I'm thinking tomorrow I might try a different fuel, though I can't imagine there is anything wrong with what I'm using (recommended lawn boy for break in, no eth, pass than a week old).

Anybody got any thoughts?

Sounds like the prop hub key sheared which changed the timing. You can check the timing and if it is off, the best thing to do is send it back to Syssa for repair. They don't recommend that the user replace the hub key. (Forget the PM I sent you, the dates are working now.)

If you have a problem with the muffler getting loose, there are two solutions. You can get a new modified one from Syssa, they have a discounted price for engine owners with undamaged mufflers. Also, you can make a mod to yours. I posted the details in my gallery on another forum. If you can't find them and want to do the mod let me know.

My Syssa came with nord-lock washers on the muffler, never came loose. Does sound like a spark timming issue. A problem I've had with mine, is the carb overheating and vapor locking. The muffler and carb are close together; going to try a heat shield between them on the next airplane. Ethanol-free gas also helps with the vapor lock. I use 92 octane, just for the improved shelf life.

Its also possible you are flooding the engine. Take the plug out, if its wet with gas, thats the problem. While the plug is out, spin the prop with throttle wide open to clear it.

Thanks for the input.

Looking at it, spark appears to be about 5 degrees or so advanced.

I know I've flooded it before. This am tried at first to start it without choke. Didn't get anything different.

Just checked output of IBEC- 5.1 v or so.

I guess next I'll do a more accurate check of spark timing than by eyeball.

If that checks out ok, I think I'll be sending it back.

Just the one screw fell out of the muffler. If more do come loose I guess I'll be messing with that, too.

Well, I think Joystick nailed it. Looking into the keyway I thought I could see the slot in the crank, but it looks like magnet meets sensor at least 10 degrees from TDC. Upon probing, I don't think I was really seeing the slot in the crankshaft.

I guess tomorrow morning I'll call and make arrangements to send the engine in.

Really looking forward to maiden on the plane (Rascal 110), but forecast here calls for high wind for the foreseeable future anyway.

Hopefully they have a quick turnaround.



Big thank you to everyone.

I wish you better luck than what others were having with conducting business with Syssa. Several had trouble getting their items and or money back.

Send it in....It will get fixed....And back out to you....
Shouldn't be any issues...
Would be news to me if it was....

I've seen threads about issues, but hope those have been resolved. I sent an e-mail Sunday and haven't gotten a reply, so I'll try calling.