FlyBoyDavid

Hi all! I'm new to Glow engines. My first is a Tower Hobbies .61. I can't join the local club until next month. So I figured I come here for some advice. Basically with the engine set at factory settings it won't reach full throttle. It dies at about 75% throttle. Just seems to choke out and die. I've noticed that the muffler will have a bit of fuel in it when I get done fiddling for the day. Which leaves me to believe that it is way too rich. Is this correct?

The directions state to turn the needle valve out 4.5 turns. Then lean it untill you hear the engine change pitch and run smooth(or something to that nature). Then pinch the line. If it speeds up lean it a little more. And do this untill it doesn't speed up. After that you start dialing in the idle needle.

Should I lean it out untill I can achieve full throttle? Then go from there?

Thanks,
Dave

AlStack

My Feedback: (1)

I have the same engine. Just continure to run it sloppy rich for at least two fuel tanks. Let it break in BEFORE you lean it out to much. If you run it to lean you will kill it.

Hook up with someone from your field for more advice. Onece that engine is broken in, it will be strong and last you a long time.

Just my 2 cents worth.

Al

DBCherry

My Feedback: (4)

Dave,
Welcome.

Al gave it to you in a nutshell. I'll just stretch it out a bit.

Lean it out enough to get it to run at full throttle. Run out most of another tank (at least) like that. Then lean it more until it breaks into a "2 cycle" run. Leave it for a few seconds (10 - 20), then richen it back to a 4 cycle run.

Once you've gone back and forth between 2 and 4 cycling for a while, you can let it run longer in the 2 cycle mode. I'd run it 2 cycling for 2 or 3 minutes, then shut it down and let it cool off for 5 to 10 minutes. Restart and run it again for 2 to 3.

All of this breaking in should be done at full throttle by the way. (But throttling back every once in a while won't hurt anything.)

I'd do the above through 3 to 4 tanks. Then lean it out enough to fly with it, but keep it on the rich side for the next few tanks. (I always run my engines rich enough so that they "burble" a little when throttle's backed off, and my engines last forever.)

Good Luck,
Dennis-

CHOCOFAN

My Tower .46 took more than 3 or 4 tank's of fuel it took something close to 9 tank's of fuel.also did the 30 sec. interval for 5 pinch thing, and also running it on the rich side till I see a nice trail of smoke behind my SE, got graet power I'd say more than a GMS .47. It's funny I had to buy 3 of tower's engine's to finally get to understand them but once broken in they really go. Had my tower hobbies .46 on an uproar & pulled it way hard ,so hard it ripped off the left wing in a snap roll, thinking of getting there .75 for a King Kobra.

chris-fla

My Feedback: (2)

Make sure the engine is broken in properly which would entail running very rich 2-stroke for a few tanks. Make sure it isn't too rich since you need the ABC engine to reach nomal operating temperatures to break in properly. 4.5 turns out on the high end is a bit much, I find that I start at 3 turns out, my engine won't even start at 4.5 turns out, so try that first.

Chris

FlyBoyDavid

Thanks for all of your help. I'm just going to wait untill I get to the club field. Sometime in the next 2 weeks. And seek some on site advice/help. All of my R/C background is in electrics. That and I can't really run it at full throttle at my house. I'm sure that wouldn't sit very well with the neighbors. Thanks again.

Dave

DBCherry

My Feedback: (4)

WAIT! If this is an ABC engine, ignore EVERYTHING that's been said above!

The very last thing you want to do with an ABC engine is to run it rich. You'll destroy it pretty quickly.

ABC engines have a very tight piston to sleeve fit at the top of the stroke. This is where they get their compression.

"Breaking in" an engine is done to seat the parts so that they fit properly. With a standard engine, rich keeps the parts cooler so that they seat without wearing excessively.

Well in an ABC engine the piston and sleeve expand at different rates, so if you run them rich (they stay cooler) the piston expands but the sleeve doesn't. Therefore the sleeve wears too much, and when you do lean it out and run at operating temperatures a good deal of your compression will be gone. Not a good thing.

To break in an ABC engine you want to run it at operating temperatures (fairly lean) right from the start. But, you only run it for a minute or two, then shut it down and let it cool down. You continue doing this, and after a couple of tanks you increase the run time between cool-downs.
Dennis-

Blackie

Dennis, I was just about to say that I am on my second warrenty replacement TH ABC .75. The reason I had to send my old one in was due to the fact I was running it to lean. On this second go around I am going to stay with the smoke trail and keep it rich.

I am not sure if you are just speaking of the break in period or through its life duration of keeping it lean.

Dave, here is what I would suggest, contact Tower Hobbies tech support and ask them this question. Run the engine as they instruct you to do.

Blackie