Having major issues with my tower hobbies .46 glow engine. The thing dies on me as soon as I remove the glow starter. I can't seem to get the needle valve setting right. I tried just about every possible combination. It is so frustrating. On top of that. I just sent back my OS 46AX engine because it was having the same problem. I'm screwed. I hope they send me a new engine. I'm determined to get the tower hobbies engine running. Today I will mess around with it some more.

I hope you didn't move the low speed needle too much?
Tune with the glow attached for now.
At full throttle pinch the fuel line going to the carb (be carefull of the prop) if it increases rpms before dying it is rich if it just dies it is lean. Find the point where you are right in the middle and turn the high speed needle about 1/4 turn CCW to run just slightly rich.
Repeat the proccess for idle with the low speed needle, turn the engine off when adjusting the low speed needle.
You should now be able to run without the glow ignitor, adjust again.
This is all assuming you have the plumbing hooked up correctly and the glow plug is good.
A better bet is to find an experienced pilot at a local club to help you.

Some things to check to avoid going crazy are:
No air leaks... look very close including IN the tank. carb parts junctions, back plate and head. ANY air bubbles in the line is a clue. O-ring on base of carb and neddle valve
tank at proper elevation in relation to the carb
FRESH FUEL...spent half a day cussing a perfectly good engine[:@]
good plug but be aware plugs get blamed for almost ALL of the above a lot.

Most likly too rich.
I read some articles on this perticular engine. It seem that some people was having problems with this engine
and others didn't.
Tunning issue or consistancy operations. But this engine has very good power compair to other .46.

It boggled my mind. After all, it's just a 2 stroke single cylinder nitro engine. There's not that much to it.
What in the world was causing so much headaches for some.
Having confident ...I even purchased 2 of them.

Anyway, if it was tunning issues. I took the fuel intake system apart.
I un screwed the fuel line fitting barbs. Right off the bat there it was.
Some of the barbs had burrs from the chrome plating. I de -burred them.
Both of the engines runs perfect

OK... thanks for all good tips and advise. Today I replaced the glow plug (I knew the old one was fine - I just wanted to be certain) with an O.S. A3 glow plug. Then I filled the tank with new fuel. I set the HS valve to 2 turns out and the LS valve to 1 1/4 turns out. I started the engine and left the glow driver connected for about a minute or so. Then I disconnected the glow driver and the engine seemed better. I ran it like this for few minutes to make sure it won't stall. I had the adjust the HS needle valve when I had the engine running at full throttle... it's set at about 1 3/4 turns out. I have a feeling the the old fuel was bad because the new fuel seemed to help the engine to run better. I will work on it some more to make sure the needle settings are where they need to be.

Thanks

Do as said above with pinching the fuel line. Otherwise you don't know whether the low mix is to rich or to lean or right on. Should just pick up a bit of speed before it quits.

Well I went to our field today and had better luck with the Tower Hobbies .46 engine. I was able to get couple flights in. The first time I tried to take off, I hit some cross winds and the Alpha did a nose dive into the ground. I destroyed the prop and had to glue a piece of wood on top of the fuse, where the leading edge of the wing rests against. Other than that, the plane was ok. The engine shifted a little so I had to realign it back in place. It happened right as soon as I got off the ground a few feet so the damage was minimal. I'm glad I didn't destroy it completely. That would have sucked. Also the carb barrel got some dirt around it so I had to take it out and clean it real quick. I plan on going back tomorrow evening to fly some more. It's so much fun. I just need to watch out for those cross winds. Thanks to all of you for your help. Here is a pic of what's left of the prop:

BTW: The A3 is NOT a good plug for the Tower Hobbies .46 engines and above.

The T.H. engines come with and need a "long" plug, such as those used for four strokers.

Also be sure to use a heavier prop, such as an APC. Many engines work and idle much better with the heavier props. This is one of the reasons for the "inconsistencies" between people purchasing these engines.

Keep a long plug on it, with the proper APC prop, and it's an easier to tune, more reliable engine. After it has been run for a while ( 2-3 gallons ) you can usually switch to the lighter props.

What glow plug should I use with the TH .46 engine?

Most "long" plugs work well.

I've seen no advantage to the long plugs with idle bars, even when the engine is mounted inverted.

For a comparison:



Caption: From left to right: Stock Evolution 1.00NX 2 Stroke Glow Plug O.S. "F" 4 Stroke Glow Plug Stock SuperTigre .75 2 Stroke Glow Plug O.S. A3 2 Stroke Glow Plug

Just because the head will accept a long plug doesn't mean it has to have one. I assume the manual tells you what plug to use.

It has to have one in this case.

The T.H. engines come with "long" plugs installed.

It's what Tower, GMS and Supertigre supply with their engines too, out of the box.

The manuals specify the "superplugs" which are also longed nosed.