What engine. How does it "die"?

Terry,
A couple things, gasoline has a fairly narrow fuel/air ratio (similar to diesel) like 14/1 vs. methanol at 7/1 ish. First, don't over prop the engine, something around a 12/6 for bench test. Make sure the points are clean, oil free and the batteries are new fresh alkaline cells. Check that all the connections are tight. Last get fresh fuel and oil. One thing you could do is first run it on normal 5% glow fuel with the ignition system (many guys run this all the time). Start with the points retarded almost at top dead center. Once you get it running and a little rich start to advance the points to increase rpm. Once the rpm levels of pull it back just a tad and retune the needle. For running on gasoline (Coleman fuel works well or white gasoline) the needle would be in about half from the glow fuel setting. Start again with the points retarded and adjust as before. Gasoline will not 4-2-4 very well but it should run a little rich but will have a narrow range.

Let us know how it goes.

Best,     DennisT 

Here is a short list from my non-ignition experience.
Some needles are rather coarse in their adjustment.

I know compression can affect needle adjustment, but I am unsure how much it changes sensitivity. 

Adding castor is one way to reduce sensitivity to the needle.  There is less fuel because castor does not burn like fuel. 

Adding castor also effectively increases compression since there is more stuff in the cylinder, which is part of why I am unsure how compression affects needle sensitivity.

Phil

Well, I must report a very red face - mine!  
To prevent anyone new to ignition from following my previous recommendation, I confess that, after a couple months fiddling with an ignition engine, I just discovered that proper fuel/oil ratio is said to be 3:1, not 2:1 as I stated above.
Ref: http://www.antiquemodeler.org/sam_new/p_ignition/assets/ignition_engine_fuel-21st_century.pdf
It doesn't have anything to do with my question about sensitivity but it sure answers some other questions that have popped up during my bench running.

with apologies,

Terry

Right on both accounts, Floyd.
The tank (removed early-on) was the (believed to be trustworthy) source of my choice of 2:1 mix, and it does have a bright blue spark with snap to at least 3/16".

Terry

Although I've run my present Contestor on the bench, I haven't actually flown a Contestor 60 since my first one in the late '40s.  It was in two planes, and I don't remember any needle valve problems.

There are any number of "new" needle valve replacements which will fit.  Try one of the OS units, or a Super Tigre.

Check your spark plug gap.  Try for about 0.012- 0.015"

Floyd

There are some that are more sensitive than others for what ever reason. I have an old Rocket 46 that I have plugged the venture down to very small, and it will still lean out and quit when I raise the front of the test stand even when set quite rich. But my Ohlssons, Super cykes, Spitfires, and Orwicks will all have fairly broad needle settings. My Atwood Super Champion will only run well in a 2 stroke, but is still real broad on the needle setting.

The only thing I can figure is porting and the size of the venture along with compression ratio. You might want to check the size of the venture and maybe sleeve it down a little. I have to plug the venture's on my Spitfires when running fuel to be able to set the needle without it falling out. It works just fine stock on gasoline. The Orwick has the right size venture for the engine and will work well on either fuel. Most of these old engines were set up to get the most power for Free Flight planes, and need a little tinkering to make them work well in control line. I also plug the subpiston induction holes on Super Cyclones, Spitfires, and Orwicks as they run a little steadier for me. Again, your mileage may very.

Oh, one other thing. I do not know what the compression ratio is on your engine, but my Orwick is 10 to1 which is real high for a sparker. The later ones Henry lowered the compression on. I added an extra head gasket to lower it and it starts and runs much better for me with a broader needle setting, and still plenty of power to fly my 64 ounce Taurus on 67' lines. In fact, I had to go to a wood 13-6 prop to slow it down even with the timing retarded to less than half advanced. What a horse.

How many turns open of the NV do you need to run your sparker? On gas/oil, it would probably give such good fuel economy that the NV would be maybe 1 turn open? On alcohol/oil...I'd think it would be close to what a glow engine would need with the same NV assy. and fuel, or a RCH less. What NV assy. are you using?

I don't know squat about the Contester .60, but memory seems like it had a shaft valve with a rear venturi and a weird duct under the case to feed fuel to the shaft?? This seems like it would cause some slow response, much like any RNV/front intake that I've run?? Got a picture?

I rather fancied a Fleetwood .60...pretty much a Schneurle port, near as I could tell. But quality was so rare in those old engines, I let it slide. Heavy darned thing, as well as bulky.    Steve

It may be of interest to someone that I was able to straighten the spraybar collar and rotate the spraybar hole from 6:00 to just out of sight at ~3:15, hole now forward toward cylinder.
Tomorrow I'll see if it makes any difference in needling or overall running.

Terry

Not easier, Phil - it took me maybe 15 mins at no cost, so didn't have to spend $$, go anywhere or wait for delivery, etc.
Running it tomorrow will tell if it was worthwhile, but a replacement NVA is always a possibility.
I have a few NVAs I can try if this doesn't work better, 'though it's more a matter of curiosity at this point since the engine runs well enough in stock configuration.
But better wouldn't hurt. 
FWIW, I didn't measure it but the spraybar hole looks rather large, maybe on account of low fuel flow in it's original location at the bottom of the spraybar.

Terry

Well, I'm very surprised to report that there's no appreciable difference in needle setting with the spraybar hole adjustment from 6:00 to 3:15.
I was expecting a need to turn the needle in somewhat due to lower pressure/less turbulence/better fuel draw at the new position.
Spraybar is .130", venturi is .365" - does that sound about right for a .60?
Terry

Thanks very much, Jim - I'll give that a try then.

Terry

FYI:  Eric Rule (RSM Distribution) is now shipping WILDMAN 60 kits.  I have two, and the kit looks pretty good. All the hard work is already done (laser-cut parts)

Floyd