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Engine basics => Engine set up tips => Topic started by: Tim Wescott on July 12, 2018, 09:09:20 PM
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I'm looking for suggestions to look for.
I have a 40FP on a Ringmaster, throttled for NW Sport 40 Carrier. It'll go like gangbusters for two or three laps, then suddenly die. It doesn't seem to matter what throttle setting it's at, from full to extra slow (but not hanging) flight. It doesn't seem to matter if I'm launching just a bit off full lean scream or quite rich.
The glow plug appears good, but I haven't tried replacing it (yet). The clunk is clunking. I can fly, restart without refueling, and it'll go for 2-3 laps then die just the same. The plane is landing with fuel in the feed tube, and at one point it quit in the ground with fuel in the feed tube.
When it cuts out it goes straight from full on to stopped -- no lean scream, no rich blubbering, no misfires; it just stops.
I'm mystified -- anyone have any suggestions?
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Tim,
A couple of thoughts--mostly questions:
Will it run on the ground continuously or does it have the same problem? (Would tend to rule out plug issues if no problems. I'd still check to see if the element is distorted.)
Did you run it on the ground with the outboard wingtip down about 20 degrees down? Still runs continuously? This would get the fuel head about right, and move the clunk to a flight-like position.
Is the tank flexing enough to allow the suction of the engine to block off the pickup (clunk)? This would be less likely if you were running tank pressure. Similarly, is the centrifugal load of the fuel due to flight doing the same?
Do you have excessively long fuel or vent lines that will flex in flight and pinch off?
Do you run a filter on this plane? Is it clear?
Are you sure you are running from the pickup tube and not the vent tube?
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My OS35s did this exact thing last month. Turned out to be bad fuel. I have also had this happen once and it was a cracked filament in the glow plug. Good luck..... "I hate it when she does that"
Ken
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I Dallas a few years ago I had the same problem, changed the plug, and no more problems.. I'd try that first.. Good luck...
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I Dallas a few years ago I had the same problem, changed the plug, and no more problems.. I'd try that first.. Good luck...
That's what I was going to try first if no one answered my thread. I guess it's still my first thing to try...
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Secondly, I'd try another tank just to eliminate that possibility. 8)
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Danny Dirt had a similar problem with his usually reliable ARF Streak / FP .20. He'd stored it nose down, and found that the clunk tube was stuck in the front of the tank. A bad or loose glowplug could also be the problem. ??? Steve
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Danny Dirt had a similar problem with his usually reliable ARF Streak / FP .20. He'd stored it nose down, and found that the clunk tube was stuck in the front of the tank. A bad or loose glowplug could also be the problem. ??? Steve
I double-checked the clunk -- even pulled the tank apart to be sure. I don't usually have the clunk move to the front of the tank in storage unless I "stored" it a couple of inches nose-first in the dirt. I also had the glow plug out and back in.
I'm thinking bad glow plug. I need to get out with that plane and play.