Detonation
Moderators: Rick, Lance Murray
- astaib
- 5 Diamonds Member
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- First Name: Arnaud
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Detonation
Hello,
Short question because yesterday on a hot start (at fuel station) I heard a detonation from my engine.
How can I avoid this?
Is it due to hot start?
What do I risk?
Anything to know?
Thank you!!!
Arnaud.
Short question because yesterday on a hot start (at fuel station) I heard a detonation from my engine.
How can I avoid this?
Is it due to hot start?
What do I risk?
Anything to know?
Thank you!!!
Arnaud.
Arnaud
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
- Rich
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Re: Detonation
Do you really mean detonation or what we often misidentify as a "backfire"? By that I mean air/fuel mixture igniting in the exhaust system.
The latter happens when a cylinder fuel/air charge fails to ignite in the compression cycle, is pumped out in the exhaust stroke and gets ignited by the hot exhaust from the next cylinder. This can happen, for example, if you accidentally switch mags to "off" and back on during a runup. But an overly rich mixture at start could do this also.
The latter happens when a cylinder fuel/air charge fails to ignite in the compression cycle, is pumped out in the exhaust stroke and gets ignited by the hot exhaust from the next cylinder. This can happen, for example, if you accidentally switch mags to "off" and back on during a runup. But an overly rich mixture at start could do this also.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
- Steve
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Re: Detonation
That is what I thought - a "Backfire". Interestingly, I've never had one in my DA40 in almost 19 years of operation. Plenty of other airplanes at my home field have them, though.
- astaib
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Re: Detonation
OK, thanks.
But can the backfire be as harmfull for the riser and mufflere as when you accidentally switch of the mags during runup?
How to avoid backfire during hot start?
Arnaud.
But can the backfire be as harmfull for the riser and mufflere as when you accidentally switch of the mags during runup?
How to avoid backfire during hot start?
Arnaud.
Arnaud
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
- AndrewM
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Re: Detonation
I have read that a backfire can cause cracks in the exhaust and therefore possible carbon monoxide issue. Something to keep in mind for a check at next annual and be careful to ensure you have the CO2 monitor going and potentially a backup.
- astaib
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Re: Detonation
This is exactly my question: the cracks on the exaust system.
How to prevent not to make backfire on a hot startup?
Arnaud.
Arnaud
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
- astaib
- 5 Diamonds Member
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- Joined: Mon Feb 26, 2018 9:00 pm
- First Name: Arnaud
- Aircraft Type: DA40
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Re: Detonation
me too, it only happened rarely, but I don't like to hear this and to risk to damage the exaust system.
Arnaud.
Arnaud.
Arnaud
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
- Rich
- 5 Diamonds Member
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- First Name: Rich
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Re: Detonation
I have no magic cure for this. My hot/warm starts are typically to start cranking at full lean mixture and after about a second slowly advance the mixture. Somewhere in there it starts. Works every time.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
- astaib
- 5 Diamonds Member
- Posts: 616
- Joined: Mon Feb 26, 2018 9:00 pm
- First Name: Arnaud
- Aircraft Type: DA40
- Aircraft Registration: FGNJX
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Re: Detonation
This is what I do.
In WOT position.
When it fires, from WOT to idle quickly
In WOT position.
When it fires, from WOT to idle quickly
Arnaud
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b
DA40 Star 180 / 40.026 / 2001
Wingtip, landing and taxing LED (Whelen)
Skitube
GNS430 NON-WAAS
Steam gauges
Non certified ADS-b