Cold And Plug Fouling

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GaryRR
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Cold And Plug Fouling

Post by GaryRR »

Is it just me or do colder temperatures make plug fouling more likely? I base at KSEG in Pennsylvania 18 miles from home and when Live weather temperatures are 32f and less the plug fouling is a near given.

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Oracle427
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Re: Cold And Plug Fouling

Post by Oracle427 »

Let the engine warm up more before running up. You might just be dealing with a still cold engine and the oil temp should be climbing up closer to the green arc. To cut down on warn up time use the engine preheater option.

That said I'm not sure if you are leaning as aggressively as everyone recommended on your other thread. You need to pull that mixture waaaay back to lean correctly for taxi and warm up.

I fly in the same climate in the sim with no issues.

Are you preheating? Are you leaning to the point of engine roughness at 1000-1200 rpm and then enriching just enough to smooth out the engine for taxi and warm up? Are you letting the oil temp come up to the green arc prior to run up?

To be honest I find the intensity of symptoms related to plug fouling and engine roughness due to a cold engine to be exaggerated in the A2A sim. However, the fact that these symptoms can be totally avoided by following proper technique is a net positive in my book.

As a former owner/operator of a fleet of three Cessna aircraft I used to see the results of poor leaving technique when the aircraft went in for scheduled maintenance. The spark plugs were extremely dirty with lots of lead deposits all over the insulation requiring a lot of extra effort to clean using small picks to fish out the larger pieces. You could feel a little difference in the engines right after the plugs were cleaned up.
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

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Oracle427
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Re: Cold And Plug Fouling

Post by Oracle427 »

Example of a good plug:
http://cdn.shopify.com/s/files/1/0970/7 ... 1568292542

Example of a seriously fouled up plug (this doesn't happen in a few minutes):
http://www.guysaircraft.com/pics/aviati ... fouled.jpg
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

GaryRR
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Re: Cold And Plug Fouling

Post by GaryRR »

I do lean yes. Way back. I also keep my rpm and map way back as well to minimize forward drifting with the parking brake set. In most sim aircraft that don't have correct engine physics modelled that is what I had been doing to minimize drift while I set up my flight plan etc. It helps but I know it isn't real world done because of plug fouling. I perceive I need to keep my rpm
up and my MAP up to maintain that while leaning as much as smooth engine idle will allow. I fear running battery down setting up my GTN before engine start. I do use engine heater.
That darn ground drift is annoying. Worse in some sims than in others.

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Oracle427
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Re: Cold And Plug Fouling

Post by Oracle427 »

The ground drift is a universal issue with the sim engine. There is unfortunately no way to stop this 100%.

Turning on and configuring the avionics prior to engine start is not normal practice and doesn't make sense as you need to turn them off for engine start. You would end up losing all your work. If you are trying to follow real world procedures this is just something to make note of, otherwise no big deal. Running the avionics on the ground with the engine off would drain the battery very quickly in real life.

You do need to keep RPMs up at 1000-1200 room or the plugs will foul.
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

GaryRR
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Re: Cold And Plug Fouling

Post by GaryRR »

I ran a flight PHL to MDT. Followed the numbers. Ran well until I had to do a go around Rwy 31 due to a pokey AI skyhawk. 172 at HIA. Guess it happens. Anyway I kind of acted hastily with my power. When I parked and checked SOME plugs were fouled. I assume it happened during go around or taxi. I will perfect it. Ir spring and summer temperatures will help. 35 when I landed.

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Oracle427
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Re: Cold And Plug Fouling

Post by Oracle427 »

Do you lean while in cruise and if so how do you go about it?

By the book once you establish cruise power settings (RPM and MAP) you will then lean to peak EGT and then enrichen to 50 ROP. If you run very rich while in cruise, you may end up fouling the plugs over time.

If the mechanic is complaining about fouled plugs but everything else seems OK and your engine is getting smooth run-ups then I wouldn't get too excited either. It's not unusual to see that message even if the aircraft isn't showing any major issues.

With leaded fuels the plugs will always get some fouling.
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

GaryRR
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Re: Cold And Plug Fouling

Post by GaryRR »

I lean during cruise. I set my map and ROM up to cruise about 1t8 indicated. Map usually about 24 pr 25 and RPM about 2500. I pull back my mix until the RPM start to fluctuate a little then I rich it up a little until it smooths. I'm writing off my phone outside of work so I can't be precise about my settings without being in the Bonanza. I will write next time I'm in the Bonanza.
I have the Skylane also and it's a bit more forgiving in power. I suppose the difference is the same in the real planes. The V-tail seems generally more frisky. I love them both. Cessna less work though.

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Oracle427
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Re: Cold And Plug Fouling

Post by Oracle427 »

That's good enough for me. So is the engine running through during run up while doing mag checks or are you just seeing the notes in the maintenance hangar?
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

GaryRR
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Re: Cold And Plug Fouling

Post by GaryRR »

Engine is running. If there is any fouling I can tell when I do run up and or cycle the prop rpm. I DO Want to fly it as real. I have all the peripherals to do so.

GaryRR
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Posts: 353
Joined: 26 Dec 2020, 22:32
Location: KSEG Selinsgrove, PA

Re: Cold And Plug Fouling

Post by GaryRR »

Yes. I checked the panel screenie. At cruise my MAP typically at 24. My RPM generally at 2500. And my mix I can run at 14. Yields 158 knot. I don't typically see evidence of fouling in flight.

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