Shutdown proceedure for IO520

Aircraft powered airboat discussion.
Lwells
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Re: Shutdown proceedure for IO520

Post by Lwells » Tue Jan 30, 2018 3:03 pm

GMAC 76; You and FOREST GUMP would get along great other than you put things a little milder than Forest. And THATS ALL I GOT TO SAY ABOUT THAT. LOL. I'm glad this thread came up for I cured my problem we talked about but was so happy I forgot to take carburetor apart and check mixture control we talked about so now I got another job. :lol: :stirpot: :banghead:

GMAC 76
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Re: Shutdown proceedure for IO520

Post by GMAC 76 » Tue Jan 30, 2018 4:36 pm

never thought of myself as a forrest gump kinda guy but my wife said "man he nailed that one" .........those little jobs on an airboat will never end larry...lol

J.W.
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Re: Shutdown proceedure for IO520

Post by J.W. » Fri Feb 02, 2018 10:22 am

Same engine io520 . Av gas only or it doesn't leave the yard.Used 93 once to prolong the ride one nite, never again.

Lwells
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Re: Shutdown proceedure for IO520

Post by Lwells » Fri Feb 02, 2018 2:37 pm

I checked the floats in an airplane I had to make sure they were brass and then I started running 50/50 Av gas and medium grade auto fuel back when everyone started trying auto fuel in aircraft and I never had a problem with it but I could tell a slight difference in the power. I went back to pure Av gas in a short time for I have always believe you should stay with Av gas in aircraft engines. What I always noticed about Av gas over auto gas was you could run some Av gas out on your hand or finger and it dissipated almost immediately and left very little smell and was crystal clear and your hand or finger looked clean but pour auto gas on your hand or finger and it stunk and your skin changed colors and it seemed the smell was never going away. Lol

Lwells
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Location: okeechobee

Re: Shutdown proceedure for IO520

Post by Lwells » Fri Feb 02, 2018 2:58 pm

I know we got side tracked from your question of proper shut down so I will get back on track. Best I can remember on aircraft that were fuel injected when they came in and shut down most of them would do a little keep on running for couple of seconds and best I remember it was mostly fuel injected engines and seemed like they were terrible about restarting if they only set a short time, correct me if I'm wrong GMAC 76. I DONT KNOW WHETHER IT WAS NATURE OF THE BEAST OR WHAT. I had a mechanic tell me that only way he could cure the shut down problem was that people he knew he would set the idle lower than normal so that when the throttle was pushed all the way in that it might die or barely run and he would tell them to never push it all the way in unless they were on the ground or getting ready to shut it down. He said hot aircraft engines need very little fuel to diesel off compression on shutdown but that if the throttle has pretty much shut the engine down then most times it won't diesel. Now everything I just said may be wrong for I'm telling it best I remember and maybe it will help if I'm correct.

PanJH
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Re: Shutdown proceedure for IO520

Post by PanJH » Sun Feb 04, 2018 8:08 am

GMAC 76 wrote:I honestly and truly love all the guys that start their engines on both mags and use only the mags to shut'em down....it keeps my little mag repair shop busy...lol
I shut down by using the mixture control ... but explain why using both mags to start and shutting down with the mags shortens their life.... thx

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Re: Shutdown proceedure for IO520

Post by GMAC 76 » Sun Feb 04, 2018 9:57 am

starting with both and shutting down with mags heightens the chance of engine kickback and bad things can happen when it kicks back...it doesn't really shorten the life of the mag it just kills it outright...shutting down with the rich and lean lever or the idle shut off lever (5AA CARB) is the safest way to shut down an aircraft engine imo

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