Whistle at idle and backfire

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BHB
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Whistle at idle and backfire

Postby BHB » Sat May 05, 2012 4:55 pm

I have a 180 lycoming with an ha-6 carb. Just had the carb rebuilt and new intake and exhaust gaskets installed. It's making a whistling sound at idle and backfiring when I let off on it. Also it falls on its face when you hit the throttle even just easing into it. I'm thinking probably an intake or exhaust leak? It's backfiring through the exhaust. Any help would be greatly appreciated. Thanks.
NO FARMS, NO FOOD!

pirate
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Re: Whistle at idle and backfire

Postby pirate » Sat May 05, 2012 5:24 pm

Compromise is failure on the installment plan.

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swamp runner
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Re: Whistle at idle and backfire

Postby swamp runner » Sat May 05, 2012 6:51 pm

how did it run before ? sounds like the carb wasnt done right ,the excelorator pump not working . make sure that the exhaust nut didnt run out of threads before it snuged up against the header , you might need to put a washer .
12' HAMANT ULTRALIGHT - 180 LYCOMING - 68" CYPRESS SERIES

junebug
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Re: Whistle at idle and backfire

Postby junebug » Sat May 05, 2012 8:16 pm

:rebel: Intake Vacuum leak..Spray some starting fluid around the tubes it will let you know which one is sucking air..

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hmgm123
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Re: Whistle at idle and backfire

Postby hmgm123 » Sat May 05, 2012 10:34 pm

junebug wrote::rebel: Intake Vacuum leak..Spray some starting fluid around the tubes it will let you know which one is sucking air..


BINGO!


woods and water
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Re: Whistle at idle and backfire

Postby woods and water » Sun May 06, 2012 1:08 pm

Intake leak check gaskets and hoses

BHB
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Re: Whistle at idle and backfire

Postby BHB » Sun May 06, 2012 4:07 pm

Thanks for the quick replys. I tightened up the exhaust and and intake and the whistle stopped but one of the headers studs won't tighten up seems to be rung off inside the jug it just spins. Is there an easy way to fix this problem?
NO FARMS, NO FOOD!

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swamp runner
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Re: Whistle at idle and backfire

Postby swamp runner » Sun May 06, 2012 8:22 pm

go to ace and get a helicoil kit . that will fix you right up :thumbleft:
12' HAMANT ULTRALIGHT - 180 LYCOMING - 68" CYPRESS SERIES

blown480
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Re: Whistle at idle and backfire

Postby blown480 » Sun May 06, 2012 8:27 pm

5/16 -18 helicoil kit will fix you up,

BHB
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Re: Whistle at idle and backfire

Postby BHB » Sun May 06, 2012 9:08 pm

Thanks everyone really appreciate it
NO FARMS, NO FOOD!

BHB
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Re: Whistle at idle and backfire

Postby BHB » Mon May 07, 2012 2:22 pm

Well I ran the boat and after having the carb Rebuilt I have lost almost 500 rpm. Was turning 3k now 2500. The more money I spend on this boat the worse it gets. Who's the best around Oviedo that could work on this thing for me. Much appreciated.
NO FARMS, NO FOOD!

rhodes
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Re: Whistle at idle and backfire

Postby rhodes » Mon May 07, 2012 6:21 pm

Check to see if carb. is going wide open.

junebug
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Re: Whistle at idle and backfire

Postby junebug » Mon May 07, 2012 7:44 pm

rhodes wrote:Check to see if carb. is going wide open.



:rebel: Exactly..When carb was reinstalled the Throttle cable probably was'nt properly adjusted..

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Chipper
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Re: Whistle at idle and backfire

Postby Chipper » Wed May 09, 2012 1:00 pm

Danny Oliver. Get ahold of diamond back airboats. They know how to get ahold of him. Best of luck :salute:
2007 HillBilly Bears 13' U/L ALUMITECH,3/8 Blue Steel Poly, 4.3 Vortec, BRODIX heads, 2.38-1 Stingergear box, 80" Sensenich prop,MSD, Quick Fuel carb that gets the job done

BHB
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Re: Whistle at idle and backfire

Postby BHB » Wed May 09, 2012 3:39 pm

Danny's helped me out before, great guy, just to far away
NO FARMS, NO FOOD!


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