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Boat Idles Weird?

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Old 07-11-2011, 01:51 PM
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Default Boat Idles Weird?

What cause the engine to idle up and down with in 200 or 300 rpms? While just floating.. any info would be great. Thanks mike
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Old 07-11-2011, 03:25 PM
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Blowers?
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Old 07-11-2011, 03:53 PM
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most likely a vacuum leak...
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Old 07-11-2011, 04:13 PM
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Possible Idle Air Control (IAC) valve defective
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Old 07-11-2011, 04:29 PM
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If we just knew what engine.... Carb or injection...IAC's are PITA's sometimes.. so are vacuum leaks... if a carbed engine the leak can be in the carb too... a real PITA to find out.
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Old 07-11-2011, 07:19 PM
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Mine did that when I had a jacked up map sensor on it. 525
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Old 07-11-2011, 10:54 PM
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its a 525 blower with 2 800s on it
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Old 07-12-2011, 12:21 AM
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Quote:
Originally Posted by rollnhrd View Post
its a 525 blower with 2 800s on it
its called blower surge,,normal if you have alot of boost
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Old 07-12-2011, 12:35 AM
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Quote:
Originally Posted by mrfixxall View Post
its called blower surge,,normal if you have alot of boost
Yup and it sounds cool leave it alone.
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Old 07-12-2011, 02:27 AM
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The surge is caused by each revolution of the blower. Sometimes it can be reduced or eliminated with carb air bleed adjustments.
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