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Old 09-25-2011 | 01:44 PM
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Default 496 Mag Help

Need some help here this is my first 496 Mag I have always had 502's in the past. Put the new boat (03 288 Sunsation MCOB) in the water this weekend and boat ran great. Prior to the purchase I had a full survey, compression & Leak down and had the drive pulled for inspection. All numbers came back well withing the parameters posted by Raylar on an earlier post. also did a sea trial and run the bot all the way to WOT with noo issues. Boat has 223 hours. I was able to open it up a few times yesterday and running a 24p Bravo 1 hit 4400rpm and 60 on the speedo (not GPS) I know to expect about 62 out of the boat, I was not trimmed to the sweetspot so I think the other 400 or so rpm will come. also should mention i had four adults and abotu 80 gallons of fuel on board. Question is at about 3800 - 4400 rpm i can hear a loud popping nosie from the exhaust, (sounds like port side) sounds last plastic flapping at high speed or a series of small firecrackers. The engine pulls strong at all rpm's and the tach is steady so I am having a hard time with the idea that its missing out. Anyone have any ideas??
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Old 09-26-2011 | 08:07 AM
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Given the fact that you just had a compression test done and you are down 400 RPM, I would say they may have cracked a plug when removing/reinstalling them.
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Old 09-26-2011 | 11:09 AM
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Originally Posted by Knot 4 Me
Given the fact that you just had a compression test done and you are down 400 RPM, I would say they may have cracked a plug when removing/reinstalling them.
Thanks....that or a loose or bad plug wire seems to be the general consensus I will pick up a set and get them replaced.
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Old 09-26-2011 | 01:04 PM
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It is very easy to not get a wire reseated properly too so one may have fallen off. I had this happen on my 496. Number 2 wire was laying in the bilge.
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Old 10-09-2011 | 06:38 PM
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Fixed It!!

Replaced the plugs today and I either had a bad plug or loose plug wire the boat ran great. Trimmed out 4650-4700 and 65 on the wish-o-meter. It ran perfect all day long!
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Old 10-09-2011 | 07:08 PM
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Originally Posted by bigredbaja
Replaced the plugs today and I either had a bad plug or loose plug wire the boat ran great. Trimmed out 4650-4700 and 65 on the wish-o-meter. It ran perfect all day long!
Great news!!
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