www.iFourWinns.com

After overheating my engine trying to get off a sandbar (stupid) my maximum WOT dropped to 4000 RPM's. Immediately afterwards I changed out my exhaust manifolds and risers only because of their age. Other than the loss of RPM's at WOT the engine does start and run good/smooth. Prior to writing this message I did check the butterfly's in the carburetor to insure that they are fully opened at max throttle. They were. I then attached a vacuum gauge to the carb to check the vacuum at various RPM's. 800-900rpm - 16in HG, 2000rpm - 20in HG and 3000rpm - 14in HG. At all rpm's gauge fluctuation was + or - 1/2in HG. Short of checking the engine timing I have run out of troubleshooting options and could sure use a little help. Any ideas?

Any prop damage?

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Mike
2005 Four Winns 230/240
VP 5.7GXi/DP
1998 F-150 XLT
Boat Pic

No prop damage. As a matter of fact after my accident a friend gave me a SS 14 1/4 X 23 prop that I had re-hubed and re-pitched to 21. Only Lost about one or 200 rpm's compared to the Aluminum prop. When replacing both manifolds I performed a compression check and if I recall, only #1 cylinder was a tad low at about 125lbs. I'm beginning to wonder if it's something in the ignition system that just happened to go bad at the wrong time? I'm lost for answers.

Something stuck to the hull? Hull damage?

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2003 FW 170 Freedom 4.3 GL/SX

I wish it was that easy. No damage to the hull as far as I can see.