1989 Merc 7.4's RPM's

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Samuel
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Re: 1989 Merc 7.4's RPM's

Post by Samuel »

I didn't realize the lake was that small.
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Re: 1989 Merc 7.4's RPM's

Post by mjk1040 »

I saw a survey like that here in our Marina, and half way in at WOT, Poof! And blue smoke everywhere! And OH S**T! They didn't notice it for what seemed quite a while. Then lip her back in on one engine. Anyone can be a surveyor, but some should not!
Mike :down:
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tonyiiiafl
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Re: 1989 Merc 7.4's RPM's

Post by tonyiiiafl »

I am a diesel mechanic and bought a gas 390 CPMY. I just don't do the hours per year to merit the premium price of a diesel. I also have 454/7.4 Blue Water Mercs, I hit 3800 WOT and was happy with that. usually run at 2800 to 3000 19 kts. Plenty fast for a boat this size!
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sep4086
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Re: 1989 Merc 7.4's RPM's

Post by sep4086 »

The boat might have the wrong size props.
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Grady2011
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Re: 1989 Merc 7.4's RPM's

Post by Grady2011 »

So I got her back out on the water and eased up to WOT to see what it would do again. Last time I did that must have cleaned some of the junk off of the bottom and cleaned up the carbs a little. Lol. She would hit all around 4300 rpms. I didn't keep it WOT very long but it did make me feel better! I like cruising around 2500rpms.
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