engine gets to 2000 rpm then over rev's.

outbound

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Hi, <br />I have a 1995 454 mercruiser, bravo3 I/O, Runs great till yesterday. It can't get out of the hole or above 2000rpm with out overreving and falling off step(basically losing thrust but not horsepower) Is it the clutch assembly in the upper drive housing slipping? I know its not the props because there is no rubber hub in props on a Bravo3 counter rotating lower unit.<br /> A guy from mercurymarine.com told me it was the upper coupler. Whatever the heck that is that, cause I can't find a picture or description of anything called a coupler in the book. <br /><br />So far I have tried the following: <br />-adjusted shift linkage both ways. <br />-removed both props-no apparent damage.<br />Help!!!<br /> :confused:
 

snapperbait

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Re: engine gets to 2000 rpm then over rev's.

The guy at Merc is on the right track...<br />
MER18311A17_thumb.jpg
<br />This is a coupler.. It's bolted to the engine's flywheeel... This is not necessarily the correct one for your Bravo3, but basicly the same...
 

outbound

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Re: engine gets to 2000 rpm then over rev's.

Thanks Snapper,<br /> How can I rule out either of the two then, the cluch or the coupler? The coupler would be alot easier to get to since I don't have the special tools to get the outdrive apart and together again. And I have already had the engine out.<br />Thanks
 

Bondo

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Re: engine gets to 2000 rpm then over rev's.

If the outdrive is Off, What does the Input shaft look like ???? any Metal Shavings ??? the coupler is What it Slips Into..... With a bright light, You Maybe able to look up into it.....
 

outbound

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Re: engine gets to 2000 rpm then over rev's.

Thanks for the reply Bondo,<br />I haven't had a chance to take it off yet but will do asap and let you know what I find. I've done some more research and have discovered that this is a pretty common problem. I really hope that it is infact the coupler and not the clutch in the o/d.<br />Thanks Troy :rolleyes:
 

Bondo

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Re: engine gets to 2000 rpm then over rev's.

outbound, <br />you say "And I have already had the engine out."<br />Did you realign the gimbal bearing at that time ????<br />If Not, That's Why your Coupler is Shot....<br /><br />Either way, the outdrive Has to come Off.... You May find Filings, or rubber dust....
 
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