Recent content by Big_Boat

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    Mercruiser 3.0 12" and 14" flywheel interchangeable

    Hi all, I am finishing rebuilding a 2000 Mercruiser 3.0 that has the newer 14" flywheel and coupler, however the coupler is rusted out. I have 2 spare engines (1995 & 1997) that have the older 12 3/4" flywheel/coupler which are in great shape. Would there be any issue using the older style...
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    Mercury 25XD won't go full throttle.

    So here is the conclusion, I rebuilt the carb and noticed the gaskets were not that fresh. New fuel pump diaphragm and spark plugs and engine runs like a champ, have had it out twice and had zero issues with the motor. Thanks for all the help!
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    Mercury 25XD won't go full throttle.

    Carb kit is on the way. I also got new spark plugs, old ones look fine but who knows how old they are. I could not find NGK BUHW plugs any where which is what is currently installed so I purchased some Champion L76V plugs which should work fine (please correct me if I am wrong). Will update...
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    Mercury 25XD won't go full throttle.

    Here it is (Serial #A194312) it was in the first post, but might be hard to spot since it's a lot of text.
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    Mercury 25XD won't go full throttle.

    I added sea-foam to the tank a few days ago and ran on the muffs to get it into the system. Took the boat out again today, I can get it on plane at about half throttle and get to WOT about 50% of the time. I noticed when throttle is anything over half there is a slight oscillation in the rpm's...
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    Mercury 25XD won't go full throttle.

    I believe it's the gauge, I don't have another one to test the compression. When I was removing the spark plugs I noted that both cylinders were very clean and the cylinder walls were clean with no pitting or scratches. I highly doubt the engine would run as it does right now with bad...
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    Mercury 25XD won't go full throttle.

    Forgot to mention that there was no spark on the 2nd cylinder, which was solved by a new sierra switchbox. So I know that I have spark on both cylinders, carb float was replaced when previous owner rebuilt it (I checked the carb by submerging it in fuel for a while and checking that it still...
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    Mercury 25XD won't go full throttle.

    Hi all, I recently picked up an aluminum boat with a mercury 25XD (Serial #A194312) which would start and run for about 2 seconds then die. Previous owner rebuilt the carb with fresh gaskets, I still decided to take it apart and blow everything out, set idle mixture (2 1/8 turns out) and it ran...
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