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Old 07-15-2013, 04:27 PM   #11
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JrJ01, best of luck and report back on the findings from the shop.
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Old 07-16-2013, 05:52 AM   #12
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Hey Jr,
I have a 1994 2700 SCR with the 7.4L and bravo 2. My boat with full water and fuel and about 4 people on board running a 19" pitch cruises around 3300 RPM at about 16 knots (18mph). WOT is around 4600 RPM and hits about 30 knots (34mph).
I forget my readings with the 21" pitch prop but top RMPs were only about 4200

Hope that helps,
- Joe
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Old 07-19-2013, 02:01 PM   #13
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Took the mechanic out on it yesterday.. gonna pull it out this weekend it looks like.. the engine is performing
well. The timing is on.. compression good.. carb could use an overhaul but did a good cleaning while there.. so boat is running as it should and the
engine is strong.. so we get it out.. and it dogs as usual, he's telling me to trim it out.. I tell him I am.. its all it does.. so he then says this
boat feels like its pulling an anchor behind it.. so I am not halucinating.. says it has to be the outdrive.. we know its not the prop both are reconditioned..
says the lower unit may not be the right gear ratio for the boat if it was ever changed out,
does this sound reasonable? trying to find out what gear ratio this boat should be now.. engine OK166682 drive OK184680
calling around today
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Old 07-19-2013, 03:01 PM   #14
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I think the gear ratio for our setup is 2:1.
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Old 07-19-2013, 08:24 PM   #15
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According to maxumcustomercare.com your 2 7.4l engine options for that boat were:
ET6 OPT. 300 M C/B2 (7.4L) 1.81:1
or EP9 OPT. 300 M C/2 (7.4L) 2:1

I know my sport boat is a different animal, but the engine and outdrive numbers match on mine. Any chance the previous owner cleaned off the original leg and replaced it with the wrong one? The mechanic's idea has great potential.
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Old 07-20-2013, 03:29 PM   #16
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Hello thanks for letting me know!! still not sure what boat I have but I think its the 1.81 ratio. is there somewhere I can look on the boat to tell?
I am thinking that yes at some point the lower drive was replaced with the wrong lower.. so, I bought a full 1.81 geared upper and lower drive off my local
craigslist today.. gonna see if that works out tomorrow. I just hope mine is not the 2.1 engine..
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Old 07-20-2013, 04:14 PM   #17
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Jr, buying another drive is a costly experiment. The ration of 2:1 means that for every 2 revolutions of the drive shaft (input to out drive) the prop shaft will rotate 1 time. If you have the wrong drive another way to tell would have been to try props with different pitches, while this may not yeild the best solution it is an easier way to determine if the performance will improve before changing drives. I would assume your mechanic would be able to provide some used lender props for this.

To see what ratio you have but a half inch drive on the crank pulley bolt and turn the engine clockwise 2 revolutions and have someone watch the prop to see if it make 1 revolution if so it's 2:1 if theprop makes more than 1 revolution that 1.8:1.

Good luck and keep us posted.
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Old 07-21-2013, 05:58 PM   #18
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Thanks Mike!!! heading out to check today.. I have the new drive upper and lower complete for $750 with a 19p prop on it .. this prop is rated for the 1.81 gear ratio according to the maxum site that CountryME recommended.. this drive unit is a mercury marine reconditioned complete drive that came off a 28ft Rinker same engine I am told. The story behind this drive is that the father of the kid who sold me it bought it reconditioned before he got sick and eventually passed away.. the boat never got done so he is parting it out. Today I should have some news..
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Old 07-21-2013, 06:20 PM   #19
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JR, make sure you are getting what you need. http://bluewatermarinesvc.com/html/mercruiser_fyi.html lists info on how to tell that gear ratio the drive leg has inside it.
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Old 07-21-2013, 11:34 PM   #20
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Jr, thisboat is no pocket rocket but if you are looking for a nice cruiser that will run low to mid 30's this boat should do the trick. What Country provided will definitely help. Only caution is ifthe unit is rebuilt there is no guarantee that the same gears ratio was used, hence my recommendation to check as I outlined in my last post.


BTY: It may help to make a chaulk mark on the crank puller at 12 o'clock and across th prop hub to outdrive housing as reference points.
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