Possible someone put wrong geared bravo 3 on?

Carsnmorellc

Ok so quick run down. Now the boat gets on plane, both new engines sound super strong and smooth. Issue is the port engine will not get past 4000 RPM.  The throttle can be all the way open and nothing. The starboard motor accelerates right past with ease.  With everything I've done to the boat now, motors, props, I honestly think who ever replaced the port drive put a bravo 3 with the wrong gears in it.  My boat should be 2.20 I believe. Could the symptom I'm seeing be gear related?

aero3113

Is it possible your throttle cable needs to be adjusted?

Liberty44140

Is it possible your tach is wrong? Tap it with your phone?

Carsnmorellc

I surely hope not as I just paid for that to be done when the engines were put in, but I guess that's something I'll have to double check.  This marina was under different management at that point and not really reliable. 

Carsnmorellc

@Liberty44140 yes I know the issues with the tachs. I hit them all the time, but I can also hear the port engine not at the same RPM level as Starboard.  It definitely stops at 4k and doesn't get there as quick as the starboard.

trip_n

just asking=same size props and tuning= and condition=no damage
how did it run b4 the prop change
with or with out trim=any difference 

Carsnmorellc

The boat would never get above 3200 before. Now with new props my wot on starboard is 5100 and 4000 on port. No damage. Played with all different trim levels. 

dalek

If you can see the prop, you could put the engine in gear, turn it off, and turn the crank nut with a wrench. Count the ratio.
Alternatively,you could try travelling at a certain RPM (2000 maybe) using each engine in turn. A lower ratio should give more boat speed per engine revolution.

Stodge

I had to have my uppers rebuilt.  The wrong gear set went into one of them.  It wasn't a big difference in ratio but enough to see a difference.  That was corrected over the winter and I'm seeing more even performance.

Carsnmorellc

What were your symptoms @Stodge??

john744

BINGO !!!!  Of course I'm not able to say that's what you've got, but it happened to me. I have a 2002 310 FV. When I bought it a few years ago, we took her out for test run and had that exact problem. At first they thought it was the fuel regulator.... changed it but problem persisted.  Then they thought it might be mis-matched props. Swapped the props from port to starboard. Problem persisted.  The shift cable needed to be adjusted in the port drive so while he had it off decided to swap the drives. BINGO !!!  problem went from port side to starboard.  So a little digging in the Mercruiser database uncovered a previous repair where the gears were replaced.  And, yes, they put the wrong gear ratio in.

A long shot. You bet.  But it happened to me..............  Good Luck.

Stodge

Carsnmorellc said:

What were your symptoms @Stodge??

Port would not pass starboard in RPM.  It would keep up, but not pass.  And I had to have the throttle more advanced on port than starboard.

Carsnmorellc

@Stodge You are explaining exactly whats happening.

Carsnmorellc

Now, should I have the gears replaced or go ahead and just buy a remanufactured drive with correct gears in place??

trip_n

maybe just have it checked=to confirm

Carsnmorellc

@trip_n absolutely, but how in depth is changing gears compared to buying a reman outdrive?  

Stodge

I'd expect it to cost less to have a new gear set installed.  But agreed that the ratio needs to be confirmed before any action.

Black_Diamond

It is a whole disassembly to replace gears. I would for sure verify the ratios before plunging into that. 

Carsnmorellc

@Black_Diamond I will be sure to make marina spin the props first to find out, but it seems if they are the wrong gears it would be best to just replace drive.  

trip_n

you say new 6.2 horizons =new or reman=whats the recommend rpm range=did you buy and have installed 
also every body buying hill props=would they need to know the gear ratio to properly tune ?
also thepriceisright = was having rpm issues=haven't heard back from him

Carsnmorellc

Reman.  I'm supposed to be at 5100-5200 WOT.  With the new 20P the starboard motor is at 5100.  Port has gotten above 4000 a few times but I have to hold starboard around 4500 for a long time for it to catch up.  I bought and had motors done, person before didn't take care and also didn't have a very good attention to detail.  I've worked out a lot of issues so far.  The original marina was absolutely worthless, my marina was crap until about 3 months ago, they hired a new manager and new mechanic.  Have seen a world of difference.  

Carsnmorellc

But the port outdrive was replaced by previous owner, they went cheap of course..... its an older style drive with out the adjustment washer you can turn backwards to get the drive closer to the stern.  And I am pretty convinced its the wrong gears as well.

Stodge

@Carsnmorellc you might want to try and locate the serial numbers from the drives and see if you can find anything out about them.  But if they are reman, then it will not likely tell you much.  With luck your new mechanic can figure it out without too much trauma to either you or the boat.

Black_Diamond

Without that washer part to allow the drive to tuck in more, it will never be “right”.