Drive stuck in forward position

s_explore

Seaman
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Oct 15, 2021
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54
Hello,

I just bought a boat and the drive wasn't install on it. So I did install it but now the shifter is stuck in the forward position. I can't shift it to neutral or reverse. Is this can be a problem of installation or the shifter cable are not adjusted correctly?

Thank you, Sam
 

Bt Doctur

Supreme Mariner
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Aug 29, 2004
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19,292
Did you check the cable operation before mounting the drive?
Did you check the drive shifting before you mounted it?
Without telling us WHAT you bought and WHAT drive and WHAT serial number its impossible to answer you correctly
 

s_explore

Seaman
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Oct 15, 2021
Messages
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I did check the shifting operation and it was working good. I was able to start the engine without the drive since I was able to put it in neutral position. But with the drive I can't go in neutral.

The drive is a mercruiser pre-alpha I beleived MC1 is what they called it. The engine is a 1998 mercruiser V8 5.7L.

Honestly I don't know a lot about those engine and drive, I am pretty new to this kind of stuff. I think I installed the drive correctly, put the boat in forward position, align the shifter cable to fit in the drive. I think I am doing to remove the drive again, but I am not sure what should I check to see if the shifter cable work as supposed.
 

Bt Doctur

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Someone may have installed the shift shoe incorrectly. Remove the drive and check to see. Looking down from the top of the drive the brass shoe is straight for Fwd. Turned slightly to the left CCW, is neutral, turned all the way to the left CCW is Rev.
 

s_explore

Seaman
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Oct 15, 2021
Messages
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Someone may have installed the shift shoe incorrectly. Remove the drive and check to see. Looking down from the top of the drive the brass shoe is straight for Fwd. Turned slightly to the left CCW, is neutral, turned all the way to the left CCW is Rev.
Ok yeah I will check that. If the shoe you are talking about is what I think it is, I did put it in straight position but maybe it did move when I installed it. I think there is one shoe on the drive also and I did put it straight too.
 

Bt Doctur

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You need to do the test in my post. If the shoe moves to the right CW ,that needs to be fixed first.
To install :
control box full fwd
drive in fwd ,shoe straight ,prop locked CCW
use wood to adjust the height to slide in shaft and while slightly turning the prop CCW to turn the inputshaft slightly to align the splines and the drive will literally fall on to withing a 1/8th inch if the engine alignment is correct.
 

s_explore

Seaman
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You need to do the test in my post. If the shoe moves to the right CW ,that needs to be fixed first.
Ok so the shoe is not supposed to turn CCW? If it's moving it's a problem? Be cause I remember being able to move the shoe with my finger.
 

s_explore

Seaman
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Messages
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see post 5 yes or no
Hum yeah I was able to move it that way. I've put it in forward position before putting it back to the boat. So I did everything fine? I will remove the drive and reinstall it one more time to see.
 

s_explore

Seaman
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Messages
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Ok so I removed the drive and made some inspection and took pictures.20220719_201508.jpgThis doesn't want to be straight. It only want to go in neutral or reverse position. Am I right thinking that? Because the shifter move as supposed without the drive. I took video of the drive if you can confirm what I think please. On the other video the shifter seems that it was stuck when installed in the drive. So that might also be a reason why the boat was stuck in forward position.
 

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nola mike

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You're off a tooth; that shifter should be straight ahead in forward. Was the drive split for servicing? If not, and you don't know the maintenance history of the boat, it's time to replace the impeller anyway. Also, on the second video it doesn't look like the roller on the shift shaft is engaged correctly in the fingers of the shift slide, although I can't tell for sure from that video
 

Bt Doctur

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Easiest way it to build a stand from 2 x 4 to set the drive on. Will post a pic tomorrow. Remove the trim tab and underneath is another bolt or allen ,remove it. remove the 2 bottom nuts using a 5/8ths deep socket.

Remove the front nut, then using a 5/8th open end loosen the 2 side nuts as far as you can. The drive should start to separate. If not wedge a large flat screwdriver between the top of the nut and the housing and pry up.
If it still wont budge, tighten the nuts down a bit and insert a 7/16ths open end wrench as a spacer and unscrew the 2 nuts prying the upper unit up
 
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When the two halves of the drive are split and being put back together, they must both be in forward the whole time, to do that, you have to keep pressure on the prop CCW while rotating the splined shift shaft CW on the lower half until it locks in gear. Pressure on the prop CCW the whole time the halves are mated back up. Some people use a bungee cord on the prop, I just hold it with my hand. The shift shaft in the upper half of the drive should be facing forward while the lower is locked in forward gear as they are mated. It sounds like yours may have bumped out of gear in the process of mating the halves. Keep an eye on the stainless steel washer on the splined shift shaft on the lower half of the drive, if it falls off/out in the process you will have problems, also keep in mind the Quad O-ring on the starboard side of the drive, it seals the oil passage between the two halves.
 

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s_explore

Seaman
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All right so as what I understand, my drive doesn't want to shift in forward position.

From what the last owner told me, the drive was remove during the winter for storage. He didn't told me much actually, so it is possible that it wasn't working when I sold it to me...

@nola mike Yeah on the second video the shaft disengage from the roller. It was like this when I removed the drive so it might have move when I installed it.

@Bt Doctur The procedure you wrote is to dismantle the drive right?

@Eric 3.7LX Alpha 1 Thanks for the info. Since I think my drive won't go in forward position, I wasn't able to put pressure on the prop CCW since it didn't want to lock in position. I guess I need to open the drive and see what is going on.

Does anyone know if the impeller on the pre alpha are the same from the alpha? I'm looking for the part number
 

Bt Doctur

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All alpha series use the same one, the Alpha GEN II use a different one.
What is different is the water pump base. There is MC1 ,R and MR.
You drive does shift into fwd but just not in the right spot. The brass shoe MUST point straight forward when the prop is locked CCW
 

s_explore

Seaman
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Messages
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All alpha series use the same one, the Alpha GEN II use a different one.
What is different is the water pump base. There is MC1 ,R and MR.
You drive does shift into fwd but just not in the right spot. The brass shoe MUST point straight forward when the prop is locked CCW
Ok so I guess I need to adjust it? And for that I will need to open the drive if I did understand correctly. One thing that is weird is the drive won't locked CCW, I can spin the prop CCW with no problem and it won't lock. I don't know if this is a problem.

I think I have an MC1 drive, but it's hard to tell. It seems there is no part number or nothing on the drive.

I'm gonna say it again, thanks a lot for the help I really appreciated it.
 

Bt Doctur

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If the prop shaft does not lock CCW with the shoe turned fully CW you have a additional issue. No matter how the shoe is on the splined shaft it can shift into fwd with the prop locked CCW. but to install the drive the shoe must be in a straight line
 
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