89 Mercruiser stuck in forward gear.

[natsgrampy]

89 Mercruiser, 3.0 L. just had the stern drive replaced with a new one from SEI. This was done by a boat mechanic not me. It tested fine on the muffs 3 different times.

Today I took the boat into the water. It ran well and shifted from forward to neutral to reverse and back. I shifted into reverse several times while still at the dock to be assured all was fine. There weren't any issues for about 45 minutes.

We motored out for about 45 minutes into the sound and marked some fish so decided to try our luck. When I shifted to neutral to drift, the drive remained in forward gear. I tried to shift it several times and it even stayed in forward when I shifted into reverse. Pushing in the throttle button had no effect.

I took it out of the water and had someone shift it while I observed the linkage / shift interrupter. All this seemed to work as it was intended, except, it stayed in forward gear at all times. The shift cable was replaced 2 seasons ago and hasn't caused any issues.

Could there be an issue at the drive where the cable and the shift shaft meet? Would this be the most likely cause?

I am looking for the best place to start looking for a solution. The throttle woks and the cables seem to be working from what I can see. The shift interrupter was working properly

Hope someone can help me out so I have her in the water for the 4th!!!!!

Thanks.

 

[stonyloam]

Try this: on the trailer, raise the outdrive up and look underneath to make sure the top of the intermediate shift shaft is properly mated with the bottom of the upper shift shaft. Have someone move the control to wot forward (engine not running of course) the intermediate / upper ss coupler should face directly foreward. Have them move the control to neutral and reverse, the shaft should rotate counterclockwise. If it does not, I suspect a problem with the cable or shift slide. SE 106 right?

 

[natsgrampy]

I will check that today thanks

 

[natsgrampy]

Yes it is the SE106.

OK so I had someone shift it all the way forward and it appears to face front. When it is shifted to neutral and reverse it rotates, but seems as though clockwise, looking up from underneath. When put into neutral it moves about 1/8 of a turn. When put into reverse, it continues in the same direction for another 1/8 of a turn.

I did all this without the motor running (of course). Yesterday I moved the shifter with the engine running, so, the drive was engaged in forward the entire time.

Here is what I found today. When it was shifted to reverse, all the way back, it would shift into reverse. When it was returned to neutral, from reverse, it would go into neutral.
When it was shifted from neutral to forward it would go into forward.
When shifted from forward to neutral, it would not go into neutral, it would stay in forward.
If I were to bring the throttle back to the center, and then, just a hair further back towards reverse, it will disengage from forward gear.

Could this be an adjustment of the shift cable?

I have done this for the original drive when I replaced the shift cable a couple of years ago. There were excellent instructions here that helped me tremendously. Would the procedure be the same with the SE 106, or, are there some variations?

Thanks again for all your help!

 

[stonyloam]

Sounds like a little adjustment is In order. The SE 106 is exactly the same as the alpha I.

 

[stonyloam]

Oh yeah you look at it from the top, so yeah you are rotating CCW.

 

[ktbarrentine]

When shifted from forward to neutral, it would not go into neutral, it would stay in forward.
If I were to bring the throttle back to the center, and then, just a hair further back towards reverse, it will disengage from forward gear.

Could this be an adjustment of the shift cable?

Hmmmm.... bringing the throttle back to the center IS neutral. Having to go just a bit further does soundd like a cable adjustment issue. If the adjustment affects going into forward, then it sounds like new lower shift cable time.

 

[natsgrampy]

Hmmmm.... bringing the throttle back to the center IS neutral. Having to go just a bit further does soundd like a cable adjustment issue. If the adjustment affects going into forward, then it sounds like new lower shift cable time.

Hope it's just an adjustment as the cable is only 2 years old.

Should I just disconnect and follow the instructions from there?

 

[havoc_squad]

This sounds like an upper shift cable adjustment issue. If the lower shift cable was set to Mercruiser specs in the service manual for the Alpha One Gen 1 drive, the most likely culprit is a poorly adjusted upper shift cable.

Edit:

It depends on how your upper shift cable works for going into forward. Whatever direction the upper shift cable goes into gear for, it would be adjusted too much in that direction.

I recommend you hunt down one of the free mercruiser service manual resources listed here at iboats to follow the procedure for adjusting this for Alpha One Gen 1 drives.

With the engine off and recommended that you disconnect your battery, follow the service manual procedure for how much you should adjust it to fix your shift cable issue.

A suggestion, every time you change gears or go to neutral, go to the prop and make sure it is 100% in the selected shift position. Also, make SMALL upper cable adjustments and check it before adjusting more. 1/16 of an inch adjustment increments would be a good rule of thumb.

 

[natsgrampy]

Adjusted the cable per the manual and viola it works!!!!