Mercruiser Alpha 1 shifting problem

[Douglas C. McCrory]

When in driveway shifts fine. When in water shifts to drive and throttles, but will not go to neutral. It sticks and then with force goes directly to reverse. Any ideas would be greatly appreciated.

 

[tystick]

Re: Mercruiser Alpha 1 shifting problem

sounds like a lower shift cable is starting to go. Not sure why it would shift fine on muffs but the syptoms indicate cable. If cable - it is not worth trying to lubricate or fix - just replacement.

 

[Don S]

Re: Mercruiser Alpha 1 shifting problem

I would look at the shift interrupt switch or the wiring to it. It's not working. When in the water, the switch is used to cause the engine to die for a split second so the gears in the drive would release. Something that is not necessary on the muffs (No load on the prop )
If your cable was sticking, it would cause the engine to die completely, but you aren't getting any engine slowdown to help it come out of gear.

 

[Douglas C. McCrory]

Re: Mercruiser Alpha 1 shifting problem

Thanks Don , That must be what it is because there is a loose connection into the shift interrupter switch.

 

[shekinah5678]

Re: Mercruiser Alpha 1 shifting problem

Hey Don

I was having a similar problem on my 4.3LX Mercruiser with Alpha 1 Drive. I had just resigned myself to returning to the boat shop because getting to nuetral in the water was a pain in the but. I usually can get it in neutral but it takes shifting the control to the position and then kind of wiggeling it. Out of water it was fine. I just went out and checked the shift interupt switch. Sure enough it wasn't working. I replaced the engine last year and I must have wired it wrong then. After about an hour of tinkering I was able to reconnect it. Tested it on the muffs and works fine now. I haven't tried it in water yet but I'll bet the problem is solved. Thanks for the good advice!

Brad

 

[m1garand]

Re: Mercruiser Alpha 1 shifting problem

I am having the same problem with my 1978 Checkmate powered by a Mercrusier 140. I have looked for this shift interrupt switch but have not been unable to find it. I did find the neutral switch in the shifter, the tilt limiter while in reverse, and one other that is connected to the shift cable that seems to activate when at full throttle. Where do I look next?
Thanks
Dale

 

[Bondo]

Re: Mercruiser Alpha 1 shifting problem

and one other that is connected to the shift cable

Ayuh,....

That's the 1,....

And,.. It shouldn't activate at full throttle,... Ever....

 

[m1garand]

Re: Mercruiser Alpha 1 shifting problem

Thanks, Bond-o

 

[Wellcraft170]

Re: Mercruiser Alpha 1 shifting problem

I have a 1986 wellcraft 190 american with a merc 170. I've noticed that in the beginning of the day shifting is fine. But later on in the day when the boat is in foward gear, and you try to put it in neutral it stays in foward, and you have to play with it to get it into neutral. and its confusing because i just has the bellows and shift cable replaced last season. any suggestions??