Mercruiser Alpha 1 Shift Interrupt

[Evander]

I have a 2023 Chaparral with an Alpha 1 drive. Having issues with the engine stalling when I shift out of reverse into neutral. I've confirmed that the shift interrupter switch engages and releases normally when pressed and released by hand.

In checking operation with the boat in the water and tied up at the dock it appears the actuator lever (the part that rotates up and down to press the interrupter switch when shifting) seems to "hang up" and keeps the switch pressed for too long, then the engine stalls. It only happens coming out of revserse, I have no problems going from forward to neutral or from neutral to either gear. If I jiggle the shift lever at the helm a bit right after a I shift into neutral it seems to free up and not stall.

Is there a need to lubricate or adjust the lever?

 

[nola mike]

I have a 2023 Chaparral with an Alpha 1 drive. Having issues with the engine stalling when I shift out of reverse into neutral. I've confirmed that the shift interrupter switch engages and releases normally when pressed and released by hand.

In checking operation with the boat in the water and tied up at the dock it appears the actuator lever (the part that rotates up and down to press the interrupter switch when shifting) seems to "hang up" and keeps the switch pressed for too long, then the engine stalls. It only happens coming out of revserse, I have no problems going from forward to neutral or from neutral to either gear. If I jiggle the shift lever at the helm a bit right after a I shift into neutral it seems to free up and not stall.

Is there a need to lubricate or adjust the lever?

This is typically the symptoms of a worn lower shift cable, though you shouldn't have any issues on a 2023. First step is to disconnect the lower cable and try shifting it manually--there should be practically no resistance.

 

[Evander]

Thanks! Agreed, I would not expect any issues in just the 2nd year of operation but will try your recommendation this weekend. While I have it apart, is it worth hitting the cable with a shot of silicon spray for smoother operation?

 

[kenny nunez]

Another thing that may help. There is a “V” shaped stainless wire spring that centers the “V” notch interrupter lever. Remove the lever remove the bolt that holds the spring and try spreading the spring wider giving more tension.
When the cable is in good condition you should be able to manually move the inside end with just 2 fingers . If it takes a lot more than that you need to remove the drive and inspect the slider for build up. The cavity might just need to be cleaned and lubricated.

 

[nola mike]

Thanks! Agreed, I would not expect any issues in just the 2nd year of operation but will try your recommendation this weekend. While I have it apart, is it worth hitting the cable with a shot of silicon spray for smoother operation?

No, no lube on the cable. If it's binding it needs to be replaced