Shift interupter question

2kvert

Seaman
Joined
Mar 15, 2014
Messages
64
I've had the lower unit and engine out of my 4.3 Mercruiser Alpha One several times in the last few weeks I'm having trouble with it stalling on the mouse when I go into reverse reading the sticky post it says I probably have something binding in the lower unit can anyone tell me what I need to look for in this. is something I can adjust it am I going to need to replace something?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,425
go to the stickies and read on adjusting the lower shift cable.
 

ajent

Cadet
Joined
Jul 25, 2011
Messages
9
Remove the shift cable from the throttle plate. Have someone spin prop, counter clockwise, and pull the cable end. This is the reverse shift, it should slide into gear smoothly, no binding. If it is sticky, you need to take drive back off and find out why.
If it works normal, adjust the reverse shift microswich or cables as needed
 

2kvert

Seaman
Joined
Mar 15, 2014
Messages
64
Remove the shift cable from the throttle plate. Have someone spin prop, counter clockwise, and pull the cable end. This is the reverse shift, it should slide into gear smoothly, no binding. If it is sticky, you need to take drive back off and find out why.
If it works normal, adjust the reverse shift microswich or cables as needed

I’ll look at that, but I’m not familiar with the reverse microswitch I only have the interrupter to my knowledge
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,133
Ayuh,..... In the mercruiser section,.....

I think achris might even have a video on it in there,....
 

tank1949

Lieutenant Commander
Joined
Apr 4, 2013
Messages
1,911
I've had the lower unit and engine out of my 4.3 Mercruiser Alpha One several times in the last few weeks I'm having trouble with it stalling on the mouse when I go into reverse reading the sticky post it says I probably have something binding in the lower unit can anyone tell me what I need to look for in this. is something I can adjust it am I going to need to replace something?

Those interrupt linkage wear out. Did it work correctly before pulling motor/drive? My gut tells me that you may have inadvertently spun the barrels too many times or bolted the interrupt so it is in a bind. If the interrupt switch freely bounces up and down while going into fwd or rev, then look elsewhere. My guess that it bounces and stays up or down (full interrupt mode). If my memory serves me correctly, complete fwd and complete rev only have a 45 degree ark on the OD. You will need a buddy operating helm shifter controls to make sure neutral, fwd and reverse (in prop). If OK then go back to interrupt.
 
Top