Shift interrupt switch issues

[Berniemcc]

I’ve replaced the lower shift cable and adjusted as shown in mercruiser service manual. Problem I’m having is when moving to reverse the interrupt switch kills the engine. I’ve tried multiple times to adjust the cables using both mercruiser and YouTube video information with the same results. Going into reverse the interrupt switch shuts off the engine.
anyone have this experience and suggestions how to correct it. Thanks

 

[Bt Doctur]

Did you screw the brass nut in all the way

 

[achris]

Shift interrupt activation in reverse (given all the shift plate adjustments are correct) is usually built up crud in the bell housing, bottoming out the slide.

Chris........
(Yes, you made a comment in the video.)

 

[Berniemcc]

Thanks for the responses but now I’ve got a question about what you’re asking about “screwing the brass nut All the way in”. If you’re asking about the threaded rod that is locked by the brass jam nut- yes it’s all the way in
as far as the junk build up in the bellhousing - when I reinstalled the shift cable I made sure everything was cleaned out but I am beginning to wonder if the cable I bought - I believe made in China- is made to the correct specifications
Any additional comments are welcomed
thanks in advance

 

[Bt Doctur]

you siad you installed a cable, where it threads into the housing at the stern you cannot have more than 2 thread exposed. If you bought a complete kit there is no crud in the shift slide.
What did you install and what came with it?

 

[Bt Doctur]

 

[72 Chesapeake]

Reverse seems to be the common problem with the interrupter switch especially when out of adjustment. I installed a new cable last year, adjusted the brass barrel on the transom close to where it was previous. Running in yard it would shift both gears fine but in the water would grind in reverse because i didn't have full engagement with tension on prop. On the reverse lock valve there is a slotted adjustment where the travel can be adjusted longer or shorter up or down the slot. I went up slightly at the dock and shifting seems good. Also i have used this in the past to compensate for cable stretch or wear but hopefully with new cable i will be good for a while. Only adjust a slight amount at a time because this adjustment affects forward as well. Between this and the brass barrel you should be able to get it working as long as things are good in the lower unit. I have also dealt with the shift slide in the lower unit getting corroded after a while, so when its apart I grease it well.

 

[Berniemcc]

I bought a new cable that was Chinese made so now I'm wondering if the cable length is what's causing my problem. Does anyone know if the barrel that screws into the shift cable (and gets locked with the jamb nut) was lengthened or shortened would give the correct overall cable length. Of course I'm not sure what the total length should be - too long or too short - but I'm looking for ideas as it's hot here in Nashville and I wanna get on the water soon!