Shift Interrupter Switch

[tdsr1]

I have a 1990 Mercruiser 3.0L with the DDIS ignition. I am replacing the DDIS with the EST type and have found that the shift interrupter switch on the DDIS and conventional ignition systems are the same providing a ground when shifting, but the the one on the EST system provide a positive "feed" , except when shifting. I am being lead to believe that I can bypass this and just not worry about it. Hey, if Mercury wanted it there...you know. Any opinions?

 

[freelunch]

Re: Shift Interrupter Switch

Of course it is always good to have all of your factory wiring intact. With that being said, I have my switch bypassed with no problems.

 

[tommays]

Re: Shift Interrupter Switch

You will have a HARD time getting the drive OUT of gear without a working switch which could lead to a bit of dock bashing


Tommays

 

[tdsr1]

Re: Shift Interrupter Switch

You will have a HARD time getting the drive OUT of gear without a working switch which could lead to a bit of dock bashing


Tommays

Ouch.....Hold On!!!!

 

[tdsr1]

Re: Shift Interrupter Switch

I rewired it with a positive feed, instead of the ground it originally provided. Now when the switch is activated, it sends current to the dist (EST ignition) and that momentarily shuts down the engine. Seems to work great.

 

[Don S]

Re: Shift Interrupter Switch

Did you put the distributor into base timing mode to set the timing? If so, what did you set the timing at?

 

[country_bumpkin]

Re: Shift Interrupter Switch

I have a 1990 Mercruiser 3.0L with the DDIS ignition. I am replacing the DDIS with the EST type and have found that the shift interrupter switch on the DDIS and conventional ignition systems are the same providing a ground when shifting, but the the one on the EST system provide a positive "feed" , except when shifting. I am being lead to believe that I can bypass this and just not worry about it. Hey, if Mercury wanted it there...you know. Any opinions?

What did you do with the old switch?

Wanna sell it?

Send me a PM if you do.

 

[tdsr1]

Re: Shift Interrupter Switch

Don,

Yes. The setup came with a connection to the dist with the "loop" to set the timing. It said to time it at 1deg. ATDC. It didn't seem right, but it runs great.

 

[tdsr1]

Re: Shift Interrupter Switch

What did you do with the old switch?

Wanna sell it?

Send me a PM if you do.

I am using the old one. I just removed the ground connection and connected it to the purple wire to provide a positive feed when the switch is activated.