Switch To Distributor

Hi,

I am working on putting a 4.3L Mercruiser setup together. The engine is a 1990 (pre-balance shaft / non-vortek) arrangement. There is a terminal block on the shift mechanism that ties into the white/green wire and the black ground wire. The white/green wire of course goes to the distributor.

My question, is how is this supposed to work? What is the operating principle behind it. I am very very familiar with Diesel engines and diesel engine controls for them (I design them), but for the life of me I cannot figure this arrangment out. Why would you want to ground it out when you shift from neutral to forward or reverse? I purchased the boat without an engine, so I never did see how everything was hooked up. Perhaps I am missing something.

Re: Switch To Distributor

It's the shift interrupt system used on Alpha I type outdrives. Read this how to on the operation of the shift interrupt system.

http://forums.iboats.com/showthread.php?p=1930449#post1930449

Re: Switch To Distributor

I believe what you are refering to is the shift interupter switch. It is designed to kill the engine for a microsecond while you shift to allow for smoother shifting and less stress on the shifting components and on the outdrive gears.

If it is not adjusted properly it can cause issues. If set up and working properly it does a great job and you wont even notice the "hickup" in the engine as you shift.

Hope this helps!!!

Re: Switch To Distributor

Well that certainly makes a lot of sense. Thanks for the information!!