350MAG MPI shift interrupter switchs

[ChipR]

I have a 2004 crownline w/ 350 mag mpi mercruiser engine with Alpha one outdrive. On the shift interrupter is there 2 of the switches or 2? One being a 2 prong hook up and the other being a 3 wire hookup

 

[ChipR]

And if it’s bad shouldn’t it kill the motor as soon as it’s unplugged? The 3 wire plug kills motor instantly but the 2 wire plug does Not. Motor will still run

 

[alldodge]

I'm scratching my head on your comments, there not making since for me.
What is your engine serial number?
Post a pic of the switch your talking about

 

[ChipR]

Engine serial # OM667448. It won’t let me post a picture. Says it exceeds the limit. Any other way I could send a picture

 

[muc]

You have two switches. Shift interrupt and gear indicator.

Also ---- you have open recalls on this engine ---- need to contact a MerCruiser dealer ASAP

This serial number is affected by Service Bulletin MC-2003-009,MC-2006-002. This service bulletin needs to be addressed. Please complete the required service work regarding this issue.

 

[ChipR]

Is the shift interrupter that’s the 2 wire I suppose? Is it suppose to kill the emotions when unplugged?

 

[ChipR]

Also how did you find out o had 2 recalls? I can find anything on them

 

[muc]

2 wire is gear indicator. Unplugged tells ECM that your in gear. Shouldn't kill the engine.

Recalls are on the dealer website.

Manual #36 ECM 555 Diagnostics part number 90-864573 will answer all your questions if you look at it.

.

 

[QBhoy]

One of them will shut down 4 cylinders if actuated. This is the shift interruption switch. Are you having issues with it ?

 

[ChipR]

Yes I am. When I come off plan to a slow troll in no wake zone and then shift to neutral the boat will surge and will not recover, so I proceed to put it in neutral to rev it and it’ll still be in gear and will die, I then start the boat again and it’ll be in neutral with a high idle. It runs perfect on plane and as soon as you put it in the water

 

[ChipR]

The bracket that the shift interrupter switch is on does not a activite the switch come from forward to neutral, I have the bot not running moving the shifter and the bracket never engages the switch... I’m confused on how it works

 

[alldodge]

The only time the switch is used is when the boat is IN gear and in the water. There has to be load on the prop for the switch to work when going into neutral. It will not activate when on the trailer

 

[muc]

Here is something written by a very knowledgeable man and it does a good job of explaining how the system works.

https://forums.iboats.com/forum/engi...t-system-works

it sounds like you may have two problems going on. The first one you should check is the shift cable adjustment.