Port engine stalls going into gear

[ehe]

Why does port engine quit when it goes into gear? shift interupter switch seem ok, but linkage does not release button to keep engine running. Can the switch be jumped or disconnected? What is the purpose of the interupter switch? Can the shifter cable be out of adjustment or worn out, which causes the the switch to be press to long?
Boat is a 1998, 290 Weekender, twin 4.3, alpha drives, engine hours read under 200, but not sure. Just purchased last week for a steal.

 

[Maxiestaxi]

switch momentarily stalls engine so you can shift gears, yes it is necessary. If the shift cale is adjusted wrong it will cause problem. If you have a service manual it there is a section on adjusting the switch. I had a cable binding that caused the same problem. Had to replace lower cable to fix the problem

 

[Kameroo]

I had that issue on my 280 twin. It was a lower shift cable adjustment. The idle was also off a little, which didn't help. The interrupter helps the gears to mesh--maybe somebody will have a better description of how this works.

 

[techmitch]

the interrupter switch is mainly for shifting into neutral as this is when the drive has a load on it and will not come out of gear, a momentary interruption of the ignition. aids in this process. chances are that your lower cable is binding and causing your stall.

 

[jitts3]

This is the best way to describe the interuptor and its need. Drive a car or truck with a stick shift transmission. Go down the road and try to shift to neutral without the clutch while applying power. It will not come out. You will be able to do it once you have no power load in the gears. Now the same applys if you are using the engine to slow down the car. There is a load on the gears, it matters not from where.
When the boat is at idle and in gear the gears have a load on them. The interuptor shakes the engine to take most of the load off and allow it to smoothly disengage. This could be accomplished if a boat had a clutch. This is easier.
FYI I drive for a living a Peterbilt Truck. I do not use the clutch except to stop and take off. Once moving I do not need the clutch. If a match the engine rpm with the desired gear and there is no difference in the speed between the two gears I'm trying to enguage, she slides right in. Now if I am applying power or using the Jake (engine) brake to slow the truck, I willl not be able to get it out of gear, no matter how hard a rip on the shifter.
Hope that helps:thumbsup:

 

[techmitch]

quote: The interuptor shakes the engine to take most of the load off

i beg to differ: a momentary interruption of the ignition. aids in this process.

 

[geriksen]

Why does port engine quit when it goes into gear? shift interupter switch seem ok, but linkage does not release button to keep engine running. Can the switch be jumped or disconnected? What is the purpose of the interupter switch? Can the shifter cable be out of adjustment or worn out, which causes the the switch to be press to long?
Boat is a 1998, 290 Weekender, twin 4.3, alpha drives, engine hours read under 200, but not sure. Just purchased last week for a steal.

You need a new lower shift cable. Also have them replace the bellhousing shift shaft bushing and the seals. That is likely where the water came from that ruined the cable.
Very common problem.