Volvo 4.3 Neutral Switch Problem

AlanBurnett

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I have twin Volvo 4.3 IO's and the starboard engine stalls when I shift sometimes. I have noticed that if I shift into neutral and pause, then the engine doesn't stall. If I shift quickly, like when I am trying to get into my slip at the marina, the starboard engine stalls and it won't start in the neutral position. I have to disengage the control lever (push out of engagement into the cold start position), then the engine starts.
I am wondering if I have a faulty switch. If I shift slowly, the engine runs great all day long, it only seems to falter when I am docking and having to shift quickly to avoid hitting the side of the slip.
Any Ideas would be helpful.
 

Bondo

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the starboard engine stalls and it won't start in the neutral position.

Ayuh,.... Welcome Aboard,.... Won't start as in the starter won't engage,..??

Or won't start when crankin' it over,..??

The neutral safety switch is in the starter circuit, 'n has No bearin' on a runnin' motor, so it's Not causin' the motor to stall,...
 

alldodge

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the starboard engine stalls and it won't start in the neutral position. I have to disengage the control lever (push out of engagement into the cold start position), then the engine starts.

So after the motor stalls, you move the shifter into neutral and the motor will not crank. So you have to change to throttle only and by moving the shifter around it will then crack again? If this is correct then you either have a bad switch or it needs adjusting.

When its cold at the first start of the day do you have any issues getting it to crank?
Moving the shifter a little back n forth while holding the key in the start mode, will it start to crank?
 

AlanBurnett

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Sorry for the confusion.
The engine starts great and runs great all day. (5 hour cruse on SF Bay) Shifting from forward to reverse no problem so long as I pause in the neutral position before changing gears.
When I get to the dock/slip, if I shift quickly from forward to reverse the engine stalls. When I try to start it in the engaged neutral position, it cranks but won't start. If I move it out of the engaged neutral position, it starts right up.
 

Bondo

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When I get to the dock/slip, if I shift quickly from forward to reverse the engine stalls. When I try to start it in the engaged neutral position, it cranks but won't start. If I move it out of the engaged neutral position, it starts right up.

Ayuh,.... That's not a neutral safety switch issue,.... it only effects the Starter,....

That's the Ignition circuit wirin',.... keyswitch wirin' maybe,..??

The shifter, Shouldn't have anything to do with it,.....
 

AlanBurnett

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At no time does the engine fail to crank. I just had a lot of work done to both engines including carb rebuilds, valve jobs, and a few other minor things.
The engine fires right up when cold and runs strong all day.

The only time it stalls is when I am shifting fast from forward to reverse in order to avoid hitting the side of my slip when parking the boat. The boat is a Carver with an enclosed fly bridge and any little wind creates a challenge parking it. So, that's what causes the need to quickly reverse sometimes to readjust my entry angle into the slip. Of course, the starboard engine is the one with the power steering and that creates a whole new set of challenges when it stalls.
 

alldodge

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Boatinfo is out right now so cannot double check, but believe you should be idling at 650 RPM. Need to use a handheld tach to measure. I'm thinking your idle is a bit to low or your timing has not been set correctly.

Only thing that is puzzeling is the crank but not start unless you move the shifter after it stalls from going from rev to fwd. Your motor doesn't have an interrupter and its not the neutral safety because it will crank over
 

QBhoy

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Unless I'm missing something...could it not just be the idle speed ?
Do you have a cone clutch? Is it a DP?
 

AlanBurnett

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First of all, thank you all for your comments and suggestions. I know very little about mechanics and am at the mercy of those who work on my boat. ​
The diel speed out of gear is 750 to 800. When I put it in gear, it drops to about 650.
I know that timing can be an issue, but there doesn't seem to be any other symptoms. The engine runs great. I'll buy a hand held tach and have the timing checked.
 

AlanBurnett

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Anyone have any guess why the engine starts right up when I disengage the transmission by moving the handle out of position?
 

alldodge

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Anyone have any guess why the engine starts right up when I disengage the transmission by moving the handle out of position?

For my self no clue. If it would not crack then I can agree, otherwise no

The idle speed out of gear is 750 to 800

I see this as a tad high, maybe the carb needs adjusting, thinking should be a bit lower (700 to 750)
 
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