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Shifting problems

M

mgwyn

New member
2005 VIP 18.5 4.3 mercruiser. Occasionally doesn't want to come out of forward gear when shifting into neutral. The shifting lever is worn and a little loose.
 
First can you take a picture of your shict control so we can see what it is?

Second, what is your idle rpms?
 
You most likely have a Merc A drive... of which is a Dog Clutch drive.
When the propeller is trying to achieve forward propulsion (even at low RPM), the Dog Clutch teeth want to remain engaged.

Your engine is equipped with an SI...... (Shift Interrupt system)..... and is a requirement for any Dog Clutch drive.

While the operator is attempting to reach neutral..... the SI momentarily interrupts the ignition source, causing RPM to stumble.
During this RPM stumble, the Dog Clutch relaxes momentarily, allowing for disengagement.

All must be adjusted correctly and working correctly.
The adjustment must be made while the boat is in the water as to create prop thrust against the Dog Clutch.
(don't allow anyone to tell you differently)

All shifts from gear into neutral must be made quickly and decisively.


.
 
Last edited:
Will post pic of shifter today. After returning from lake adjusted idle rpm down to 800. Was 1000. At the lake advanced timing because it seemed retarded too much. Ran better afterwards.
 
Shift cable and shifter
 

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mgwyn said:
Will post pic of shifter today. After returning from lake adjusted idle rpm down to 800. Was 1000. At the lake advanced timing because it seemed retarded too much. Ran better afterwards.
Click to expand...

Ayuh,... Welcome Aboard,.... Ya really oughta set the timin' with a light,...

Idle at 650/ 750 rpms,...

Is the Shift Switch in yer picture, hooked up, 'n workin',..?? Test it,...
 
I found ground lug from switch not connected. Connected it still no change to engine when lever is pushed down. Checked other wire to denso engine module was good. What else could it be but Denso engine module
 
You mention Denso module, what part number? If this is a 4.3 replacement auto , may not be programmed for shift interupt
 
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