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4.3 efi Reverse Not Disengaging

E

eurocrap

New member
I have a 4.3 efi. year 2000

Big problems with reverse hardly ever disengaging after selecting neutral.
I have to select forward to overcome this and the shift/throttle can be stiff, but not always.

I can also overcome the problem by switching the ingnition off and starting again.
The shift/throttle is never stiff when the engine is not running.

On the rare occasions reverse does disengage it is usually accompanied by the engine running erratically.....speeding up then slowing to tickover.

The microswitch activation arm on the starboard topside of the engine appears to be erratic.......rarely moving up or down when the engine is running and moving up and down when the engine is off.....................help/suggestions needed please :mad:
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This is the nature of the "Dog Clutch" gear engagement.
Your Shift Assist is to aid in coming from gear, back into neutral. It is NOT needed when going into gear.

Sounds like your system is not adjusted correctly.... or you have a lower cable in need of replacement!
(your cable is ten years old now!)


Here is a suggestion:
With Engine OFF, and the drive in Neutral......, have a helper spin your propeller right/left rapidly and repeatedly.
While he/she is doing this, slowly move your shift selector from neutral to FWD....... then back to neutral while listening for the "ratcheting" sound!
At this point, go no further.... no need for full engagement!

Now slowly more towards a REV shift.
As the Dog Clutch teeth just begin to engage, you will hear the "ratcheting" sound.

See if the same amount of shift cable travel is required before you hear the Dog Teeth ratcheting sound in either direction from Neutral. (from Neutral being a key point here)

Point being: The "center position" from when you just begin to hear the Ratcheting Sound, is the center for the Dog Clutch "sliding sleeve".
(It's just the physics of this mechanical aparatus)
This is important, as this sliding sleeve is what we want to "Center" via making cable and/or linkage adjustments.

While this may sound "Crude" (and you will NOT find this in the OEM manual), it will give you an indication as to whether or not an adjustment is necessary.

NOTE: this will not work well with, and/or correct, a worn lower shift cable issue.
Nor will it help with an out of adjustment S/A micro switch.
It should give you a place to start!
 
Wow, comprehensive or what.! Thanks Rick 'Top Man'
I'm in England and the boat is in Greece so I will try your suggestion when I return in November.
I did have the 'lower cable' replaced in August this year because of this problem but possibly the 'Greek' adjustment was not done correctly!.
I don't understand why the Shift Assist Actuator does not appear to trigger the Shift Assist Microswitch, as my problem is coming from reverse gear
back into neutral. I have no problem coming from forward back in to neutral.
I also do not have a problem in selecting either forward or reverse from neutral. Any thoughts on this please Rick?
Thanks for your advice, Roger...aka Eurocrap
 
it only activates coming out of gear not going into gear. It has to do with the way the gears are back cut.

Could be corrosion or salt build up. Is the screw holding the microswitch maybe to tight not letting it move easy ? Is the button maybe hanging up?

Maybe it's the throttle cable stiff, disconnect it at the shift converter and then cycle the control, it moving easy?

Heres a link how to oil the cable.

How to Lubricate, Throttle Shift Cable
 
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