Upper shift control cable Mercruiser 228

Brock96

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Jul 16, 2012
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Hello - Boat 1979 Carver Monterey - Mercruiser 228 - 305
Part 1
When I shift into gear with the upper helm lever ( engine not running) the shift lever on the shift plate does not move so I assume the upper shift cable is broken. I cannot find a mechanic so l have to replace the cable myself - is this a simple procedure where by I just disconnect every thing and haul the cable out - do l mark the cable in anyway (where attached to the shift plate ) Cannot start engine as I believe it is stuck in gear. The original problem is that the engine stalls when put in reverse - suspect lower shift cable

Also there is a rubber tube ? attached to the Helm box - would anybody know what this is and it's function
Regards - appreciate your help
 

Brock96

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Joined
Jul 16, 2012
Messages
12
Hello - Boat 1979 Carver Monterey - Mercruiser 228 - 305
Part 1
When I shift into gear with the upper helm lever ( engine not running) the shift lever on the shift plate does not move so I assume the upper shift cable is broken. I cannot find a mechanic so l have to replace the cable myself - is this a simple procedure where by I just disconnect every thing and haul the cable out - do l mark the cable in anyway (where attached to the shift plate ) Cannot start engine as I believe it is stuck in gear. The original problem is that the engine stalls when put in reverse - suspect lower shift cable

Also there is a rubber tube ? attached to the Helm box - would anybody know what this is and it's function
Regards - appreciate your help
The rubber is kind of electrical wires ?
 

harringtondav

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Your starting problem could be the neutral switch in the controller, or the shift interrupt switch on the shift plate. If it starts and immediately dies it's likely the interrupt switch. The interrupt switch can be verified by disconnecting the leads which will allow a start, if the switch is faulty or misadjusted.
Replacing the cable isn't the worst job. You have to remove the controller to disconnect it. Depending how the boat is built, threading the old cable out and the new one in can require a fair amount of trim removal. Using a fish cord to pull the new cable could help.
Given the cranking issue, you might consider replacing the controller and cable. Disassemble the controller before ordering a cable so you can see if it has a problem with the neutral throttle linkage or the switch.
The upper cable's attachment to the plate won't affect shift timing. This is in the lower cable adjustment.
 

Brock96

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Your starting problem could be the neutral switch in the controller, or the shift interrupt switch on the shift plate. If it starts and immediately dies it's likely the interrupt switch. The interrupt switch can be verified by disconnecting the leads which will allow a start, if the switch is faulty or misadjusted.
Replacing the cable isn't the worst job. You have to remove the controller to disconnect it. Depending how the boat is built, threading the old cable out and the new one in can require a fair amount of trim removal. Using a fish cord to pull the new cable could help.
Given the cranking issue, you might consider replacing the controller and cable. Disassemble the controller before ordering a cable so you can see if it has a problem with the neutral throttle linkage or the switch.
The upper cable's attachment to the plate won't affect shift timing. This is in the lower cable adjustment.
Thankyou for reply
Part 2
I have movement again between the Helm control box?? (Holds the two cables shift and throttle cable) and the engine. Took the control box apart - took the shift cable off and pushed and pulled and the shift lever on the shift plate was moving.(moved easily)
Now in the housing each cable runs through a barrel. I assume for positioning. I cannot find the barrel for the Shift cable. The barrel has a hole through it so it cant fall off. I have to assume that it broke (probably when I was changing gears when testing the shifting)
Where do I get a new barrel ? - I will try every Marina around me. Thanks

Neutral switch - is that the device within the control box that only allows the engine to start in neutral.
Originally - the engine starts and runs great - the engine would stall going into reverse and not forward then along came the upper shift cable problem - Hopefully that adjustments will stop the Interrupter switch from stalling out the engine

Going to put it all back together and get a marine mechanic to make the necessary adjustments including the testing of the shift Interrupter switch - My fear is that the problem is the lower shift cable.

I f I understand correctly the shift Interrupter switch only comes into play when coming out of gear.
Thanks again for your reply
 

harringtondav

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Where do I get a new barrel ? - I will try every Marina around me. Thanks
I assume you have a Mercruiser control. They publish parts catalogues for most of these. ...availability on a 1979 controller is likely to be iffy. Ref my comment on purchasing a replacement.
Neutral switch - is that the device within the control box that only allows the engine to start in neutral.
Yes
My fear is that the problem is the lower shift cable.
The lower is normally the problem. You can test it similar to what you did with the upper. (I'm assuming your shift plate assembly is the same as in my 1996 Merc installation manual). Remove the upper cable from the lever and also the shift assist device if installed. You should be able to easily move the lever and lower cable both directions until the dog clutch locks the prop in both FWD and REV without causing the shift interrupt yoke to move and close the switch. Any resistance will trip the switch.
I f I understand correctly the shift Interrupter switch only comes into play when coming out of gear.
Yes, and only with the boat in the water where the prop load on the dog clutch will cause the yoke to move and close the switch.
But a bad cable per above will trip the switch. Missadjustments in the barrel position or cable position in the lever slot will also cause problems. When my previous Merc boat was new the engine would kill going into gear. The lower cable anchor stud moved out of position in the lever's slotted hole. Bottom of slot is specified.
Final note. All cable and shift assist lock nuts must not be fully tightened. There should be enough clearance so the washers spin freely.
 

Brock96

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Thks for replies
The upper control shift cable is bad - one of the barrels is broken and gone. been to a local Mercury dealer and ordered a new cable - It took me 5 minutes to remove the old cable
Will be back when it arrives (week)
 

Brock96

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Thks for replies
The upper control shift cable is bad - one of the barrels is broken and gone. been to a local Mercury dealer and ordered a new cable - It took me 5 minutes to remove the old cable
Will be back when it arrives (week)
While I am waiting I have a question
With the engine not running and I move the upper control lever in and out of gear is this happening in the outdrive
 

Brock96

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Not understanding your question. Is what happening in the outdrive?
This is one of those lack of knowledge question - in the lower unit are the gears moving in and out of forward and reverse when l use the upper control shift lever. = engine not running. -- I understand that it is not a good idea to shift gears with the engine not running
The last time with engine running it would not come of forward gear = I am asking myself is it still stuck in gear. - its a rookie question but l need to know the procedure to reinstall the new cable and the shift lever =
I think I have answered my own question =the gears are moving
Thanks for your help
 

harringtondav

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Assuming you have an Alpha drive, both FWD and REV gears are turning when the engine is running. Between them is a sliding dog clutch which couples either gear to the prop shaft depending on your choice of FWD or REV. Shifting into either gear with the engine off doesn't hurt a thing. The shift linkage is spring loaded. If the dog clutch doesn't engage..no problem.
Your bad upper shift cable likely caused "The last time with engine running it would not come of forward gear". When you get the new cable installed you'll probably be OK since the lower cable and adjustments were working prior.
IIRC (not in front of my manual now) the upper cable's adjustment at the shift plate is fairly simple. Set the cable's length at he shift lever so neutral = neutral. ...prop spins with no ratcheting in either direction. ...You may also have to time the throttle cable so it doesn't move the carb linkage before a gear is engaged.
 
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