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1988 3.0 mercruiser gear drive problems!

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robbyrobs

New member
Hey guys obviously I'm new here and somewhat new to boats. Me and my dad have been working on a 1988 citation w/ the 3.0 mercruiser. we had the carb rebuilt and it runs great, so we get it in the water for a test run, and right away we have problems with the controls. its went into forward fine, but when you go to put in neutral or reverse, it's dang near impossible to get the controll to move back. If you pull back on it hard enough it will jump into reverse, but you really have to pull back hard on it. And getting it into neutral is impossible b/c your pulling so hard that it jumps into reverse. With the engine off the controll moves w/o friction, just when it's running is the problem. We ran the boat on the water full throttle with no problem and once we got it in reverse it went fine but just going from gear to gear. PLEASE HELP US!!! I hopt it's nothing major b/c we spent some good money redoing the whole interior :eek:
 
Re: 3.0 mercruiser gear drive problems!

Here is the text from the pic I attached before.......

The shift cutout switch, which is a normally open switch, closes momentarily when shifting out of gear due to resistance on the short shift cable going to the outdrive.

The centrifugal forces on the gears in the lower unit are what make it difficult to pull the throttle/shift handle out of gear back into neutral.

When resistance is increased the V notched plastic piece shown in the pic moves and activates the switch for a split second. When this occurs the ignition is momentarily grounded (shut off) and allows the clutch dog to disengage from forward or reverse gear in the lower unit.

To test: Start engine, depress the switch, if the engine dies the switch is good, if it does not die the switch is bad.

If it is good but does not work you may need to bend the switch arm a small bit to make the V notch activate it.
 
Re: 3.0 mercruiser gear drive problems!

Nice boat i have a 86' Citation. Try what Kghost posted. If it doesn't work, it should then you may have lower shift cable problems. Did you bye chance have the drive off?
 
Re: 3.0 mercruiser gear drive problems!

yes shift interrupt switch likely, run engine and close the switch manually, if the engine cuts out then the switch is working, then suggest replacing the shift cable from the engine to the outdrive as to much drag will cause the switch not to opperate fully causing your problem
 
Re: 3.0 mercruiser gear drive problems!

Volvopentatech,

The cable does NOT cause the switch NOT to operate, just so you know,

On a merc a bad cable will cause the switch to activate when it is NOT suspose to.

If to much resistance is in the cable it will cause the V notch plastic piece to move and activate the switch, most times when shifting into reverse..................
 
Re: 3.0 mercruiser gear drive problems!

thanks guys for all the advise. Haven't had a chance to look back at the boat yet, it's at my grandma's shop. I will check out the switch and do that test to see if it is working and make adjustments from there. Hopefully it's simple. Where can I buy a new switch and or cable if I need to?? I looked online a few places and saw cable packages that were 80$ different in price. couldn't find much on the switch.
 
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