Shift Interrupter adjustment 1987 330hp

[DanT]

The Quicksilver shifter and linkage on my 1987, Alpha 1, 330HP, Mercruiser was not pushing the clutch dog far enough to engage the reverse gear. (It only made a clicking/grinding noise.) So I adjusted the cable on the interrupter, that went to the lower unit, so that it had more travel in each direction.

Now the clutch dog engages the forward and reverse gear just fine, but the interrupter kills the engine when I try reverse. I can probably adjust the linkage so that it doesn't do this, but then I ask myself....why would the interrupter do this while the engine is running? If adjusted "correctly," the position of the interrupter will close (ground the coil), with the commander pushed forward or backward...weather running or not. Right? What good is that?

I looked to see if there was a diode or relay that would sense if the engine was running and thus negate the interrupter, but none of my schematics show this.

At first, I thought any fool would know what the interrupter was for...to keep from starting the engine while it's in gear. But, now this fool doesn't know what to think.

Help!

Dan

 

[chiefalen]

Re: Shift Interrupter adjustment

It's for shifting out of gear not into gear. Your lower cable stretched, and needs replacement. Common problem.

 

[kghost]

Re: Shift Interrupter adjustment

Here is the proceedure to adjust the shift cables.

If you were racheting when shifting into gear either your cable stretched or the U shaped shift link in the gimbal housing, the U has too much slop (usually caused by not putting shift control into forward and trying to remove outdrive.

Anyway there are tests that would tell you if the cable is bad but to difficult to type out here but in general if you remove the shift control cable from the shift bracket, shift the control handle to full forward/wide open throttle and make a mark on the cable end, now go full reverse and repeat. Measure distance between marks, (2 7/8" to 3 1/8") any more and replace the control cable.

SHort cable measurement test, remove short cable from shift bracket, push all the way in and spin prop by hand until full forward is made. Make a mark on shift cable end where the plastic stops over the metal.
Now with someone holding the prop from spinning pull the cable end out with two fingers, as soon as resistance is felt mark the inner cable where the plastic cable end ends. Now measure between the marks,
The measurement should be if I remember correctly 1/2 " to 9/16". any more and the cable or linkage is bad.


Shift Adjustment:

Trim out drive up 2 inches from all the way down.
Take keys out of ignition!!!!!!!!!!!
Have a second person stand at the prop.
You, remove the short shift cable from the shift bracket.
After the cable has been removed, push the plastic cable end all the way in and hold in place while prop is being spun C’Clockwise..
Have second person rotate prop counter clock wise until the prop is fully engaged and wont turn anymore. Maintain light effort on shift cable plastic end pushing it to keep forward engaged.

Measure the distance from the center of the brass trunion to the center of the round mounting hole in the plastic end. Adjust trunion to make that distance 6 inches. no more no less! In cases where the shift cable is old but still works well you can adjust this dimension to 5 15/16”. NO MORE.

Put shift control handle in forward FULL throttle position.
Remove the control shift cable from shift bracket at this time.

Install short shift cable back onto bracket at this time.

Take the shift control cable and adjust the trunion so it fits perfectly back into the shift bracket.
Before installing it turn the brass trunion 4 complete turns away from the plastic end and reinstall into shift bracket.

Now put shift control handle in the neutral position.
Have second person spin prop, it should spin freely.
Put shift control into the forward detent position at ~ 10:00 position. NO FUTHER.
Have the second person rotate the prop counter clockwise. You should have solid engagement with no ability to continue to turn the prop.

Now shift back into neutral. Prop should spin freely with no clacking or clunking.

Now shift to reverse to the 2:00 o’clock position detent NO FURTHER!!

Have the second person spin the prop clockwise.

If you have positive engagement with no clunking or jumping out of engagement, you are done.

If it does not fully engage into reverse than look at the shift bracket where the short shift cable mounts and there is a slot. Loosen the 7/16 hex that is touching the bracket and move the stud so you are pulling the short cable.

Try this and retest in water under load.

 

[bondo]

the position of the interrupter will close (ground the coil), with the commander pushed forward or backward...weather running or not. Right? What good is that?

Ayuh,... The switch should stay centered, 'n not move at All,...
Except when shifting Out of gear, 'n Only in the water..

If it's doing othewise,..
As Chief said, your lower shift cable is Junk, 'n needs Replacing...

 

[chiefalen]

See when adjusted correctly all the years in use they just don't go out of adjustment the cable goes the end goes corrosion never sleeps.

Get the oem cable it's worth the few extra bucks.