Twin Screws - Stbrd Eng Dies When In Gear

[lv2bunderwater]

Hello all,

I tried to take my new to me boat out for the first time yesterday and the starboard engine dies when I put it into gear. A guy watching me trying to pull her back into the slip with one drive mentioned that I should have it looked at. I can't decide if I should attempt to fix it myself or just have the mechanic at the marina troubleshoot it. I let the same mechanic put new water pumps on the drives while I watched and I felt like an idiot for not doing it myself.

What do you guys think?

Thanks!

 

[Hampton]

Hello all,



What do you guys think?

Thanks!

Above all else, do no harm. If you're not going to do any damage, give it a try!

 

[Lazy Daze]

Neutral cut-out switch?

I'm not super familiar with the older stuff, but I remember fixing my dad's '86 V-8 when it did the same thing. I'll try my best to explain (it was a while ago).

On the engine, look where the shift cable does it's shifting. There will be a "micro-switch" there that engages/disengages when shifting gears. The idea is that it kills the engine for just a brief second to help make shifting easier. On my dad's, it was staying engaged. I bent the tab to make it work.

It's been so long, I'm sorry I can't be more specific. But, I think if you take some time and look at it, you'll be able to figure out what I mean. 'Course, that's assuming this is your problem.

 

[Jimmy Buoy]

Alpha I drives have a "shift interrupt" system. Basically as you go from neutral to either forward or reverse, the shifter engages a ignition shut off point (just for a split second) so that the engine slows down while the gears are being engaged. It doesn't stop the engine long enough to stall (usually). Kind of like switching your ignition key off then on quickly while idling in neutral - it wont stall the motor, just like a "hickup" of sorts.

Your shifter cables may be out of adjustment therefore allowing the shift inturrupt happen just after the gears engage - which will stall the motor with the torque from the prop turning in the water. :smt101

I've personally never had an alpha, just a Bravo I which had heavier gears and didn't require the engine to slow down prior to "crunching" into gear. If the Alpha did that it would chew up the gears (from what I've heard):smt009

I'd take a look at adjusting the cables so the interrupt point happens just before going into gear. Good luck!:grin:

 

[lv2bunderwater]

Thanks guys! That sounds pretty straight forward. I will look at it tonight and see if I can adjust the shift cables. I need to disconnect the cables anyway for inspection and to see if the shift handles need lubrication.

I'm enjoying the learning curve. Knowing where everything goes on a new to me boat makes a difference when you are out on the water.

Have a good day!

 

[EKM]

When it happened on my older boats, it was time to replace the cable. Once it gets sticky, the extra pressure pulls in the reverse lock out...this is on a Mercruiser OD. On a Mercruiser drive, you can see the switch with the flame arrester off and can see if the microswitch is being triggered. I would check this before attempting adjustments.

Sometimes you can get an extra season out of it with an adjustment...but you may get stuck somewhere.
Good luck....

 

[Kameroo]

2nd on the shift cables out of adjustment.