Trying to make sense of my Shift interrupter

[Dirty Dawg]

Hello all I have a 2000 Sea Ray 5.0L MCM Mercruiser with a carb and a Alpha one Gen II stern drive. Last year we had major work done due to a frozen starter requiring the engine removal to allow access for its removal. (thanks to you all for helping diagnose the issue) This year after decommissioning I ran into some issues that were also plaguing the boat last year. The boat would almost always stall when shifting into reverse. No issues in forward.

So I was hoping it was a simple adjustment issue. Looked thru the forum for similar posts and info and I pulled out my service manual and followed the procedure for the remote control shift cable adjustment, but I ran into some issues.

Adjusting the cable forward was not an issue but when moving the shift into reverse the instructions advise to spin the prop shaft clockwise until the prop stops and the clutch engages. My prop continues to spin and will not engage the clutch (I am assuming). The other issue is that there does not seem to be enough play in the drive shift cable when I move into wide open throttle in reverse it results in the shift interrupter switch being activated and stalling the engine.

So what could be going on? I have read that some of these adjustments need to be done in the water to allow pressure on the prop to allow it to shift properly, so I am not sure if that is causing some issues in adjustments. Why will the prop not lock up in reverse as per the instructions? It seems to me that the drive shift cable is free and the inner cable is not binding but???? could it be the cause? If I need to replace the cable what is involved, how much of the drive needs to be removed? Can someone give me an estimate in the hours needed? Thanks as always Ike

 

[Bt Doctur]

Re: Trying to make sense of my Shift interrupter

you could have debris inside the slide preventing full travel
or the shift spool could be worn in the lower unit.

 

[Don S]

Re: Trying to make sense of my Shift interrupter

Disconnect the lower shift cable from the shift plate, then with the someone turning the prop by hand see if you can pull the inner cable of the lower shift cable by hand enough to get it into reverse.

 

[Dirty Dawg]

Re: Trying to make sense of my Shift interrupter

Thanks for the replies!!

Bt Doctur could be, I know when reassembling the drive there is a cable support tool to allow the assembly without interfering with the cable.
Don S I tried that and if I adjust the cables a certain way it goes into reverse fine but then I loose the forward movement completely and the interrupter kicks in on forward . It seems I can only get enough play to either for the replies r set it up in forward or reverse. There does not seem to be enough cable movement to allow for both. When I have it set up to allow full forward movement I can get the boat into reverse and it allows me to push the throttle all the way through full throttle but almost immediately as it gets into reverse the interrupter switch engages. I took the cable apart and oiled it at the shift assembly point and the inner cable is moving freely. The cable just does not seem to be "long enough" and it kicks in the interrupter switch . Ike

 

[Speakrdude]

Re: Trying to make sense of my Shift interrupter

This is the best advise I've seen.

Mercruiser Alpha Shift cable adjustment - YouTube

 

[Dirty Dawg]

Re: Trying to make sense of my Shift interrupter

Speakrdude, Great link thanks, unfortunately that is what I did and still getting the interrupter engaging on reverse. Any other thoughts if not it looks like the drive needs to come off. Can someone give me an estimate in shop time and maybe cost to replace/repair the drive cable? Thanks All

 

[Bt Doctur]

Re: Trying to make sense of my Shift interrupter

Depending on how you by the components shift cable kit W/ boot and mounting gasket or each part separately 60-100
About 2-3 hrs labor ASSUMING everything just comes off nicely and there is adequate room to work. When was the cable changed last?

 

[Dirty Dawg]

Re: Trying to make sense of my Shift interrupter

Well that at least to me is the disappointing part. Last year we had major work done to the boat, a failed an frozen starter required the engine to be removed. As part of that work there was a leak up into the shift cable from a leaking boot. It was supposed to be corrected and it appears that only the boot was replaced. Now I am not sure what is binding and where but the cable was not replaced and may be a few years old. I do not think it is the actual cable, I think it is getting jammed up some how. So there we are, I was hoping that it was simple but it appears to be more complicated. Ike

 

[indybleck]

Re: Trying to make sense of my Shift interrupter

Getting the shift cable and boot replaced along with drive bellows replaced, the mechanic told me he going to call it a reseal. Called me today with the damages, new boots cable and seals $500.00. That's at $85 an hour labor. That's just about what I was thinking. I used to do this stuff myself but the older I get I just don't want to do it any more so I work a little overtime and let someone else do it.

 

[Dirty Dawg]

Re: Trying to make sense of my Shift interrupter

Hmm I thought I posted a response??? Oh well it turns out that it was the shifter cable, some corrosion between the cable and the sleeve it moves back and forth in binding it just enough o engage the interrupter switch. Working fine now. On the upside I found a great mechanic to work with. Really nice and knowledgeable guy!!! Thanks again for all your help!! Ike