Alpha I shift cable adjustment, Reverse not fully engaged

[bartleyl]

'90 Mercruiser engine and drive out of boat to get some structural issues corrected. Reinstalled engine and after hooking up shift and control cables it appears its not fully engaging into reverse, forward is OK. (Had shift lever control out of boat as well)

Looked at FAQ article "I/O Shift Cutout Switch Adjustment" to get some information. Attempted the procedure but problem persists with not fully engaging in reverse.

I pulled the shift cable off the linkage and pushed the end in while turning prop counterclockwise and I reach a point where prop stops so I assume Forward is OK. When I turn the prop clockwise and move the end of the shift cable out I never reach a point where the prop stops, I get a ratcheting sound like the gears are not fully engaging. Any ideas what to look at next ?

 

[Haut Medoc]

Re: Alpha I shift cable adjustment, Reverse not fully engaged

Was it OK before?.....
Pull the drive & see if it will lock in reverse......
You may just need a new cable......
There are other causes, but verify that the drive will go in reverse while off the boat.....​

 

[bartleyl]

Re: Alpha I shift cable adjustment, Reverse not fully engaged

Was it OK before?.....
Pull the drive & see if it will lock in reverse......
You may just need a new cable......
There are other causes, but verify that the drive will go in reverse while off the boat.....​

The drive was OK when removed, ie it worked correctly in forward and reverse.
I'll pull the drive back off and see it will engage in reverse.

 

[bartleyl]

Re: Alpha I shift cable adjustment, Reverse not fully engaged

Was it OK before?.....
Pull the drive & see if it will lock in reverse......
You may just need a new cable......
There are other causes, but verify that the drive will go in reverse while off the boat.....​

Once I pull the drive if I find the drive will go into reverse what would be the other possible causes?

Is there a way to check the shift cable? My observation is the cable doesn't extend far enough to engage reverse. Because the issue is one of the cable not extending far enough tells me the cable has not stretched and therefore its not a cable issue. I'm a novice with the cable's so please correct me if I'm incorrect with my logic.

 

[Bondo]

Re: Alpha I shift cable adjustment, Reverse not fully engaged

Once I pull the drive if I find the drive will go into reverse what would be the other possible causes?

Ayuh,.... The Shift Cable,...

If the Outer casing has a groove worn in it,... It Can't push as far,...

If you Don't Know the last time the cable was Replaced,....
Change the Lower Shift Cable,.....

 

[Haut Medoc]

Re: Alpha I shift cable adjustment, Reverse not fully engaged

Once I pull the drive if I find the drive will go into reverse what would be the other possible causes?

Is there a way to check the shift cable? My observation is the cable doesn't extend far enough to engage reverse. Because the issue is one of the cable not extending far enough tells me the cable has not stretched and therefore its not a cable issue. I'm a novice with the cable's so please correct me if I'm incorrect with my logic.

Other causes would be shift crank wear, shift spool wear, worn clutch......
I'm still betting on the cable......

 

[bartleyl]

Re: Alpha I shift cable adjustment, Reverse not fully engaged

Well, some checking.

I found I can shift the outdrive into gear if I reach up and move the shifting shaft at the coupler on the drive. This is the one that has to be aligned when you put the drive on.

I also found that the drive will go into reverse if I pull firmly on the shift cable while rotating the prop. So it will go into gear but only at the very end of the cable.

The inner cable moves freely so will replacing the cable solve the problem or is there an adjustment on the other end in the outdrive or something else?

 

[Haut Medoc]

Re: Alpha I shift cable adjustment, Reverse not fully engaged

Well, some checking.

I found I can shift the outdrive into gear if I reach up and move the shifting shaft at the coupler on the drive. This is the one that has to be aligned when you put the drive on.

I also found that the drive will go into reverse if I pull firmly on the shift cable while rotating the prop. So it will go into gear but only at the very end of the cable.

The inner cable moves freely so will replacing the cable solve the problem or is there an adjustment on the other end in the outdrive or something else?

There is no adjustment in or on the outdrive side of the cable.....
If you cannot adjust the 'barrel' nut to get reverse, then I suggest a new cable......
If a new cable doesn't work, there probably internal issues as I described above, ie wear on the clutch dogs, gears, shift spool, shift crank.......
At that point, the tools & techniques that are required for disassembly, inspection, parts & reassembly are best left to a professional......
A cheaper option would be to get a new SEI aftermarket lower gearcase for about $700.00 or so, bolt it on & go......

 

[bartleyl]

Re: Alpha I shift cable adjustment, Reverse not fully engaged

Last night I found another post regarding a shifting issue where the shifting linkage wasn't lining up right ..... pics helped http://forums.iboats.com/showthread.php?t=248958

I looked at mine and it wasn't as bad as in the thread but there was some slop. Tonight I had some helped so I pushed the lower shifter rod up gently then had my stooly pull on the shift cable while I turned the prop shaft cw, reverse engaged as expected.

I pulled the lower drive off and found the stainless washer was there but it was caved in a bit causing the shift rod to ride slightly lower than optimal. I straightened the stainless washer, flipped it over and reinstalled the lower drive unit.

I adjusted the cable and now have both forward and reverse engaging. Reverse still engages at the end of the cable throw but I suspect its always been like that. Need to check it with muffs in the driveway then hopefully at the lake this weekend.