Reverse and Forward gears too far apart in Alpha One???

brauenbuehler

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Joined
Apr 17, 2020
Messages
3
Hi All, new to the forum and the world of boat repair!

I have a 1981 Glastron with a Mercruiser 470 and a Gen 1 Alpha one outdrive. When shifting the boat, it will either go into forward or reverse but not both. It almost seems like the shifter doesn't have enough throw to engage both gears or that the gears are too far apart. I've adjusted that bronze trunnion in the rear in a lot of different ways and can only get it so it almost engages both gears but doesn't actually get into either.

We just finished up checking the dog gear, forward and reverse gears in the lower unit and they all seem to be in decent shape and the spool has little play (nothing bad enough to be causing our problem).

Has anyone had this problem or think they know how to solve it? I appreciate any advice you've got for me. We've done a lot to the boat and this is the last major item to check off the list!
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
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Jul 23, 2011
Messages
50,313
First....... Welcome aboard

Sedond, when was the last time you adjusted the lower shift cable or replaced it?
 

brauenbuehler

Recruit
Joined
Apr 17, 2020
Messages
3
First....... Welcome aboard

Sedond, when was the last time you adjusted the lower shift cable or replaced it?

Thanks! We got this boat for cheap at an auction a couple years ago and have no history to it. As far as I know, the cable hasn't ever been replaced. Would this cause the problem?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,313
age. the cable has a life expectancy of 15 years tops.... they stretch

buy a new cable

I also suggest you read up on all the issues with the 470 motor

HX upgrade
Alternator upgrade
Head Gaskets
Cam seals and speedy sleeves

and since you know nothing of prior maintenance, I would assume nothing has been done, and do everything
  • alignment (should be done annually or every 50 hours of service, which ever occurs first)
  • check the u-joints (should be done annually or every 50 hours of service, which ever occurs first)
  • bellows normally last only 5 years. (inspection should be done annually or every 50 hours of service, which ever occurs first)
  • gimbal bearing(inspection should be done annually or every 50 hours of service, which ever occurs first)
  • raw water pump kitnormally last only 5 years. (inspection should be done annually or every 50 hours of service, which ever occurs first)
  • gear oil change (should be done annually or every 50 hours of service, which ever occurs first)
  • engine oil change (should be done annually or every 50 hours of service, which ever occurs first)
  • cooling system service
  • cooling system pressure check
  • compression check
  • fuel system service
  • points service (should be done annually or every 50 hours of service, which ever occurs first)
  • pull the distributor and check the shaft bushings ($5 part from napa)
 

brauenbuehler

Recruit
Joined
Apr 17, 2020
Messages
3
age. the cable has a life expectancy of 15 years tops.... they stretch

buy a new cable

I also suggest you read up on all the issues with the 470 motor

HX upgrade
Alternator upgrade
Head Gaskets
Cam seals and speedy sleeves

and since you know nothing of prior maintenance, I would assume nothing has been done, and do everything
  • alignment (should be done annually or every 50 hours of service, which ever occurs first)
  • check the u-joints (should be done annually or every 50 hours of service, which ever occurs first)
  • bellows normally last only 5 years. (inspection should be done annually or every 50 hours of service, which ever occurs first)
  • gimbal bearing(inspection should be done annually or every 50 hours of service, which ever occurs first)
  • raw water pump kitnormally last only 5 years. (inspection should be done annually or every 50 hours of service, which ever occurs first)
  • gear oil change (should be done annually or every 50 hours of service, which ever occurs first)
  • engine oil change (should be done annually or every 50 hours of service, which ever occurs first)
  • cooling system service
  • cooling system pressure check
  • compression check
  • fuel system service
  • points service (should be done annually or every 50 hours of service, which ever occurs first)
  • pull the distributor and check the shaft bushings ($5 part from napa)

Wow. Great bunch of info here. I'll have to look into changing that cable. Seems pretty difficult to access. Might have to pull the engine (?) Do you have any advice here? I'm assuming the cable goes into the upper section of the outdrive. Do I need any kind of alignment tool to correctly do the job?
 

nola mike

Vice Admiral
Joined
Apr 22, 2009
Messages
5,443
I'd check the cable before replacing it. achris has a good youtube vid on how to adjust it, and how to check the play in it. First thing, disconnect the cable and try to move it. It should have *very* little resistance.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,348
I would make sure the lower shift correctly first. Remove the drive , turn the brass shoe fully clockwise untill the prop is locked. Shoe MUST be at 12:00 If past 12 you have a shift spool issue. We just finished up checking the dog gear, forward and reverse gears in the lower unit and they all seem to be in decent shape and the spool has little play (nothing bad enough to be causing our problem) You physically open up the lower unit to inspect these items?
 
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