Alpha 1 Shift Shaft?

beckerdg

Petty Officer 2nd Class
Joined
Sep 9, 2002
Messages
147
On a routine check I found evidence of leakage into the gear case of my Alpha drive. I pulled it and took it to the shop to have it pressure tested and resealed. They found it leaking around the prop shaft and resealed. The mechanic said he had a time getting it resealed due to some pitting on the housing and he had to do the job several times. (cost me extra in labor) Exterior if the outdrive is fairly clean.<br /><br />That's not my issue though. I went to put the drive on and found that the shift shaft has about a half inch of play in it (vertical) and no longer sits up high enough to engage the slot in the shift lever on the bell housing.<br /><br />I read the manual closely when I put it on, throttle in forward gear, drive in gear to index the splines to match the engine coupler, slip the shift slide into the slot on the drive and verified the shift coupler and shaft were aligned. The drive slipped into place with very little pressure mostly just some shaking back and forth to get things lined up. Slipped into place with about an eighth inch gap which I tighted up with the mounting bolts. Started the engine on the hose and tested the shifting nothing. Went back and looked under the boat at the shift coupling on the drive and the shift shaft was too low to engage the shift lever on the bell housing.<br /><br />So the question is did I damage it in the removal/installation process, or is it something the shop could have done? Thing is I don't see any scratching or marring on the shift shaft or slot that would indicate I did not have them aligned though I also doubt the shop was working in that area, but don't know much about the work to reseal the hub. The shift shaft does move the drive in and out of gear in both directions. What holds the shaft at the proper level? Is it something simple, or do I go back to the shop?
 

airman

Petty Officer 1st Class
Joined
Aug 9, 2003
Messages
332
Re: Alpha 1 Shift Shaft?

I'm not quite sure if we have the same drive but maybe this will help... 1982 Merc 470/Alpha drive. It's off the boat right now and I measured one and three quarter inces from the casting to the top of the shift shaft. I can pull it up an extra 1/8" but that's it.
 

crazy charlie

Vice Admiral
Joined
May 22, 2003
Messages
5,581
Re: Alpha 1 Shift Shaft?

First make sure they gave you the right drive back.The shift arm in the upper just sits in the hole with a cotter pin holding it on.It usually has plenty of play.It could have fell out when they were working on it and it was replaced with the wrong one.The arm slides over the shaft when the upper and lower are put together.There is a chance that the arm did not slide into the grooves when it was put back together and is now jammed together.Either way you should begin to drop the lower.You can inch it down as far as you can without taking it off.This will expose the shaft in the lower and will free up the arm in the upper.It is also possible that when the upper and lower were put back together,the lower was in neutral instead of fwd.Too many possibilities!!Were you able to lock the drive in fwd before you slid it on???? Charlie
 

beckerdg

Petty Officer 2nd Class
Joined
Sep 9, 2002
Messages
147
Re: Alpha 1 Shift Shaft?

Definately my drive. <br /><br />I saw from the exploded view of the drive there was a pin holding the shift shaft that is exposed to the real shift shaft that goes into the lower. As you said that may have come loose or was broken.<br /><br />The drive shifts into forward and reverse fine. I had to put it in forward to index the splines with the engine coupler and align with the slot for the shift shaft. The shift arm just sits about a half inch too low and will slide up about a half inch if I lift up on it. No other play that seems abnormal. If the pin is out or broken is that very hard to replace?
 

crazy charlie

Vice Admiral
Joined
May 22, 2003
Messages
5,581
Re: Alpha 1 Shift Shaft?

The arm itself is only a 20-30$ part.It looks like it just drops through the hole.I have a spare alpha apart,I will look at it to see if I can make sense of what you are stating. Charlie
 

beckerdg

Petty Officer 2nd Class
Joined
Sep 9, 2002
Messages
147
Re: Alpha 1 Shift Shaft?

Thanks but I did some reading in my manual and broke down and split the upper and lower housings and took a look. <br />Found the problem to be the shop missed an important step. There was supposed to be a stainless washer installed above the bushing of the lower shift shaft and below the shift arm that comes through the upper housing. It was missing. So the upper shaft was riding on the rubber bushing of the lower shaft. The way the washer would fit it would raise it a little over a quarter inch and keep it off the rubber bushing and make it high enough to fit the slot on the bell housing.<br />Guess I will give the shop a call tomorrow and ask for the washer, and a another seal kit for the bell housing. Doubt I will get any compensation for my time...
 

crazy charlie

Vice Admiral
Joined
May 22, 2003
Messages
5,581
Re: Alpha 1 Shift Shaft?

Wow!!!!!!!!!what a pain!!!!!! Good that you were able to find the cause.It is good to be familiar with the components.I thought of that but when you stated how far the arm was from the slot,I did not think a washer would make that much difference so I passed on that possibility.Did they give you the drive back in 1 piece or 2 halves????? Charlie
 

Capt Ken

Commander
Joined
Jul 30, 2002
Messages
2,270
Re: Alpha 1 Shift Shaft?

Actually there should be a rubber washer under the SS washer.
 

beckerdg

Petty Officer 2nd Class
Joined
Sep 9, 2002
Messages
147
Re: Alpha 1 Shift Shaft?

I took it to them fully assembled for the reseal, and they returned it fully assembled minus the washer. I'll ask about the rubber washer too. The mercruiser book did not mention a rubber washer, just the stainless one and the rubber bushing that provides the seal on the lower shift shaft. Thanks.
 
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