alpha one outdrive gears stripped????

[freddieusa]

I pulled my alpha one outdrive off my chaparral with the 454 magnum engine. It was locked up, but the engine turned fine after I pulled it. I got the u joint assembly (coming from the engine) to turn by hand, but it is very rough, like some grit in the gears. When I turn the u joint assembly the drive shaft that goes down to the lower unit does not turn. If i turn the shift lever to one side or the other, the prop will lock in gear, but extremely hard to turn. It seems like it would be a bad gear assembly in the upper unit, but I am wondering if I might have some problems in the lower unit as well. Also, the shifter "shaft" seems to move up and down about 1/4 to 1/2 inch. Is that amount of play normal? I have never worked on an outdrive before so I am trying to minimize what I take apart so I have less chance of screwing anything up. Any help would be really appreciated!!

 

[dingdongs]

Re: alpha one outdrive gears stripped????

time for a new one;look here; www.sterndrive.cc

 

[achris]

Re: alpha one outdrive gears stripped????

I pulled my [size=+1]alpha one outdrive[/size] off my chaparral with the [size=+1]454 magnum engine. [/size] It was locked up, but the engine turned fine after I pulled it. I got the u joint assembly (coming from the engine) to turn by hand, but it is very rough, like some grit in the gears. When I turn the u joint assembly the drive shaft that goes down to the lower unit does not turn. If i turn the shift lever to one side or the other, the prop will lock in gear, but extremely hard to turn. It seems like it would be a bad gear assembly in the upper unit, but I am wondering if I might have some problems in the lower unit as well. Also, the shifter "shaft" seems to move up and down about 1/4 to 1/2 inch. Is that amount of play normal? I have never worked on an outdrive before so I am trying to minimize what I take apart so I have less chance of screwing anything up. Any help would be really appreciated!!

There's your problem... Time to bite the big one and cop for a Bravo set-up....

 

[Struc]

Re: alpha one outdrive gears stripped????

Shifter shaft movement is pretty normal.

However, I agree that your unit is toast. If you drain the gear oil, pull the top off, I'd guess you'll see your problem right there.

While expensive, replacement is the only way to go. Rebuilding these things takes expensive special tools, and they add up to nearly the cost of a whole new unit when you factor in replacement parts. Maybe if you're lucky you can just buy an upper unit - hard to say for sure from across the interweb.

 

[freddieusa]

Re: alpha one outdrive gears stripped????

So I am thinking about just replacing the upper unit, but i dont know what the ratio is. Is there a way to tell or should I go with a specific ratio with the 454 engine? Also, if I can find a bravo unit for a reasonable price, will it match up to the alpha equipment that is still on the boat?

 

[Bondo]

Re: alpha one outdrive gears stripped????

So I am thinking about just replacing the upper unit, but i dont know what the ratio is. Is there a way to tell or should I go with a specific ratio with the 454 engine? Also, if I can find a bravo unit for a reasonable price, will it match up to the alpha equipment that is still on the boat?

Ayuh,... If ya replace Just the Upper, you can expect the lower to puke in a day or two,...
All the ground up gears from the upper, are now in the lower....

The 454 used 1.32:1 gears, which are now NLA... yer only choice is 1.50:1....

Yer Best choice is a Complete SEI drive....

No,.... A Bravo will Not fit yer Alpha 1 transom...

 

[freddieusa]

Re: alpha one outdrive gears stripped????

I really appreciate all the help. I did pull the top off and sure enough the gears are chewed up. Right now I am going to try to find a inexpensive used outdrive. Just a couple of more questions... How can I tell what the ratio is on an outdrive? Are there numbers stamped somewhere on the outside? Also, if I can find one, will it just mount up or will I need to do any adjusting or aligning?

 

[Struc]

Re: alpha one outdrive gears stripped????

I'm pretty sure it is stamped someplace, although I don't remember exactly where. I think on the port side just under the sticker. I'm sure one of the experts will jump in with one of the 1000 pictures they keep handy for these types of questions.

As far as adjusting or aligning - technically there is nothing you have to do. However, while you have it off, it might not be a bad idea to check the engine alignment.

 

[achris]

Re: alpha one outdrive gears stripped????

Checking alignment: http://youtu.be/w118LGsYgY4

 

[Fishermark]

Re: alpha one outdrive gears stripped????

You can always put it in gear and turn the driveshaft and count the revolutions of the prop shaft to determine the ratio.

 

[TilliamWe]

Re: alpha one outdrive gears stripped????

Right now I am going to try to find a inexpensive used outdrive...

BAD idea. Your 454 Magnum in front of an Alpha was only done a few years, until Mercruiser could get the Bravo series drive developed. A used drive will NOT last.

For under $1500 you will get a BRAND NEW SEI drive (right here on iboats) and I think they'll even still offer the 3 year no-fault warranty, even behind a 454. It's a no brainer. The "only" problem you'll have is that you currently have a 1.32 ratio, and you can't get that anymore. You'll have to go to a 1.5 (or 1.47 nowadays), and you'll need a new prop. You're prop pitch will go up in number, probably about 2 inches.