Gear Ratio

[dk6164]

I trashed my lower unit over the weekend. Cracked the case and the driveshaft snapped at the O ring groove. I've been looking for a new (used) outdrive or lower. I have a Alpha 1 behind a 3.0 1.98 gear ratio. I was wondering how bad it would be to put a 1.84 on it? Maybe drop down on the prop pitch? Do you think it's do-able or should I stick with a 1.98<br /><br />Thanks for the help.

 

[Haut Medoc]

Re: Gear Ratio

I think it would make your engine lug, by making it work too hard. You could change diameter/pitch, but it would never be really right. I say stick with the original gearing......JK

 

[dk6164]

Re: Gear Ratio

Thanks for the reply.I can't decide wheather to buy just the lower (nothing but a hole where the skeg used to be) or a matched set. I've read in some old posts where the guys bought the lower and wish later that they hadn't. I'm not very good at shimming and setting gear tolarences (sp)<br /><br />Thanks again

 

[Laddies]

Re: Gear Ratio

If you buy a complete lower it does not require any shiming it's a unbolt and slid the new one in, we change lowers all the time and never heard of a problem

 

[rodbolt]

Re: Gear Ratio

most all the alpha gear cases for production use had the same ratio. the final drive ratio is determined by the gear set in the driveshaft housing.<br /> I am with laddies. if the upper is not damaged replace the lower and go play.

 

[dk6164]

Re: Gear Ratio

How do I go about getting the spline out of the upper gear housing without pulling the top housing apart. Or do I just have to slide the upper driveshaft out a little and pull the middle drive shaft out? (probably not the correct terminology but I hope you know what I mean)

 

[whywhyzed]

Re: Gear Ratio

The fact that it IS a spline is why you don't have to take the upper apart. Splines slide apart.<br />A service manual will have pictures and the procedure...

 

[Don S]

Re: Gear Ratio

Do you have an Alpha I or an Alpha I Gen II drive. The Gen II started into production in 91, so you could have either one on your boat.

 

[dk6164]

Re: Gear Ratio

I have the Gen 1 and the only thing about it is where it snapped it looks as though I will have to get the upper part of the shaft out in order to get the spline out of the coupler. It broke so cleanly that you have to really look at it to even tell it snapped! Right at the bottom of the o-ring groove.<br />Again-please excuse the terminology, I'm still learning!

 

[dk6164]

Re: Gear Ratio

DUH- A magnet retrieval tool- snag out the o-ring-a little jiggle and out it came. Talk about feeling stupid. The only good thing is that while I had the cap off I counted the teeth. I have a 1.84 ratio behind a 3.0. Might explain why my WOT is just barely 4200!