What is the difference between these two outdrives

[roscottjr]

I have two outdrives and I am not sure what the difference is. The one with the prop is on my 1987 Wellcraft with 3.0 140hp 4cylinder. The other outdrive came off a 1985 Chaparral with a 228 5.0 engine. I noticed the skegs are different but what is different between the two drives? Are the lower units interchangeable with the upper? The lower unit with the prop has a piece broken off where the fin is bolted. I dont believe it hurts anything but I would like to use the other lower on the boat if possible. Both drives have excellent looking gear oil and appear to be in great condition.

Also, the drive from the Chaparral does not have a trim tab, only a flat plate. Is this because the boat had power steering?

 

[achris]

Re: What is the difference between these two outdrives

Uppers and lowers are interchangeable. The bottom picture has a Alpha 1 lower.

The overall drive ratio is determined by the upper. 140 has a gear ratio of 1.98:1 and the V8 has a ratio of 1.50:1

Flat anode is for power steering.

Piece broken off the anit-cav plate is because of the horrid piece of plastic you have bolted to it....

Bottom line.... swap the lowers with out a problem.

Chris........

 

[roscottjr]

Re: What is the difference between these two outdrives

LOL. Yes that is a horrid piece of plastic bolted to it. It was already there when I got the boat. I was going to remove it and that is when I found out the cavitation plate was broken.

What type of lower is in the top picture?

As you can see the prop has a little damage as well. It is an alluminum 14 X 19 prop. I have a stainless steel 14 1/2 X 19 Ballistic prop. What difference will this stainless steel prop bake to the boat?

 

[tractoman]

Re: What is the difference between these two outdrives

I'd be looking for a replacement prop while your at it.

 

[roscottjr]

Re: What is the difference between these two outdrives

I'd be looking for a replacement prop while your at it.

I already planned on that as well. lol

 

[Fishermark]

Re: What is the difference between these two outdrives

The bottom picture has a Alpha 1 lower.

Now I'm confused!

I thought the gen II had the swept back skeg like the lower picture, as opposed to the Alpha which goes straight down.

If the bottom pic is in fact a Gen II, then that lower will not work with an Alpha. (But - that's IF it is a Gen II - if they are both Alphas, then I stand corrected!)

 

[Don S]

Re: What is the difference between these two outdrives

It's not a Gen II lower, you can't put a Gen II lower on an older Alpha, and that upper is not a Gen II.
My guess is the skeg got replaced and ended up swept back a bit.

 

[Fishermark]

Re: What is the difference between these two outdrives

My guess is the skeg got replaced and ended up swept back a bit.

I guess that would explain it. I knew it didn't look right!

 

[roscottjr]

Re: What is the difference between these two outdrives

Ok, so from what I understand I can take the lower in the second pic and put it on the upper in the first pic and the gears in both lower units are the same. From what I understand the gears in the uppers are different.

Now my question is, the boat currently has a 14 X 19 prop that obviously needs replaceing. I have a 14 1/2 X 19 Stainless Steel Ballistic prop, will this SS prop make any noticable difference in the way the boat runs? According to iboats this SS prop in this size is available for this boat. We will be cruising as well as pulling the kids on a tube a kneeboard and also a few adults on the kneeboard as well.

Also, aside from an impeller, are there any parts I will need in order to switch the powers around? Anyone have the part numbers for any parts I may need as well as part numbers for seal kits for when I may need those?

 

[frank246]

Re: What is the difference between these two outdrives

Still it is an odd lower in the 2nd pic (gen2).
Is it running and are the side thread studs missing or is it just the picture?
Beside the impeller youll need an new quad o ring that goes in between the lower and upper oil passage.

 

[roscottjr]

Re: What is the difference between these two outdrives

Also, assuming the skeg was replaced in the drive in the second pic, whoever replaced it did an excellent job. There are no signs of any replacement being done. Anything I should check on this skeg to be sure it wont cause any problems?

 

[roscottjr]

Re: What is the difference between these two outdrives

Still it is an odd lower in the 2nd pic (gen2).
Is it running and are the side thread studs missing or is it just the picture?
Beside the impeller youll need an new quad o ring that goes in between the lower and upper oil passage.

Both outdrives are in great shape. As far as I know nothing is missing and the outdrive in the second pic would bolt right up to the boat but from what I have found out the upper gears would be wrong. Cavitation plate has a piece broke in the first pic because of the stupid piece of plastic whale fin or whatever it is that the previous owner bolted on so I am wanting to switch the lowers.

Where are these side thread studs you are referring to?

 

[frank246]

Re: What is the difference between these two outdrives

Was the picture, they are there NM.