400 vs 800 - interchangeable?

[walk-on]

I have a broken 400 outdrive and an opportunity to pick up an 800 outdrive. I don't yet know what exactly is broken on the 400. Are there any parts that are interchangeable between the two? What parts are not interchangeable?

Thanks!

 

[sYnOnYx]

Re: 400 vs 800 - interchangeable?

Short answer.... No.

The 800 gear ratios are different than the 400.

 

[walk-on]

Re: 400 vs 800 - interchangeable?

The bearing carrier drive shaft and water pump drive shaft are bad on the 400. The 400 is an '83 and it appears that the 800 in the '78 - '85 range used the same shafts, as per the parts manual. The other gears look good.

 

[Howard Sterndrive]

Re: 400 vs 800 - interchangeable?

generally, the only thing different in the uppers would be the gearset. You can use the shafts out of the 800
There are a few special tools required to set proper backlash and preload per the manual

If someone rebuilt a lot of transmissions and differentials, they might be able to set it up without the tooling.

count gearteeth and see how different they are. If you know the application of the 800, you can check it's overall gear ratio compared to the 400 -

or sell what you have and buy what you need.