Aligning twins

[speakrdude]

Seems like I've seen this question somewhere before but wasn't paying attention.

I about to put the finishing touches on my transom rebuild (weekend project) and have a question concerning drives alignment.
The rig is an 88 300 DA with Gen II's.
Should they be dead center with respect to each other? Toe in? Toe out? How much?

Thanks all!

 

[speakrdude]

(Dont anyone say a training bra either)

 

[KC_Sundancer]

Seems like I've seen this question somewhere before but wasn't paying attention.

I about to put the finishing touches on my transom rebuild (weekend project) and have a question concerning drives alignment.
The rig is an 88 300 DA with Gen II's.
Should they be dead center with respect to each other? Toe in? Toe out? How much?

Thanks all!

From my experience it depends on prop rotation. The idea is to have them running parallel under load.
If rotation is the same they should be set parallel.
From our racing day's we measured between the outdrive front edges and prop shaft centers.
If rotation is counter rotating as our race boat was we set them 1/8" different between the front edge and prop shaft centerlines.
Props turning (port) counter clockwise and (starboard) clockwise prop shafts were set 1/8 narrower.
Keep in mind this was with a tie bar link and hydraulic steering on Bravo's so there was no play and over 500 h.p. pushed through each drive.
Counter rotating with props turning out as stated above will cause the drives to want to spread away from each other under load. If there is any play in your steering you should probably measure with drives held apart to remove any slack (or same direction if same rotation set-up).
My thoughts and experience with your typical pleasure boat is as long as they are within 1/8" of parallel either way you will not notice a difference or cause any damage.

I Forgot to mention on our 270 DA, when I finished the transom rebuild, alignment was set at parallel since prop rotation is the same.

 

[speakrdude]

On this 300, the port drive is counter rotating. Sounds like parallel or 1/8", toe in. (Close enough)
Thanks as always for you help.

 

[rcon]

I've asked a similar question here before as I notice my alpha drives were toed in. Was told it is standard practice.

Have no technical details to offer tho.