instructions for converting to twin mercruiser engines?

[lime4x4]

I remember seeing some where instruction on how to install twin mercruiser engines and drives. Since i have to redo my transom,stringers and bulk heads. I'm seriously thinking about making it into a twin engine boat. Which by the way was option for my boat. Alot depends on if i can find a donor boat for the parts.

 

[Bondo]

Re: instructions for converting to twin mercruiser engines?

Ayuh,... I donno exactly what you're lookin' for,...
Mounting Twins means glassing in the holes, cutting 2 more,+ adding mounting points for everything...
Pretty much the same as mounting a Single, only Twice the work...

 

[lime4x4]

Re: instructions for converting to twin mercruiser engines?

Yeah i know about glassing in the current drive cut out. The instruction told u how to find the center line of the boat and then measure from there for currect placement of the engines (cutouts)

 

[Bondo]

Re: instructions for converting to twin mercruiser engines?

Ayuh,... The Keel Line is the center of the hull, or atleast what Matters....

As for how Wide,... Wider is Better,... Both from a handling point of view, as well as servicing the motors...

The few installation manuals I have recommend an engine bay minimum width of 32"...
SBC Merc motors are listed at 29" over all,... BBCs are listed at 32" over all...

 

[lime4x4]

Re: instructions for converting to twin mercruiser engines?

My engine bay can handle 2 chevy small blocks no problem there. But don't they still have to be placed just right? U don't want the drive too low in the water and u don't want them too high either.

 

[Bondo]

Re: instructions for converting to twin mercruiser engines?

But don't they still have to be placed just right? U don't want the drive too low in the water and u don't want them too high either.

Ayuh,... Absolutely...Same rules apply...

 

[lime4x4]

Re: instructions for converting to twin mercruiser engines?

That's what i'm trying to find. The proper placement of the drives

 

[Bondo]

Re: instructions for converting to twin mercruiser engines?

Ayuh,...
Short story goes,....
Establish the Keel Line....
Establish how far off the Keel line you want the drives/ motors...
Establish the water flow/ path/ level where the centerline of the drives will be...
Set the crankshaft centerline/ point on the transom using the before established Info...
Then start drilling Holes... Keeping both sides Plumb/ Squared to the Keel Line....

Again,... Same basic rules apply, Single, vs. Twins, vs. Triples...

Also remember,...
Once the transom assembleies are bolted in,...
Not only do they determine the Height of the Outdrives,...
They determine Exactly where the motors must live, per the gimbel bearing alignment.....