new transom/engine beds 23 Tsunami

[bigeasy1]

I just finished building and installing a new transom on my Tsunami project.I used two 3/4 pieces of marine fir plywood glued together with epoxy.

I laid up a couple layers of 1708 on the inside of the skin,then we glued in the plywood,and then we put three layers of 1708 on the inside face of the plywood.

The final thickness is approximately 2-1/8 inches,which is within the requirements for the Mercruiser (2 to 2-1/4).
I now have to tie the stringers back in,and replace the engine beds,(and eventually cut out the i.o. drive hole).

I have a question regarding the engine beds(short type of stringer)
What is the best wood to use?,.
iv'e thought of fir,or spruce,and even mahogany or cedar.I also gave some thought to pressure treated,and i know that the glass may not adhere to it,but the glass basically is just keeping them in place,so that may not be an issue.

I plan to put good limber holes in them,but also want to use something that will last.

The following pictures may show them better. In the last picture, "you can see where the engine beds have to be built.I have marked them in black lines."
Any reccomendations or thoughts would be appreciated.
Thanks all.

[1bayouboy]

What engine package are you planning to put in???

[jobu]

Sorry to bug you but could you take a look at my post "Any Help, alien modifications " under repair mods. and tell me if these things are motor beds too? I am at a loss. Thanks, joe

[bigeasy1]

Bayouboy,i'm almost positive it will be a Mercruiser 350 MAG 300hp MPI with a Bravo I OR II drive.I gave some thought to Volvo,but in the areas i fish mercruiser dealers and parts are much much easier to come by.

[abl1111]

Did the same job. Hope these pix tell a 1000 words. Keep up the great work. Your vision is happening ! Don't mind the huge i/o cavity, this boat had (2) i/o's and it was converted to (1) mercruiser.

[image][/image] [image][/image]

[bigeasy1]

Thanks abl1111,did you use the measurements from the mercruiser drawings to lay out the beds?.Also where did you buy your engine and drive?I was wondering if a pattern came with it for the outdrive cutout.
I spoke to the people at Bam in florida they seem to have good pricing.

[abl1111]

I had a buddy help me with this part ( he helped me with a lot of the finesse stuff ). He is a fiberglass guy and has done extensive refits before.

We used (2) 2x8, or 2x10's, I forget, and laminated them together - as well as screwing them together ( obviously they are completely glassed-in). The bottom of the motor beds were angled to exactly fit the contour of the hull - they snugged up against the chine in the hull too. We had to build a forward bulkhead for the motor beds to tie into, as the orig (2) motor layout did not have the same motor bed config.

With this design, it fit beautifully, although I did have to nick out and re-glass a small peice of motor bed to make room for the alternator pulley - it all looks factory or better.

The motor I bought, a Mag 350 w/ a Bravo 3, from a local mercruiser guy here on LI. He helped a lot, i.e. supplying the gimbal jig, and lots of advice and input. Best of all, I traded him the original (2) 4 cyl i/o's and drives for use of an inside garage/storage place where a lot of the resto happened over a winter. He was happy to get his hands on some old 'iron dukes' and I was happy to be rid of them and have a place to work.

If you have any questions, or want pix, I did document my whole resto, so if I can help I certainly will try ( I asked this board just about every question under the sun when I was doing my resto ).

# 1 thing learned: beer is the lube you need to truly do the job right... Good luck !

[1bayouboy]

I bought my package from BAM....350MAG MPI Horizon. There's an installation CD that's pretty detailed. There's also a drawing for the cutout. I was repowering so my cutout stayed the same without mods. I did have to rebuild the stringers, but I cut the tops off and recored them so I even kept the original mounting plate holes.

The biggest thing is to get the correct X dimension which controls the heaight of the transom assembly and drive. Once that's done, it would be best if you could get a jig to drill the transom assembly mounting holes and the cutout. Once the transom assembly is mounted, there's another jig that goes through the gimbal bearing and sits on the two engine mounts on the inside of the transom assembly which has extensions that show where the front engin mounts should be positioned. A friend who used to work in a Merc service dept told me how it worked. It's important to get the correct height on the front mounts so that the engine coupler will align with the gimbal bearing.

It be worth renting one or having a shop do that piece.

[bigeasy1]

Thanks all, i meant to say Bravo III ,not II "geesh" i do that all the time.