Mercruiser 165 transom plate/outdrive

[83mulligan]

I'm removing the transom in my boat. It appears to be 1 3/4" at the outdrive hole. My plan originally was to replace the transom with two sheets of 3/4" for a total thickness of 1 1/2". Does anyone know the tolerances on this transom plate/outdrive setup? Should I maybe just throw in another 1/4" sheet between the two 3/4" pieces?

 

[Fishermark]

Re: Mercruiser 165 transom plate/outdrive

Mercruiser calls for a transom thickness of between 51-57mm (2 - 2 1/4 inches).

 

[83mulligan]

Re: Mercruiser 165 transom plate/outdrive

Thanks mark, guess I'll need that 1/4" sheet in there.

 

[Fishermark]

Re: Mercruiser 165 transom plate/outdrive

You might double check the total thickness of the three pieces combined - it doesn't sound like it will be even 2" thick with what you have planned.

 

[83mulligan]

Re: Mercruiser 165 transom plate/outdrive

I used a mic on the outer transom glass and it was between .26" and .31" in the places i checked. So, with 1 3/4" of ply and a couple layers of 1708 biax, i'm right there, no?

 

[Don S]

Re: Mercruiser 165 transom plate/outdrive

 

[83mulligan]

Re: Mercruiser 165 transom plate/outdrive

Thanks Don. That doesn't really answer the question of whether "transom thickness" includes just A or A, B, C combined.

 

[Fishermark]

Re: Mercruiser 165 transom plate/outdrive

"A" is the total thickness - and your's is not thick enough. "B" and "C" relate to the amount of variation of "flatness" allowed. Has nothing to do with overall thickness.

 

[Don S]

Re: Mercruiser 165 transom plate/outdrive

All 3 have to happen at the same time.

 

[83mulligan]

Re: Mercruiser 165 transom plate/outdrive

Ok, i see now what a, b, and c represent.

Fishermark. 3/4 + 3/4 + 1/4 ply = 1 3/4" plywood.

1 3/4" plywood + .25 to .31 outer skin = 2.0" to 2.06"

Plus the thickness of two layers of 1708 biax.

am i missing something here? You said its not thick enough.

 

[Don S]

Re: Mercruiser 165 transom plate/outdrive

3/4 plywood is NOT 3/4 thick.

What you need to do is post this over in the restoration forum. Lots of experience fiberglassing and building transoms over there. This forum is for engines and drives.

 

[Fishermark]

Re: Mercruiser 165 transom plate/outdrive

Fishermark. ..... You said its not thick enough.

Actually I just said to double check the actual thickness of what you have planned. I didn't "think" it would be thick enough - but you can measure and see! But don is right - better to post in the restoration forum. I have a new project I am about to start myself and will be posting there soon.

 

[APPALOOSA2]

Re: Mercruiser 165 transom plate/outdrive

I know on my Starcraft Aluminum from factory is 1 1/2 wood and they used a 1/2 thick piece just on the transom plate about 10" wider just around the transom cutout.

 

[83mulligan]

Re: Mercruiser 165 transom plate/outdrive

Actually I just said to double check the actual thickness of what you have planned. I didn't "think" it would be thick enough - but you can measure and see! But don is right - better to post in the restoration forum. I have a new project I am about to start myself and will be posting there soon.

Mark, look forward to seeing your thread over there. Of course I'll check, that's why I asked, lol.