Transom structural question___Please take a look

[markj07]

I decided to take a peek at the inside of the transom of my, new to me, '92 Spectrum 1606. The area of the transom that the outboard is bolted to is solid but both outside edges of the transom have some rot starting. This is probably one of those dumb questions but...how important is this part of the transom to the integrity of the boat? Putting some weight on the outboard I do not see any flexing. I have not had this boat on the water.


Thanks,
Mark

 

[acwd]

The transom board is very important part of the structure of a boat. If it shows any rot and isnt solid I would replace it.

Steve

 

[lckstckn2smknbrls]

You want as much structural support as possible.

 

[markj07]

Here is a pick of the outside of the transom. If I replace the transom the top aluminum cap is one piece integrated with the engine well. Everything uses screws or rivets except the two red circles, those are welded to the transom. Does anyone have any suggestions on how to remove the top piece and tray together? I should be able to cut the weld and have it welded back together when finished.

 

[Ranchero50]

I would take the boat to a couple local welders and get their opinion on where you should cut it so it's easiest for them to weld it back together. Figure out which guy is genuinely interested in the work and go from there.

 

[huntinfool]

The outside of the transom doesn't bear any weight of the transom nor does it have much to do with the flex of the transom because of torque of the motor. However it does lend some support to the eye bolts and the gunnel. I've rebuilt numerous transoms and some that were much worse than yours.
Having said that, the fact that you do have rot in your transom only means that you're on borrowed time. How much, hard to say. Take a 1/4" drill bit and drill into the transom near the motor mounts. Don't drill all the way through, but into the wood a good bit. Check the shavings. Are they clean or are the dirty/dark, indicating rot. Are they wet? These clues will help you to know how bad it really is. If it is wet, its only a matter of time before it rots. If it is dirty/dark the rot has already started. Remember, rot is just a bacterial break down of the wood. Once it is wet, it starts. Once the rot starts, it continues.
As far as the cap. I've not seen one that was welded to the hull or the inner skin. You should be able to remove the entire cap as one piece and be able to remove the transom from there.
Can you take a close up pic of the area of concern? You should have an outer skin of the hull with your transom wood and then have a cap over it that should come off. It may be riveted, screwed or have some silicone on it. Some boats even have an inner skin.

 

[markj07]

The area circled in red is the only section of the cap that is welded to the back side of the transom. The rest of the cap appears to have a silicone seal.

 

[huntinfool]

Odd, maybe it had already had a transom put in it and this was how their repair was made. Either way, remove the motor and everything through or into the transom. Grind the weld and remove the cap. Then remove the transom. In the past I have taken a 2x4 and screwed a chain to the end and then put a lag bolt through the chain into the transom and use a 4x4 block as a leverage point and pull an entire transom out whole.

 

[markj07]

I removed two engine well drains to take a closer look at the inside of the transom by the engine. Wood feels moist and I can push an awl through it easily. I think its shot!

 

[markj07]

Today I built an adaptor out of some 2X10 to use on an engine stand. I plan on disconnecting the engine tomorrow and put it on the stand so that I can get started on the transom.

 

[markj07]

I started the engine and let it run for about 10 minutes. I followed that with a compression check. Everything looked good so I started the engine removal. The hardest part was the steering shaft removal. Now I can start with removing the transom cap/ engine well piece.

 

[juggernot]

To me it looks like the original transom was notched out and that motor is hanging way to low now.

 

[markj07]

I am fairly certain that this transom came like this from the factory. Most of the other Spectrum's have the same shape as this one. As far as I can tell this is the original transom top plate and tray. Any others familiar with this spectrum?

Mark

 

[earl60446]

Some manufacturers build those transoms that way so a boat can use a standard length shaft outboard (15 inch), I found a couple other pictures of spectrum 1992 16 ft boats that had identical transoms so almost certainly factory. That being said, I had a wellcraft center console with a transom like that, 15 inch transom and it was a problem, always water sloshing in over the transom. Of course it was a heavy fiberglass boat (emphasis on heavy) and we had a lot of weight in it. A tin boat would handle this a lot better and the problems we had were on the great lakes, big water.
Yet with my experience, I will never buy another boat with a 15 inch transom.
Tim