How do you check your transom for dry rot or other problems that would require replacement or repair?????
testing a transom for soundness
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Doc Stressor
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I'm not a professional surveyor, so I don't have a moisture meter. The first thing I do is to look for any structural damage such as dings that go deeper than the gel coat. Then I look for screws in the transom such as transducer mounts. I take out the screws and look to see if any water runs out. Replace the screws using 5200 to keep them waterproof. Finally, I take a ball hammer and tap the outside of the transom fairly firmly about every 4" interval. I listen for any change in the sound. A wet spot in the transom usually goes from a sharp tap to a more of a dull thud. A really bad spot sounds hollow.
You can borrow or rent a moisture meter, but in my experience, it's often hard to interpret the results. The calibration is not absolute, so the best you can do is to look for large differences in moisture content in different regions of the transom.
I will also stand on the anti-ventilation plate of the outboard motors and try to jump up and down looking for any flex in the transom.
You can borrow or rent a moisture meter, but in my experience, it's often hard to interpret the results. The calibration is not absolute, so the best you can do is to look for large differences in moisture content in different regions of the transom.
I will also stand on the anti-ventilation plate of the outboard motors and try to jump up and down looking for any flex in the transom.
Thank you Doc, I will try the hammer test. The boat hasnt been in the water since 2003, Its been in my barn or a heated storage bld. Its 1983 Overnighter with twin 90's. These old engines are pretty heavy and I would like to know the transom is in good shape. Thanks again.
SkunkBoat
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The"stand on the motor and look for flex" is a good thing to do.
Sounds like it is your boat? If so, then you can be a little more intrusive.
Remove a lower motor mount bolt and see what comes out. Get your finger or a screwdriver in there and dig.
If possible, lift the motor(s) off the transom and remove the aluminum cap. Looking in there will tell you more than anything else.
Another trick, from the inside, drill small (shallow!) test holes and check the wood that comes out.
Sounds like it is your boat? If so, then you can be a little more intrusive.
Remove a lower motor mount bolt and see what comes out. Get your finger or a screwdriver in there and dig.
If possible, lift the motor(s) off the transom and remove the aluminum cap. Looking in there will tell you more than anything else.
Another trick, from the inside, drill small (shallow!) test holes and check the wood that comes out.
Fishtales
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I would start at the top and then move down.
- Check the white plastic pieces at the notch of the euro transom. Look for cracks.
- Check the bang plate (aluminum cap that rides over the euro transom laterally and under the motors). Look for excessive corrosion, inspect screws and look for any bumps inside. Boats that are outside in the cold weather may exhibit damage.
- Check the engine mounting screws. Is there caulking around the bolts and do they appear well bedded.
- Look for any dealer or owner mounted items. Often these are the first place water makes it's way into the boat.
- Remove some screws - especially any near the bottom of the transom.
- Inspect inside the hull at the transom area. Look for any signs of water or brown staining.
- Do the motor test. Raise the motors and then use the trim switches to bounce the motors on the transom. You may need to do this on a good transom first to establish a baseline.
- Hammer and moisture meter test. If anything above seems fishy, might be good to get someone that knows what they are doing to help. A few hundred here may save thousands later.
tx
- Check the white plastic pieces at the notch of the euro transom. Look for cracks.
- Check the bang plate (aluminum cap that rides over the euro transom laterally and under the motors). Look for excessive corrosion, inspect screws and look for any bumps inside. Boats that are outside in the cold weather may exhibit damage.
- Check the engine mounting screws. Is there caulking around the bolts and do they appear well bedded.
- Look for any dealer or owner mounted items. Often these are the first place water makes it's way into the boat.
- Remove some screws - especially any near the bottom of the transom.
- Inspect inside the hull at the transom area. Look for any signs of water or brown staining.
- Do the motor test. Raise the motors and then use the trim switches to bounce the motors on the transom. You may need to do this on a good transom first to establish a baseline.
- Hammer and moisture meter test. If anything above seems fishy, might be good to get someone that knows what they are doing to help. A few hundred here may save thousands later.
tx
Unless there are obvious structural issues, there is really no substitute for a moisture test performed correctly by someone who knows what he or she is doing.
You can test for delamination with a leather hammer or perhaps a plastic hammer but delamination is an indication of advanced problems. What you want is to know is if you have a moisture problem before it develops into rot and delamination and if there is high moisture, how extensive it is. Local spots with high moisture are often easily fixed since that condition indicates local water intrusion from something like a screw hole or garboard drain leak.
Trying to flex the transom is not all that effective a test. Some transoms flex somewhat but may not have problems. Often, the transom doesn't flex but can be wet. It's just a question of time.
As I mentioned, a moisture test is only as good as the person who does it.
You can test for delamination with a leather hammer or perhaps a plastic hammer but delamination is an indication of advanced problems. What you want is to know is if you have a moisture problem before it develops into rot and delamination and if there is high moisture, how extensive it is. Local spots with high moisture are often easily fixed since that condition indicates local water intrusion from something like a screw hole or garboard drain leak.
Trying to flex the transom is not all that effective a test. Some transoms flex somewhat but may not have problems. Often, the transom doesn't flex but can be wet. It's just a question of time.
As I mentioned, a moisture test is only as good as the person who does it.
Doc Stressor
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I had to replace the transom on my 1975 overnighter, which is the same hull that you have. The problem was caused by rainwater seeping around the aluminum bang plate, not saltwater intrusion below the water line. But any intrusion will cause problems.
There is good advice in this thread. The wood in those old transoms was not encapsulated. You can almost be certain that you have some rot. Since the boat was out of the water and stored indoors for so long, the moisture might be gone but you may still have rot. My transom was full of mold when we cut it out. My stringers were also beginning to go. They also were not fully encapsulated. As mentioned, look for dark stains seeping out of them.
Getting a professional surveyor (if you can find one who is reliable) is good advice.
There is good advice in this thread. The wood in those old transoms was not encapsulated. You can almost be certain that you have some rot. Since the boat was out of the water and stored indoors for so long, the moisture might be gone but you may still have rot. My transom was full of mold when we cut it out. My stringers were also beginning to go. They also were not fully encapsulated. As mentioned, look for dark stains seeping out of them.
Getting a professional surveyor (if you can find one who is reliable) is good advice.
Doc Stressor said:
I Couldn't agree more. I have also found that it is valuable to see if you can find a surveyor who has extensive experience with the brand of boat you are interested in.
Thanks to all who responded. Great advice and tips. I had one of the motors off when I first started working on getting this old girl back in sea worthy shape but wasnt smart enough to look inside the bolt holes. One of the guys who works for me put the motor back on after we got the steering unstuck and working again. Im pretty sure he didnt seal up the bolts so I need to back it back in the shop where I can put a hoist on the engine and take out the bolts again anyway. I will look inside and see what I find. Also will take off the aluminum top strip and check that out as well. Many good tips from guys who have been there, done that. Thank you all very much. Happy boating guys. I will post a few pics and let you know how my project it progressing.