transom rot or not ?

ex-exec

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I'v been looking at a 1989 grady gulfstream, during the inspection I was tapping all over the transom with a model makers hammer.At all places above the water line it sounded solid, when I got to the bottom paint, well it kind of thumped. I will say that it was mostly at or near the very bottom between the twin engines. The paint was pretty heavy and may have been lifting. I'd like to believe this anyway the boat is otherwise what I'v been looking for. Comments, please i am a coast guard viet vet who wants to get back on the water.
 

blindmullet

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You really have to use a moisture meter. How did the garboard look? Did it look sunken in? Might be hard to tell with bottom paint. The garboard is usually a good area for water intrusion.
 

DennisG01

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Honestly, your best bet is to going to be to hire a reputable surveyor for the hull and possibly a mechanical, as well. Using a moisture meter without having lot's of experience with it isn't very reliable. All those coats of bottom paint can skew it... so can having it recently removed from the water.

I always say... A moisture meter does not a surveyor make. :) A good surveyor is WELL worth the investment.
 

blindmullet

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Honestly, your best bet is to going to be to hire a reputable surveyor for the hull and possibly a mechanical, as well. Using a moisture meter without having lot's of experience with it isn't very reliable. All those coats of bottom paint can skew it... so can having it recently removed from the water.

I always say... A moisture meter does not a surveyor make. :) A good surveyor is WELL worth the investment.
Surveyors are like home inspectors...good luck ;)
 

Halfhitch

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For a start just remove one of the garboard screws. If the core is wet and rotten, you will see water dripping out in a short time. If so either move on or expect the cost of rehabbing the transom. If it doesn't pass this test there is no need to spend the coin for a survey. If it doesn't drip then consider hiring a pro.
 
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seasick

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You really have to use a moisture meter. How did the garboard look? Did it look sunken in? Might be hard to tell with bottom paint. The garboard is usually a good area for water intrusion.
you cant use a moisture meter on bottom paint. You may be able to get some relative readings from the inside though but if the levels increase right at the level that the paint line is on the outside, the readings are not all that informative. The reason that inside readings may work is that most contactless moisture meters have a fairly limited depth that they van read, often it's about 3/4 of an inch. Some can probe an inch or so. Most Grady transoms at a lot thicker especially near the keel. So if the core is really soaked, the meter may see it. On the other hand, if the core is wet towards the outer skin, the meter may not see that.
 

blindmullet

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you cant use a moisture meter on bottom paint. You may be able to get some relative readings from the inside though but if the levels increase right at the level that the paint line is on the outside, the readings are not all that informative. The reason that inside readings may work is that most contactless moisture meters have a fairly limited depth that they van read, often it's about 3/4 of an inch. Some can probe an inch or so. Most Grady transoms at a lot thicker especially near the keel. So if the core is really soaked, the meter may see it. On the other hand, if the core is wet towards the outer skin, the meter may not see that.

Correct. I wasn't suggesting to use a moisture meter on the bottom paint. A simple visual check of the garboard plug and surrounding area can tell a lot. Removing a screw and checking for sunken in hardware is usually a good sign to move on or pay for a professional.
 

seasick

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personally, I wouldn't allow a potential buyer to remove any screws or other hardware. At best, maybe the bilge plug but in reality, the inside of that garboard drain opening can usually be 'inspected' from inside the bilge.

A survey is your best bet. The entire hull above the water line should be spot checked. Relative moisture readings are more informative than absolute numbers.
If you have a moisture test and it found no moisture I would be more concerned than if it had measured moderate moisture. Remember a completely hollowed out core or any void for that mater will read zero moisture.

A 30 year hull will probably have moisture in multiple spots. Don't overlook the deck especially.
 
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Fishtales

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Lots of good advice here. The problem with moisture meters are they can be tough to use and unless you have a lot of experience with them you can get improper or false readings. They are not simply beep, no beep devices. The next is removal of hardware - not a good thing to start backing out screws - especially below the waterline without permission and properly sealing when done. Seasick is spot on that most folks will not allow or appreciate it. You almost have to go into this that there is likely some issues with a 30+ year old boat.