The time has come for me to drop the keel from my '84 Mac25 in order to (1) clean and paint it, (2) remove and replace the main keel bolt (likely bent), and (3) carefully inspect the truck for damage from what was apparently a significant collision at some point in my boat's past which resulted in a 35 degree bend to the locking bolt, an apparent slight bend to the main bolt, and a couple of apparent cracks in the gelcoat immediately forward of the leading edge of the trunk. Seems that I've read somewhere a technique for safely dropping and replacing the keel, but I cannot locate any threads in the archives. I'm particularly concerned about maintaining adequate side-to-side control of the thing while "free", and forward-aft control when trying to realign it with the bolt holes. Any references or particular advice from experience would be most appreciated. I guess at 675 lbs, in a pinch I could get a few members of the local football team to help me horse it back into place!?!
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Might be Able to Help
I have dropped the keel three times on my MAC 23, once on a MAC 21 and twice on a Gulf Coast 21. They all weighed just a little less than what yours does. You need to get it off of the trailer to do it the way I did. Make sure the boat is high enough for the keel to completely clear of the boat. Lower the aft end just a few inches using the keel winch. Remove the nut from the keel bolt. Put a jack under the forward end and apply just a little pressure so that the keel bolt can be rotated. This may require a wrench since it is bent, but it should be more free than it would be if the full keel weight was on it. Take a magic marker and draw a line on the keel below the keel bolt. This line should be even with the bottom of the boat. Remove the keel bolt. Construct a cradle out of two by fours which the keel can drop into and keep it upright. Lower the keel into the cradle using a combination of the jack and jack stands. Lower the aft end using the winch cable. Put a verticle line on the keel through the keel bolt hole and a mark on the bottom of the boat directly below the keel bolt hole. These marks will be used to align the keel. A floor jack works best for all of this since it can be pushed back and forth align the keel. Installation is pretty much the reverse of the above. I jack the keel back up using the alignment marks and then use a drift or a large screwdriver to move the keel for perfect alignment. Just one word of caution. Do not put your finger in the keel bolt hole with the keel in place.
I have dropped the keel three times on my MAC 23, once on a MAC 21 and twice on a Gulf Coast 21. They all weighed just a little less than what yours does. You need to get it off of the trailer to do it the way I did. Make sure the boat is high enough for the keel to completely clear of the boat. Lower the aft end just a few inches using the keel winch. Remove the nut from the keel bolt. Put a jack under the forward end and apply just a little pressure so that the keel bolt can be rotated. This may require a wrench since it is bent, but it should be more free than it would be if the full keel weight was on it. Take a magic marker and draw a line on the keel below the keel bolt. This line should be even with the bottom of the boat. Remove the keel bolt. Construct a cradle out of two by fours which the keel can drop into and keep it upright. Lower the keel into the cradle using a combination of the jack and jack stands. Lower the aft end using the winch cable. Put a verticle line on the keel through the keel bolt hole and a mark on the bottom of the boat directly below the keel bolt hole. These marks will be used to align the keel. A floor jack works best for all of this since it can be pushed back and forth align the keel. Installation is pretty much the reverse of the above. I jack the keel back up using the alignment marks and then use a drift or a large screwdriver to move the keel for perfect alignment. Just one word of caution. Do not put your finger in the keel bolt hole with the keel in place.
AGREE
DAN'S (THE OTHER) ADVICE WAS SOUND. DID MINE MUCH THE SAME WAY, ONLY I RESTED THE KEEL ON A SMALL DOLLY, THE KIND YOU MOVE FURNITURE AROUND ON. WORKED GREAT, EASY TO MOVE AROUND. MAKE SURE IT'S TIED OFF WELL.
DAN'S (THE OTHER) ADVICE WAS SOUND. DID MINE MUCH THE SAME WAY, ONLY I RESTED THE KEEL ON A SMALL DOLLY, THE KIND YOU MOVE FURNITURE AROUND ON. WORKED GREAT, EASY TO MOVE AROUND. MAKE SURE IT'S TIED OFF WELL.
Tool of choice
Somewhat the same as Dan except that instead of jacks, floorjacks and dollies, my tool of choice is a rented transmission jack. They don't go real high so you may have to lower/raise in two stages unless the boat is pretty low. The cradle Dan mentioned is real important; I found my marina already had one. It was a wood rectangle with two uprights at one end. I lowered the cable end of the keel down between the uprights so it couldn't twist, then lowered the front. It was then handy to drag the whole 'sled' out from under the boat on. Later found when raising it, the cable does a pretty good job of keeping it vertical, but I wouldn't trust it. Marking the keel might help, but you're going to buff it up and paint it anyway, right? Is it glass covered or raw castiron? When reinstalling, I had the keel horizontal on the cable and tranny, and jimmied it around with a screwdriver to align the hole, wasn't that hard if you get inside (yes don't use fingers.) Forget the football team, that thing will squash them flatter than a dried-out jellyfish on a piling.
Somewhat the same as Dan except that instead of jacks, floorjacks and dollies, my tool of choice is a rented transmission jack. They don't go real high so you may have to lower/raise in two stages unless the boat is pretty low. The cradle Dan mentioned is real important; I found my marina already had one. It was a wood rectangle with two uprights at one end. I lowered the cable end of the keel down between the uprights so it couldn't twist, then lowered the front. It was then handy to drag the whole 'sled' out from under the boat on. Later found when raising it, the cable does a pretty good job of keeping it vertical, but I wouldn't trust it. Marking the keel might help, but you're going to buff it up and paint it anyway, right? Is it glass covered or raw castiron? When reinstalling, I had the keel horizontal on the cable and tranny, and jimmied it around with a screwdriver to align the hole, wasn't that hard if you get inside (yes don't use fingers.) Forget the football team, that thing will squash them flatter than a dried-out jellyfish on a piling.
Cast Iron
All very good advice. I still dread the task. Keel is cast iron, so far as I can tell. It was literally covered with lumpy concretious "growths" that I assume were some kind of oddball oxidation. Scraped them all off by hand with a drywall blade. As difficult as it was to remove the locking bolt due to its bend (see photo, original post), I'm rather anxious about the condition of the main bolt, and the ability to quickly and easily find a replacement.
All very good advice. I still dread the task. Keel is cast iron, so far as I can tell. It was literally covered with lumpy concretious "growths" that I assume were some kind of oddball oxidation. Scraped them all off by hand with a drywall blade. As difficult as it was to remove the locking bolt due to its bend (see photo, original post), I'm rather anxious about the condition of the main bolt, and the ability to quickly and easily find a replacement.
Keel Bolt
As far as finding a good keel bolt, they are generally stainless steel. I THINK that they were a 5/8" for the MACs and 3/4" for the Gulf Coast. Any good large hardware store should have them plus washers. For some reason I found that it is harder to find stainless steel locknuts.
As far as finding a good keel bolt, they are generally stainless steel. I THINK that they were a 5/8" for the MACs and 3/4" for the Gulf Coast. Any good large hardware store should have them plus washers. For some reason I found that it is harder to find stainless steel locknuts.
How I did it.
I did pretty much the same as Dan McGuire did on my 82 MacGregor 23. The first order of business is to lift the boat off of the trailer. There have been several ways described by others, but I build a couple of “gallowses” out of 4x4. They have worked well for keel work and bottom refinishing. I then rolled my home made dolly under the keel. I placed an automobile jack right under the keelbolt and lifted just enough to take the pressure off. My bolt then slid out easily. Drop the keel into the dolly by alternately lowering the jack and then cranking down a couple of turns on the winch until the keel rests on the dolly. Don’t ever try to man-handle the thing – you will wind up with something crushed or missing. When I got the keel loose and ready to refinish, I first tried wire brushing the rust off, but gave that up after a couple of hours of blood and sweat. A trip over to the sandblaster solved the problem nicely. Hope this helps, Keith Brglund 82 Mac 23 #1582 "Fullwave"
I did pretty much the same as Dan McGuire did on my 82 MacGregor 23. The first order of business is to lift the boat off of the trailer. There have been several ways described by others, but I build a couple of “gallowses” out of 4x4. They have worked well for keel work and bottom refinishing. I then rolled my home made dolly under the keel. I placed an automobile jack right under the keelbolt and lifted just enough to take the pressure off. My bolt then slid out easily. Drop the keel into the dolly by alternately lowering the jack and then cranking down a couple of turns on the winch until the keel rests on the dolly. Don’t ever try to man-handle the thing – you will wind up with something crushed or missing. When I got the keel loose and ready to refinish, I first tried wire brushing the rust off, but gave that up after a couple of hours of blood and sweat. A trip over to the sandblaster solved the problem nicely. Hope this helps, Keith Brglund 82 Mac 23 #1582 "Fullwave"
Hello Dolly
Nice setup, Keith. Sandblasting is great if its available, if not you will have to use something like Rustlok primer that doesn't require total corrosion removal. West Marine Rustlok is apparently different from Petitt Rustlok and may be better after sandblasting. Remember that a primer should be used as soon after blasting as possible, and the WM stuff will etch the metal. Then I think some people have followed with epoxy paints and the bottom paint. If you have trouble finding the pin, there are some specialty fastener places around Annapolis that can probably help. Ask if you need references. And check the pendant for wear. And yes, dropping the keel is intimidating. But when you get it out, its a relief. And when you clean up the keel and slot, its exciting. And when you put it back together, its a gas.
Nice setup, Keith. Sandblasting is great if its available, if not you will have to use something like Rustlok primer that doesn't require total corrosion removal. West Marine Rustlok is apparently different from Petitt Rustlok and may be better after sandblasting. Remember that a primer should be used as soon after blasting as possible, and the WM stuff will etch the metal. Then I think some people have followed with epoxy paints and the bottom paint. If you have trouble finding the pin, there are some specialty fastener places around Annapolis that can probably help. Ask if you need references. And check the pendant for wear. And yes, dropping the keel is intimidating. But when you get it out, its a relief. And when you clean up the keel and slot, its exciting. And when you put it back together, its a gas.
Keel Bolt
I have bent a number of locking bolts on my Mac 25. They are only 3/8" and made of soft stainless stainless steel. The main keel boat is 5/8" bolt and is very hard to bend. Because of the leverage on the locking bolt it is designed to bend first and it doesn't take that much pressure. I bent mine one time powering through 4 ft waves with the keel not down in the locked position and another time running aground. I have never a problem with the main keel bolt. Always straight. Agree that it is a nasty job to scrap all the rust off the keel. Done it a couple of times now. First time just primed it with metal primer and painted it. It rusted again. Last time sprayed it with a rust inhibitor (Duro extend) before repainting. Still rusted. Think it is just something you have to do every few years.
I have bent a number of locking bolts on my Mac 25. They are only 3/8" and made of soft stainless stainless steel. The main keel boat is 5/8" bolt and is very hard to bend. Because of the leverage on the locking bolt it is designed to bend first and it doesn't take that much pressure. I bent mine one time powering through 4 ft waves with the keel not down in the locked position and another time running aground. I have never a problem with the main keel bolt. Always straight. Agree that it is a nasty job to scrap all the rust off the keel. Done it a couple of times now. First time just primed it with metal primer and painted it. It rusted again. Last time sprayed it with a rust inhibitor (Duro extend) before repainting. Still rusted. Think it is just something you have to do every few years.
Rust never sleeps
When we had our trailer sandblasted, the fellow explained that metal absorbs some moisture, especially a porous metal like castiron. You can prime a blasted (old) surface right away and internal moisture will resume the corrosion process under the primer; thats why ordinary primers never seem to last long. It probably needs a process like the hotvac thing, that applies heat and a vacuum to remove internal moisture. Anyway, a marine primer like Rust-Lock (or whatever goes with the epoxy paint) will be more effective seizing up the surface than any can of hardware primer. That said, I agree that metal keels need continuing maintenance and so its good to get intimate with yours. And please, nobody mention galvanizing or I'll 'archive' you.
When we had our trailer sandblasted, the fellow explained that metal absorbs some moisture, especially a porous metal like castiron. You can prime a blasted (old) surface right away and internal moisture will resume the corrosion process under the primer; thats why ordinary primers never seem to last long. It probably needs a process like the hotvac thing, that applies heat and a vacuum to remove internal moisture. Anyway, a marine primer like Rust-Lock (or whatever goes with the epoxy paint) will be more effective seizing up the surface than any can of hardware primer. That said, I agree that metal keels need continuing maintenance and so its good to get intimate with yours. And please, nobody mention galvanizing or I'll 'archive' you.
Steve's Answer
The straps I used were trucker’s straps straight from Home Depot. They are about 2.5 inches wide and rated for 10,000 Lbs. As the boat only weighs 2,500 Lbs., I’m good to go. One bad thing is that they will ratchet “UP” but not down. I painted the keel using Interlux products with good results. They recommend that you paint the keel within one hour of the sand-blasting. As soon as I got home from the sand-blasters I painted it with a two part 2001/2002 epoxy. After the first coat dried, I fared the now exposed casting pits with an Interlux underwater filler. After sanding that smooth, I applied three more coats of epoxy paint and a couple of coats of antifouling paint. Two years later, the keel still looks good except for a couple of dings on the bottom and leading edge where it has met objects more resistant than itself. I can easily touch-up these areas with the boat still on the trailer. Keith Berglund 82 Mac 23 #1582 “Fullwave”
The straps I used were trucker’s straps straight from Home Depot. They are about 2.5 inches wide and rated for 10,000 Lbs. As the boat only weighs 2,500 Lbs., I’m good to go. One bad thing is that they will ratchet “UP” but not down. I painted the keel using Interlux products with good results. They recommend that you paint the keel within one hour of the sand-blasting. As soon as I got home from the sand-blasters I painted it with a two part 2001/2002 epoxy. After the first coat dried, I fared the now exposed casting pits with an Interlux underwater filler. After sanding that smooth, I applied three more coats of epoxy paint and a couple of coats of antifouling paint. Two years later, the keel still looks good except for a couple of dings on the bottom and leading edge where it has met objects more resistant than itself. I can easily touch-up these areas with the boat still on the trailer. Keith Berglund 82 Mac 23 #1582 “Fullwave”
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