Waste valve seems rusted onto thru-hull
- Thread starter capejt
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Buck...
I can fully understand how you got it mixed up. There is so damn much to keep track of with boats.
I had one the other day that was pretty bad. Fortunately a guy on another forum caught my mistake for me.
We were talking about filling a hole left by a removed through hull. I was explaining the concept behind the 12:1 laminate repair when I mixed up the words depth and diameter.
A 12:1 taper/bevel repair on a 1.5" diameter thru-hull hole is a HUGE grind pattern but a 12:1 taper on a 1.5" hole 1/2" thick or deep is what I meant to say....
Good thing the guy didn't listen to me or he would have been pissed!
I can fully understand how you got it mixed up. There is so damn much to keep track of with boats.
I had one the other day that was pretty bad. Fortunately a guy on another forum caught my mistake for me.
We were talking about filling a hole left by a removed through hull. I was explaining the concept behind the 12:1 laminate repair when I mixed up the words depth and diameter.
A 12:1 taper/bevel repair on a 1.5" diameter thru-hull hole is a HUGE grind pattern but a 12:1 taper on a 1.5" hole 1/2" thick or deep is what I meant to say....
Good thing the guy didn't listen to me or he would have been pissed!
Save your time and money!
Capejt, there is no need to buy an angle grinder or a grinding attachment for a drill. I went through all that trying to remove a thru-hull when the valve would not come off. Due to access I could not cut through the thru-hull properly or safely. I even tried a dremel with cut off wheels without success. What worked was a 1/8 drill bit and drill, a big old flat head screw driver (a cheap chisel will work also), and a hammer. This is done from the outside - step 1: carefully drill a series of holes all the way around just on the inside of "mushroom" part of the thru-hull. Try to drill them as close to parallel to the hull and slowly so as not to hit the laminate. It's easy to tell when you've punched through. Try to drill the holes as close as possible. Step 2: After all the holes are drilled using the screwdriver (or chisel) and hammer, chisel out the material between the holes. The "mushroom" head will drop to the ground. Step 3: pull out the body of the thu-hull and valve out from the inside of the boat.
Hopefully the explanation of the procedure makes sense. It took less than ten minutes for me to remove the thru-hull this way.
Manny
Capejt, there is no need to buy an angle grinder or a grinding attachment for a drill. I went through all that trying to remove a thru-hull when the valve would not come off. Due to access I could not cut through the thru-hull properly or safely. I even tried a dremel with cut off wheels without success. What worked was a 1/8 drill bit and drill, a big old flat head screw driver (a cheap chisel will work also), and a hammer. This is done from the outside - step 1: carefully drill a series of holes all the way around just on the inside of "mushroom" part of the thru-hull. Try to drill them as close to parallel to the hull and slowly so as not to hit the laminate. It's easy to tell when you've punched through. Try to drill the holes as close as possible. Step 2: After all the holes are drilled using the screwdriver (or chisel) and hammer, chisel out the material between the holes. The "mushroom" head will drop to the ground. Step 3: pull out the body of the thu-hull and valve out from the inside of the boat.
Hopefully the explanation of the procedure makes sense. It took less than ten minutes for me to remove the thru-hull this way.
Manny
I should have been more clear..
In how I grind off a thru-hull. I grind the head of the mushroom flush with the hull on the exterior then simply go in the boat grab the valve and pull the whole unit into the boat.. Be careful grinding so you don't have to fair the hull though.
In how I grind off a thru-hull. I grind the head of the mushroom flush with the hull on the exterior then simply go in the boat grab the valve and pull the whole unit into the boat.. Be careful grinding so you don't have to fair the hull though.
I should have been more clear..
In how I grind off a thru-hull. I grind the head of the mushroom flush with the hull on the exterior then simply go in the boat grab the valve and pull the whole unit into the boat.. Be careful grinding so you don't have to fair the hull though.
Focus on grinding the areas closest, and right around the edges of the hole. Because the the shape of the sealant capture area is deepest closest to the threads this area will, with most thru-hulls, break free well before you hit fiberglass or the gelcoat.
Notice in the photo bellow the convex shape of the mushroom head. This area holds the marine sealant to make a seal between the hull and the thru-hulls "mushroom head". If you grind carefully on the opposite side of where I colored it red you can cut the head off without damaging the fiberglass and needing to use a fairing compound to repair it. If you're not comfortable with a 4" angle grinder perhaps one of the Dremel grinding/cut off tools may work. You only need to grind the area directly around the hole for the head to pop off..
In how I grind off a thru-hull. I grind the head of the mushroom flush with the hull on the exterior then simply go in the boat grab the valve and pull the whole unit into the boat.. Be careful grinding so you don't have to fair the hull though.
Focus on grinding the areas closest, and right around the edges of the hole. Because the the shape of the sealant capture area is deepest closest to the threads this area will, with most thru-hulls, break free well before you hit fiberglass or the gelcoat.
Notice in the photo bellow the convex shape of the mushroom head. This area holds the marine sealant to make a seal between the hull and the thru-hulls "mushroom head". If you grind carefully on the opposite side of where I colored it red you can cut the head off without damaging the fiberglass and needing to use a fairing compound to repair it. If you're not comfortable with a 4" angle grinder perhaps one of the Dremel grinding/cut off tools may work. You only need to grind the area directly around the hole for the head to pop off..
One more pic..
I apologize for my MS Paint skills in advance.
Focus your grinding to the area in red. The thru-hull will usually be cut free well before you need to grind anywhere near the area in green. Hope this makes sense..
I apologize for my MS Paint skills in advance.
Focus your grinding to the area in red. The thru-hull will usually be cut free well before you need to grind anywhere near the area in green. Hope this makes sense..
Of course..
But I get the feeling that his boat has mushroom heads. My Catalina 36 had plastic flush mounts thru-hulls and I still ground them off from the outside using a drill and a conical shaped grinding wheel. I had no room in side for a grinder, hacksaw or sawzall..
But I get the feeling that his boat has mushroom heads. My Catalina 36 had plastic flush mounts thru-hulls and I still ground them off from the outside using a drill and a conical shaped grinding wheel. I had no room in side for a grinder, hacksaw or sawzall..
You had a real knuckle buster on the inside.
Boats and house are of about the same complexity but boat pack it into a very small volume. Changing a toilet in a small powder room is easy compared to working on the head in a 27 foot boat.
Boats and house are of about the same complexity but boat pack it into a very small volume. Changing a toilet in a small powder room is easy compared to working on the head in a 27 foot boat.
giving a shot in the morning
Hi Gang,
I broke down and bought the grinder today (Tuesday)and a couple of cutting wheels. Since I was rained out today, I intend to give it go in the morning. I'll let you know how it goes.
I like the idea of drilling and "chiseling". If my first method doesn't pay off, I'll give that a shot.
Also, It's not a plastic, but a heavy duty Brass (bronze?)through hull, so I think grinding the "head" off might get a little tricky, but I'll definately keep that idea in mind as well.
Hi Gang,
I broke down and bought the grinder today (Tuesday)and a couple of cutting wheels. Since I was rained out today, I intend to give it go in the morning. I'll let you know how it goes.
I like the idea of drilling and "chiseling". If my first method doesn't pay off, I'll give that a shot.
Also, It's not a plastic, but a heavy duty Brass (bronze?)through hull, so I think grinding the "head" off might get a little tricky, but I'll definately keep that idea in mind as well.
Try this it will save the Thru-Hull
Capejt,
Most thru-hulls have two spigots up inside them which are intended to be used to prevent the item rotating when it is tightened or loosened in the boat's hull. You need a special key but this can be easily made from a piece of 1/4" or 3/8" thick scrap steel cut to the required width and long enough to project from the open end on the outside. This fits up inside the thru-hull and one needs means of getting leverage on it from the outside using, say, an adjustable wrench whilst an assistant works another wrench on the inside.
This way the thru-hull can be re-used.
Capejt,
Most thru-hulls have two spigots up inside them which are intended to be used to prevent the item rotating when it is tightened or loosened in the boat's hull. You need a special key but this can be easily made from a piece of 1/4" or 3/8" thick scrap steel cut to the required width and long enough to project from the open end on the outside. This fits up inside the thru-hull and one needs means of getting leverage on it from the outside using, say, an adjustable wrench whilst an assistant works another wrench on the inside.
This way the thru-hull can be re-used.
Got it done!
OH HAPPY DAY!!! The grinder worked out great. There was just enough room to cut off the thru-hull "stem" and carefully cut the nut in half that holds the against the backing plate. From there the thruhull slid right out. The new parts fit right in and went together flawlessly. One litte thing though, the old thruhull had a gasket on it to seal against the hull. The instalation of the new one just uses caulking, but I think that's probably enough.
Now it's on to the engine water intake. That one's going to be a rough one to get at too. Why don't they design these boats with replacing these parts in mind?
Thanks once again for all the great suggestions. I can always count on this site and it's members to help when the going gets rough (and sometimes seemingly impossible)
OH HAPPY DAY!!! The grinder worked out great. There was just enough room to cut off the thru-hull "stem" and carefully cut the nut in half that holds the against the backing plate. From there the thruhull slid right out. The new parts fit right in and went together flawlessly. One litte thing though, the old thruhull had a gasket on it to seal against the hull. The instalation of the new one just uses caulking, but I think that's probably enough.
Now it's on to the engine water intake. That one's going to be a rough one to get at too. Why don't they design these boats with replacing these parts in mind?
Thanks once again for all the great suggestions. I can always count on this site and it's members to help when the going gets rough (and sometimes seemingly impossible)
Sure did
Oh yeah, it cost a bundle, but the security and piece of mind is worth it. I did manage to save a few bucks by dealing with Defender as opposed to WM. Probably saved about $100! As for sealant, I was initially inclined to go with 5200, but thought, what if I (or someone else) has to go through this again? So I opted for Life Caulk (BIG GLOBS of it!) I won't know for sure how good a job I did until the Spring (i.e.: leaks), but it looks very good for now.
Oh yeah, it cost a bundle, but the security and piece of mind is worth it. I did manage to save a few bucks by dealing with Defender as opposed to WM. Probably saved about $100! As for sealant, I was initially inclined to go with 5200, but thought, what if I (or someone else) has to go through this again? So I opted for Life Caulk (BIG GLOBS of it!) I won't know for sure how good a job I did until the Spring (i.e.: leaks), but it looks very good for now.
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