I just purchased a 1974 CD25 and the knot meter does not work. When the boat was hauled I found the impeller badly covered with crud and two of the four balades are broken. Wher can I find a replacement impeller?
alewifehouse@mainecoast.net
Knot meter impeller
Moderator: Jim Walsh
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Matt Cawthorne
Re: Knot meter impeller...Q: What brand?
Tom
What brand is your knot meter? If it happens to be Datamarine (the same as my '72 cd-36) then you can find them at (508) 563-7151. They are located at 53 Portside Drive, Pocasset, Ma 02559-1900. They will need the model number of your unit. If you have a plug to fit the hole then you can often pull the transducer while the boat is in the water. I paint a thin coat of bottom paint on the impeller each winter, but find that by September crud usually stops the impeller from spinning. It is a simple job to pull the transducer and plug the hole. You can use a guest's toothbrush to clean the crud off and then put it back. If your boat is out of the water then take a few minutes to practice the drill.
good luck,
Matt
mcawthor@bellatlantic.net
What brand is your knot meter? If it happens to be Datamarine (the same as my '72 cd-36) then you can find them at (508) 563-7151. They are located at 53 Portside Drive, Pocasset, Ma 02559-1900. They will need the model number of your unit. If you have a plug to fit the hole then you can often pull the transducer while the boat is in the water. I paint a thin coat of bottom paint on the impeller each winter, but find that by September crud usually stops the impeller from spinning. It is a simple job to pull the transducer and plug the hole. You can use a guest's toothbrush to clean the crud off and then put it back. If your boat is out of the water then take a few minutes to practice the drill.
good luck,
Matt
Tom Foley wrote: I just purchased a 1974 CD25 and the knot meter does not work. When the boat was hauled I found the impeller badly covered with crud and two of the four balades are broken. Wher can I find a replacement impeller?
mcawthor@bellatlantic.net
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john churchill
Re: Knot meter impeller
if its a standard SL-1, they don't make a replacement any more. there is another that will work but it takes a different thru hull and the brain needs to be messed with. it costs $80. right now i just kind of guess how fast i'm goingTom Foley wrote: I just purchased a 1974 CD25 and the knot meter does not work. When the boat was hauled I found the impeller badly covered with crud and two of the four balades are broken. Wher can I find a replacement impeller?
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John Nuttall
Re: Knot meter impeller...Q: What brand?
wow! dumb question : how do you pull it and get the plug in ? how much water comes aboard?
nuttallj@msn.com
Matt Cawthorne wrote: Tom
What brand is your knot meter? If it happens to be Datamarine (the same as my '72 cd-36) then you can find them at (508) 563-7151. They are located at 53 Portside Drive, Pocasset, Ma 02559-1900. They will need the model number of your unit. If you have a plug to fit the hole then you can often pull the transducer while the boat is in the water. I paint a thin coat of bottom paint on the impeller each winter, but find that by September crud usually stops the impeller from spinning. It is a simple job to pull the transducer and plug the hole. You can use a guest's toothbrush to clean the crud off and then put it back. If your boat is out of the water then take a few minutes to practice the drill.
good luck,
Matt
Tom Foley wrote: I just purchased a 1974 CD25 and the knot meter does not work. When the boat was hauled I found the impeller badly covered with crud and two of the four balades are broken. Wher can I find a replacement impeller?
nuttallj@msn.com
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Tom Foley
Re: Knot meter impeller...Q: What brand?
1. My boat is out ofthe waterJohn Nuttall wrote: wow! dumb question : how do you pull it and get the plug in ? how much water comes aboard?
A dumb question? I don't think so.
2. My impeller can not be replaced from inside the boat.
A dumb comment?
Tom
John Nuttall wrote:Matt Cawthorne wrote: Tom
What brand is your knot meter? If it happens to be Datamarine (the same as my '72 cd-36) then you can find them at (508) 563-7151. They are located at 53 Portside Drive, Pocasset, Ma 02559-1900. They will need the model number of your unit. If you have a plug to fit the hole then you can often pull the transducer while the boat is in the water. I paint a thin coat of bottom paint on the impeller each winter, but find that by September crud usually stops the impeller from spinning. It is a simple job to pull the transducer and plug the hole. You can use a guest's toothbrush to clean the crud off and then put it back. If your boat is out of the water then take a few minutes to practice the drill.
good luck,
Matt
Tom Foley wrote: I just purchased a 1974 CD25 and the knot meter does not work. When the boat was hauled I found the impeller badly covered with crud and two of the four balades are
alewifehouse@mainecoast.net
-
Tom Foley
Re: Knot meter impeller...Q: What brand?
1. My boat is out ofthe waterJohn Nuttall wrote: wow! dumb question : how do you pull it and get the plug in ? how much water comes aboard?
A dumb question? I don't think so.
2. My impeller can not be replaced from inside the boat.
A dumb comment?
Tom
John Nuttall wrote:Matt Cawthorne wrote: Tom
What brand is your knot meter? If it happens to be Datamarine (the same as my '72 cd-36) then you can find them at (508) 563-7151. They are located at 53 Portside Drive, Pocasset, Ma 02559-1900. They will need the model number of your unit. If you have a plug to fit the hole then you can often pull the transducer while the boat is in the water. I paint a thin coat of bottom paint on the impeller each winter, but find that by September crud usually stops the impeller from spinning. It is a simple job to pull the transducer and plug the hole. You can use a guest's toothbrush to clean the crud off and then put it back. If your boat is out of the water then take a few minutes to practice the drill.
good luck,
Matt
Tom Foley wrote: I just purchased a 1974 CD25 and the knot meter does not work. When the boat was hauled I found the impeller badly covered with crud and two of the four balades are
alewifehouse@mainecoast.net
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Don Sargeant
Re: Knot meter impeller...Q: What brand?
The paddle-type impellers usually come with a plug unit. You simply exchange the plug unit for the impeller unit when you want to clean the shrimp off -- pop one out and pop the other in. The amount of water that comes in is a function of how fast you can act. A quart or two should be the most you'd see. The previous owners of my CD25D had the good grace to pass the plug along with the boat.
don@cliggott.com
Tom Foley wrote:1. My boat is out ofthe waterJohn Nuttall wrote: wow! dumb question : how do you pull it and get the plug in ? how much water comes aboard?
A dumb question? I don't think so.
2. My impeller can not be replaced from inside the boat.
A dumb comment?
Tom
John Nuttall wrote:Matt Cawthorne wrote: Tom
What brand is your knot meter? If it happens to be Datamarine (the same as my '72 cd-36) then you can find them at (508) 563-7151. They are located at 53 Portside Drive, Pocasset, Ma 02559-1900. They will need the model number of your unit. If you have a plug to fit the hole then you can often pull the transducer while the boat is in the water. I paint a thin coat of bottom paint on the impeller each winter, but find that by September crud usually stops the impeller from spinning. It is a simple job to pull the transducer and plug the hole. You can use a guest's toothbrush to clean the crud off and then put it back. If your boat is out of the water then take a few minutes to practice the drill.
good luck,
Matt
don@cliggott.com
-
Don Sargeant
Re: Knot meter impeller...Q: What brand?
The paddle-type impellers usually come with a plug unit. You simply exchange the plug unit for the impeller unit when you want to clean the shrimp off -- pop one out and pop the other in. The amount of water that comes in is a function of how fast you can act. A quart or two should be the most you'd see. The previous owners of my CD25D had the good grace to pass the plug along with the boat.
don@cliggott.com
Tom Foley wrote:1. My boat is out ofthe waterJohn Nuttall wrote: wow! dumb question : how do you pull it and get the plug in ? how much water comes aboard?
A dumb question? I don't think so.
2. My impeller can not be replaced from inside the boat.
A dumb comment?
Tom
John Nuttall wrote:Matt Cawthorne wrote: Tom
What brand is your knot meter? If it happens to be Datamarine (the same as my '72 cd-36) then you can find them at (508) 563-7151. They are located at 53 Portside Drive, Pocasset, Ma 02559-1900. They will need the model number of your unit. If you have a plug to fit the hole then you can often pull the transducer while the boat is in the water. I paint a thin coat of bottom paint on the impeller each winter, but find that by September crud usually stops the impeller from spinning. It is a simple job to pull the transducer and plug the hole. You can use a guest's toothbrush to clean the crud off and then put it back. If your boat is out of the water then take a few minutes to practice the drill.
good luck,
Matt
don@cliggott.com
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Matt Cawthorne
Re: Knot meter impeller
John,
It is actually one of the smartest questions you could ask. You should want to know how much water comes in through a 2 inch hole in your hull!
I have not seen that many knotmeter installations, but every one that I have ever seen has a housing which is bonded into a hole in the hull. The body of the unit which holds the impeller slides into the housing and is sealed with o-rings. Once the body is inserted into the housing there is some sort of safety device to keep it from getting pushed back into the boat. On one unit there was a plastic screw-cap which locked the body to the housing. My Datamarine unit has a pin which passes through the body and housing to hold them in place and then a circular locking ring that keeps the pin in place. On both units the axle of the paddle-wheel is recessed inside the hull so the only way to replace it is to pull the body out of the housing.
As far as how much water comes in, it depends on how well you can access the unit. I usually count on a couple of gallons, because I have to reach a couple of feet and can only get one arm in at a time. The plug that I have came with the unit so that when I remove the body of the transducer the plug fits exactly and seals perfectly. It took a lot of courage to do it the first time, but it is good to know how to do it. Dead reconing (SP?) requires a knowledge of your speed/distance.
If you can find the manufacturer of your unit, they could probably sell you one of these plugs, or if you are clever and your boat is out of the water you might be able to make one from a piece of pvc pipe and some o-rings.
Good luck.
Matt
mcawthor@bellatlantic.net
It is actually one of the smartest questions you could ask. You should want to know how much water comes in through a 2 inch hole in your hull!
I have not seen that many knotmeter installations, but every one that I have ever seen has a housing which is bonded into a hole in the hull. The body of the unit which holds the impeller slides into the housing and is sealed with o-rings. Once the body is inserted into the housing there is some sort of safety device to keep it from getting pushed back into the boat. On one unit there was a plastic screw-cap which locked the body to the housing. My Datamarine unit has a pin which passes through the body and housing to hold them in place and then a circular locking ring that keeps the pin in place. On both units the axle of the paddle-wheel is recessed inside the hull so the only way to replace it is to pull the body out of the housing.
As far as how much water comes in, it depends on how well you can access the unit. I usually count on a couple of gallons, because I have to reach a couple of feet and can only get one arm in at a time. The plug that I have came with the unit so that when I remove the body of the transducer the plug fits exactly and seals perfectly. It took a lot of courage to do it the first time, but it is good to know how to do it. Dead reconing (SP?) requires a knowledge of your speed/distance.
If you can find the manufacturer of your unit, they could probably sell you one of these plugs, or if you are clever and your boat is out of the water you might be able to make one from a piece of pvc pipe and some o-rings.
Good luck.
Matt
John Nuttall wrote: wow! dumb question : how do you pull it and get the plug in ? how much water comes aboard?
Matt Cawthorne wrote: Tom
What brand is your knot meter? If it happens to be Datamarine (the same as my '72 cd-36) then you can find them at (508) 563-7151. They are located at 53 Portside Drive, Pocasset, Ma 02559-1900. They will need the model number of your unit. If you have a plug to fit the hole then you can often pull the transducer while the boat is in the water. I paint a thin coat of bottom paint on the impeller each winter, but find that by September crud usually stops the impeller from spinning. It is a simple job to pull the transducer and plug the hole. You can use a guest's toothbrush to clean the crud off and then put it back. If your boat is out of the water then take a few minutes to practice the drill.
good luck,
Matt
Tom Foley wrote: I just purchased a 1974 CD25 and the knot meter does not work. When the boat was hauled I found the impeller badly covered with crud and two of the four balades are broken. Wher can I find a replacement impeller?
mcawthor@bellatlantic.net