G
Guest
Guest
hi
Generally how long does an anode last if permanently submerged?
Many thanks all
Mike
Generally how long does an anode last if permanently submerged?
Many thanks all
Mike
charles_reed
Active member
Main anodes about 3 seasons in Atlantic waters and about 15 months in the Med,
shaft anodes about a season.
shaft anodes about a season.
VMALLOWS
New member
There is no 'standard' life .... it all depends on the electrolytic circumstances on your boat and/or other nearby boats, especially in a Marina. Having shore power connected may also be a factor.
A standard pear-shaped anode on my Sadler29 was only half worn after 14 years, at which point I decided it was prudent to replace the fixing studs! (had to grind them off).
A standard pear-shaped anode on my Sadler29 was only half worn after 14 years, at which point I decided it was prudent to replace the fixing studs! (had to grind them off).
Sinbad1
New member
Mike, you can't really ask that as a question. Its totally dependent upon a large number of factors.
The basics. Electrolysis is caused by dissimilar metals being in proximity of each ther AND being immersed in a saline solution. (Salt!) This solution allows the carrying of electrical current from between the dissimilar metals. This current 'dissolves' metals over time.
The most obvious dissimilar metals on your boat will be the bronze prop and the stainless shaft. The simplest solution to prevent electrolysis between them is to attach an anode to the shaft. In its simplest form, the anode 'absorbs' the electrical energy flowing about and slowly errodes.
Now the variables. If you are in a marina with sheet pilings or other underwater exposed metal, more electrical current is being created. Similarly if the water is warm and salty.
The size of your anode and whether it is correctly bonded (wired) is another important factor.
Many people will suck their teeth and advise you that anodes and electrolysis is a black art. It isn't. Its extremely simple. Unfortunately it is often confused with stray current corrosion which is another problem with the same unfortunate results for your underwater metal components. To check your bonding and anode effectiveness you need your boat out of the water and you need a decent multimeter.
Heres what you do. Set multimeter to most sensitive Ohms reading. (Resistance) Touch the red and black probes together. Reading is 0.00. Perfect. This is what you want to achieve throughout your bonded circuit. Touch one probe to anode and one to fixing studs of anode...etc etc...keep one probe on anode and touch other probe to metal parts that should be protected. ie prop, shaft etc. Your reading should always be 0.00. This shows that your anode is electrically connected to all the items that you want protecting.
The basics. Electrolysis is caused by dissimilar metals being in proximity of each ther AND being immersed in a saline solution. (Salt!) This solution allows the carrying of electrical current from between the dissimilar metals. This current 'dissolves' metals over time.
The most obvious dissimilar metals on your boat will be the bronze prop and the stainless shaft. The simplest solution to prevent electrolysis between them is to attach an anode to the shaft. In its simplest form, the anode 'absorbs' the electrical energy flowing about and slowly errodes.
Now the variables. If you are in a marina with sheet pilings or other underwater exposed metal, more electrical current is being created. Similarly if the water is warm and salty.
The size of your anode and whether it is correctly bonded (wired) is another important factor.
Many people will suck their teeth and advise you that anodes and electrolysis is a black art. It isn't. Its extremely simple. Unfortunately it is often confused with stray current corrosion which is another problem with the same unfortunate results for your underwater metal components. To check your bonding and anode effectiveness you need your boat out of the water and you need a decent multimeter.
Heres what you do. Set multimeter to most sensitive Ohms reading. (Resistance) Touch the red and black probes together. Reading is 0.00. Perfect. This is what you want to achieve throughout your bonded circuit. Touch one probe to anode and one to fixing studs of anode...etc etc...keep one probe on anode and touch other probe to metal parts that should be protected. ie prop, shaft etc. Your reading should always be 0.00. This shows that your anode is electrically connected to all the items that you want protecting.
David2452
Active member
Oh!,....... Thought this was going to be an interesting biography.
