Trouble with Anodes on motor extender

"I have an aluminum motor exte

"I have an aluminum motor extender that is hollow. Water collects in the hollow section, making the boat too heavy in the stern. I've determined that the water is most likely getting in through where the large disk anode mates to the surface. On this extender, there are two disk anodes, one on the inside and one on the outside that are connected by a single through bolt. I've cleaned all surfaces and tried to tighten them down as much as possible, but they still leak. Is there any type of sealant I could use that would not defeat the connectivity necessary for the anodes to work properly, but would seal them so water would not get into the extender? If not, does anyone have a way I can work around this problem?"

I would think you could use so

I would think you could use some marine silicon right at the bolt location.

As long as the anode itself still makes contact with the aluminum on the rest of it's surface it should still do the job it was designed to do.

"The extender I assume ia an o

"The extender I assume ia an outboard bracket. (pod) On mine I have a small piece of aluminum square stock welded onto the bottom of the bracket. I have a zinc welded onto this each season therefor no holes and the welding doesn't hurt the powder coating on the bracket itself. I would have the hole filled and just weld in a similar fashion. You must have an inspection cover on the top of the bracket so that the transom bolts can be accessed. If it is a plastic one, they will leak anytime it goes under. I changed mine to an al aluiminum (commercial grade) one and it only leaks about a litre a season."

"Graham, Rollie - Thanks for t

"Graham, Rollie - Thanks for the feedback. The problem is that the hole in the pod is about 3/4" diameter, but the through bolt is only about 3/16th's. You've both given me an idea. I think I will cut two pieces of aluminum stock the size of the anodes, weld them on the outside (one over the current hole)then drill a hole the proper size for each holding bolt, and seal the mating nut from the inside. Rollie - where in the heck did you find a matching aluminum access plate hatch? Currently, I have to re-caulk mine with silicon every time it is removed."

"WD I bought mine from Trotac

"WD I bought mine from Trotac Marine here in town. (www.trotacmarine.com) They specialize in supplying the commercial fishing boats but carry everything. I think there are both 6 and 10 inch aluminim hatches. The hatches have a seal between the cover and the mounting ring, which I lube once a year with vasoline. The cover has a good latching mechanism and is cross hatched so that if it used on a deck it isn't so slippery."

"Here is a picture of the alum

"Here is a picture of the aluminum inspection hatch cover

"Here is a picture of the anod

"Here is a picture of the anode welded to the bottom of the pod. I weld it to ensure the best possible electrical bond to the pod.anode

"Rollie - that is slick. I thi

"Rollie - that is slick. I think I've tracked down to proper replacement hatch, which looks very similar to the one in your picture. Thanks for that recommendation. As for the welded anode - it looks like you are welding the anode tabs on to two tabs installed directly on pod. Are those tabs bolted on or welded on? What material are the tabs made of - aluminum?"

The square stock tabs are weld

The square stock tabs are welded onto the pod and are aluminum. The zinc tabs are also aluminum. (molded into the zinc) You don't want to use dissimilar metals or electrolisis becomes worse.