zinc anode replacement

[71whaler]

I have a 1983 Evinrude 75HP outboard. Today I went to replace the zinc anode which is located in the lower unit near the anti captivation plate. It is held in by one bolt which goes through the lower unit then through the anode into the lower unit. When I went to remove the bolt, it broke aproximately 3/4 of the way through the anode. Because of this the remaining bolt is still in the lower unit and the anode cannot be removed. Any ideas? Will I have to remove the lower unit? <br /><br />The anode is loose but still in place, is it a bad idea to run it like this? This is the last week of striper season and I wanted to go out tomorrow and Friday.

 

[umblecumbuz]

Re: zinc anode replacement

Hi whaler,<br /><br />As a temporary measure, wedge your anode with a scrap piece of metal - preferably aluminum, so that it makes tight contact with your leg. that'll keep you fishing for a day or two.<br /><br />Longer term - scrap the anode by chiselling it off if necessary, and then try for the broken bolt. There's no harm done by drilling the anti-cavitation plate and fitting a new anode in another position (on top of the plate, not underneath) if you have to. As long as it's in good, clean contact with the metal of the leg you'll be OK.<br /><br />Ciao

 

[gss036]

Re: zinc anode replacement

Just my thoughts, not familiar with your engine. Can you remove the upper piece of the bolt? You are going to have to remove it to put on a new zinc anyway. I would think that it is just corrision/salt build-up around the bolt holding the zinc and you should be able to work if down through the hole. Most of the motors in that area are exposed to salt water, thus you get build up.

 

[jim dozier]

Re: zinc anode replacement

The exact same thing happened to me last night. I drilled the old zinc out by drilling through the bolt from the side at the bottom of the zinc. It won't hurt to go out one more time with it like this but you should drill it out and fix it as soon as possible.

 

[71whaler]

Re: zinc anode replacement

I won't be able to get to the bolt from the top as it is directly into the lower unit, perhaps if I drop the lower unit. I'll probably try as Jimd suggested and remove the zinc by drilling it out and then try and remove the remaining bolt. Thanks for your suggestions.

 

[71whaler]

Re: zinc anode replacement

Update on the damn broken bolt. I tried removing the bolt by using a screw extractor and the screw extractor broke. The guy at the local marine store suggested that I drill a hole through the fin (?) (Skag?) below the prop and use these pancake looking zincs that attach by an allen bolt. Any thoughts on this?

 

[gern1980]

Re: zinc anode replacement

just had to do the exact same thing myself on a 175. postion of the zinc is the same. the best thing to do is go out and get a 90 deegree attachement for your drill(about $25-30). you will save hours of frustration. next go get the best bit you can get and drill the bolt out.then tap it and put a new bolt in. i had the same problem with screw extractors and finally did the above. it worked great and the zinc is where it is supposed to be.this time i put a little silicone on the bolt before i put it back in. good luck.

 

[71whaler]

Re: zinc anode replacement

Yeah I ened up buying a angled drill myself, worked great. My problem is that part of the screw extractor is now inside the broken bolt but I am going to try and drill it out. How far up does the bolt go or how long of a bolt is it? I want to make sure that I do not drill into the lowerunit.

 

[gern1980]

Re: zinc anode replacement

I don't think you can drill far enough in to do any damage to anything, the bolt was in there an inch and a half or two inches. You will probably have to drill the piece of extractor out some, maybe you will get lucky and it will come out before you have to drill all the way through. You should be fine, just remember to tap it before you put your new bolt in to make sure you have good threads. This job took me about 6 hours to figure out, then it went well. You don't have much further to go.