Bow Thruster Zinc

[Happy Place]

Need your advice...

Last season, I was unable to remove the nut holding the zinc onto my bow thruster. I left it alone, hoping that the zinc would eventually dissolve, exposing the bolt and I could remove it.

Last fall, I noticed that not all of the zinc was gone and I tried to remove the bolt but the allen head looked stripped and I used a reverse thread tool to try and pull it.

Unfortunately, I believe that in fact, the bolt had dropped out at some point and what I thought was the inside of the stripped bolt was in fact the female opening of the bolt hole which I have now damaged beyond repair without pulling the entire unit out and rethreading.

Without incurring the expense and time of removing the thruster, I'm left with few options. One, I suppose it to go without a zinc...but I'm not sure how much corrosion will occur there if I do that.

Another option might be to install a zinc somewhere in the tunnel but that will cost me some measure of thruster power in an already rather weak bow thruster.....plus....where could I install another zinc?

https://photos.google.com/photo/AF1QipM ... QAlQmX4izG

 

[bob daily]

Mr. Not So Happy, You probably only damaged the first few threads, if so you may be able to Tap out (clean the threads) and still have plenty of threads to hold the thruster Zink in place. Just be sure you are using the correct size tap with correct thread (metric or standard). It is worth a try to save you some time and headaches. Best of luck! Bob

 

[Ralf H]

Hi there Happy,

Essentially, what Bob said... That would be the best approach. You could install a zinc somewhere in the tunnel, like you mentioned, but that would simply introduce another hole that you don't need. Hope this helps.

Cheers,

Ralf

 

[Rebel112r]

Is it possible to fill with JB Weld, let harden and drill and retap?

 

[bob daily]

It would be better to use a Helicoil Thread repair, much stronger and easier than messing with J.B.weld and sold at most hardware stores. Bob

 

[knotflying]

Why over think this. If the first few threads are damaged, get the appropriate size tap and rethread it.

 

[Iflytoo]

We are having a problem attaching the zinc to the thruster on our 2012 R27. BoatZincs says the SM31180A is the appropriate zinc but the fastener seems too short - only a couple of threads make it into the thruster and now I can get the fastener to bit at all. The old zinc isn't too bad so we will keep that one on for now - the fastener is the same length (maybe the zinc is not as thick?). Is there a problem with using a longer fastener than the one provided with the zinc?

 

[Rode Trip]

We are having a problem attaching the zinc to the thruster on our 2012 R27. BoatZincs says the SM31180A is the appropriate zinc but the fastener seems too short - only a couple of threads make it into the thruster and now I can get the fastener to bit at all. The old zinc isn't too bad so we will keep that one on for now - the fastener is the same length (maybe the zinc is not as thick?). Is there a problem with using a longer fastener than the one provided with the zinc?

If this pdf uploads it's the response I got from Imtra. I'm having similar issues with both bow and stern thruster anodes.
Edit: It didn't upload. I'll see if I can message it to you.
Edit again. No, apparently I can't post or send a pdf. If you want to message me your email I can send it to you. It's a one page pdf document.