I have a 312 with k planes and noticed that I have corrosion build up on the K Plane right where the indicator cable pass through.

I will I’ll be changing the mounting plate but wanted to know what would cause this and how bad is it to change. I have read that 5200 should be used to install to the transom, is that correct?

thx

I would say 4200. If you ever have to remove it 5200 is going to cause damage to the surface. I could be wrong but. I would be careful and just use 4200 so you don’t damage the surface of the transom.

4200

Thanks I was thinking the same thing. However Formula is suggesting to use 5200 and this is what this use everyday on the plates.

If you or others have used 4200 with success, I will use 4200.

Other question I have is why does this happen? The zincs are installed and look brand new.

Wasn't sealed up good. You have to apply 4200 around the complete outer edge of plates and around all bolt holes/cable holes. Make sure water does not get thru. Seal all threads, everything!!

Thanks for the reply. I will use 4200.

Has anyone taken on this job with this model boat looks like I can do this job with motors still in .

Any advice?

looks like it is 3 weeks until the tabs will get here, there no water intrusion,

Could I cause any damage if any if I boat until it arrives?

I wouldn't run it until everything is back together and sealed. I'm assuming you mean the mounting plates are still off.

No sorry, everything is still together , but wondering if I can seal the small hole with like 4200 until part comes in.

So long as it seals over, I don't think I'd have an issue with it. Cleaning it up after the fact so it seals with the parts might be more of a hassle.