thru hulls

rasbury

So, have been trying to figure out a leak. Have a previous thread but when i pull up the site, it says answered so I don't know if anyone continues to look at it or not! So, I brought it home and ran it on the muffs to see if I was leaking at a hose- have closed cooling. Coupler was just replaced, I have a foot pick up and a thru hull for cooling. I checked the transom connection and it is clamped. No visible water. So, I looked at the thru hulls on the hull. The two in the from look like they have been replaced at some point, plenty of sealant around them. The two in the back for the Genny and engine cooling are very corroded and no visible sealant. I know the easy answer is replace which I will put on the list. Are they not sealed from both sides, are they likely to leak in this condition?

skennelly

I replaced 2 of mine last fall.  When I loosened the nuts the sealant fell apart like dust.  I had a leak which is what prompted me to replace them.  It's not a tough job.

Mine were on a 270 for toilet and ac

rasbury

@skennelly , was that your leak?

skennelly

@rasbury Yes I could see the water coming in.  I used gold bond powder and could see the trickle of water.  Good tip I learned from another thread on the site.

rasbury

I guess I need to see how they assemble and seal. The outside looks like just a cover and guess does not really seal anything?

skennelly

You might have strainers that cover the actual thru hull to prevent sucking sea weed and stuff.  There's normally screws that secure the strainer to the hull on the outside

The actual thru hull should have a nut on the inside and seal would be something like 3m 4200 or 5200.  I chose 5200.

rasbury

@skennelly from what i see, there us something on either side of the hull which makes sense and yes what I am seeing is the strainer which obviously in itself not the issue. I need to get it back in the water and dust some powder around those fittings and the one for the depth gauge. If is not one of those than would have to assume the bellows. That would blow as I just had the out drive off for another repair!

skennelly

@rasbury - good luck with your investigation...hopefully it's not bellows.

rasbury

I got to thinking...maybe when they did the coupler they did not unhook the line for the thru hull and just lifted the motor enough to get at it and pulled on the hose and the thru hull enough to break the seal and start leaking? It sure seemed to start right after that...I do get water in the bilge from the a/c and I had an awful mess with a waste tank that had a mystery hole in it, almost like it was drilled at the same time....hmmmm , I will get it back in the water and spread some powder around and see what I can see!  

skennelly

@rasbury anything is possible.  I'd definitely check with the powder.