Rudder Port Bolts Corroded away

[Noah8086]

Hey All,

New to it all. Nice to meet you.

"86 Marine Trader 36SD, Single Lehman 135.

All 4 bolts (that I assume are thru bolts) on my Rudder port/Stuffing box are completely rusted off smooth on the interior of the boat. The plate appears to be, at least somewhat, glassed in.

It is not leaking.

I don't know how long it has been like this. I've had the boat just under a year & have spent that amount of time finding things that my horrible surveyor missed. (Story for another day).

Does anyone know the details of this particular set up? Do I need to haul out & address it immediately?

Thanks

 

[Noah8086]

Pic attempt

Pic Attempt

 

[jungpeter]

Hi Noah8086,

Well, those four missing nuts used to secure the rudder stuffing box to the boat hull. And given the bolt heads are no longer present, there's only friction (and the stubs of the corroded fasteners) holding your stuffing box in place. Should that stuffing box decide to break it's tenuous hold to your hull, you'll likely have a major leak in short order. One that's virtually impossible to repair with the boat in the water.

How likely is that to happen? Unknowable. What is the risk? Very large.

Personally, I'd hustle that boat to a lift ASAP. I would drop the rudder and shaft, and inspect for pitting. I would figure out how to remove the wasted fasteners, ensure the stuffing box was properly bedded, repack the shaft, and replace the bolts with bronze bolts. And yes, they are most likely through-bolts, which can only be accessed on the hard.

Again, your boat, your $$. But it looks pretty wasted to me.

Regards,

Pete

 

[Delta Riverat]

I agree.

Just one little grounding tap, one run over big log and it's bilge pump time big time.

 

[jleonard]

Yes do it now. Not a bad job for a do it yourselfer. I replaced all that stuff on my old Mainship years ago as a preventative measure.

 

[Portage_Bay]

Do it now. The only thing keeping it all together now is friction and good luck. If it fails dockside it will be a flooding event. Can your bilge pumps keep up? If it fails underway you could loose control of the boat in addition to flooding.

 

[lwarden]

Probably a good time to look over the bonding (ground wire) when addressing the bolts to ensure all the metal facing outside the hull is sorted. The lack of good bonding is likely the culprit for the fasteners wasting away.

 

[RT Firefly]

Greetings,
Mr. N. Welcome aboard. As noted: YES. Replace ASAP.

 

[Max1]

I have the same set-up on my MT36. Fortunately my bolts are in better shape.
I agree with others here, you need to repair this ASAP. One bump on the rudder/skeg will push the rudder post up and flooding is inevitable.

Drydock and pull the rudder and drill out the threads and re-tap(or re-secure) and replace bolts.

By the way, When I bought my boat, It had a broken rudder.
It wasn't that difficult to pull the shaft, repair the rudder and re-install it.

 

[Noah8086]

Thank you all. Haul ASAP it is.

 

[sean9c]

I may be wrong, or likely am, but aren't the other end of those rotted bolts in the keel and along with the s/s prop tube are buried in cement and the other crud they filled the keels with?

 

[CharlieO.]

I may be wrong, or likely am, but aren't the other end of those rotted bolts in the keel and along with the s/s prop tube are buried in cement and the other crud they filled the keels with?

The keel on these boats generally ends where the prop shaft exits.

 

[TJM]

I would guess that someone replaced the original nuts with some alloy more "active" on the galvanic series of corrosion. Sometimes people think that stainless steel is the best, NOT in this scenario. Matching the alloy of the bolts and the plate is key to protection. As others have said, check good connections on your green bonding wire.

 

[Mainship Pilot]

Looking forward to hearing the stories about your surveyor, that's quite a miss!