Nice boat, but has an extra rust keel, how big of a risk?

Sep 18, 2022
102
Macgregor 25 Cincinnati
Found an 84 Mac 25 boat that I want to be mine, and I would have given asking price tonight if not for the keel.
It was a former saltwater boat, only been in Ohio a couple of years. The keel is so rusty that some flakes are forming in the base metal. It definitely needs to come out, and I'm looking for guidance on how big/bad that is. I couldn't get photos, unfortunately. There are flakes coming off the surface, all over.
Is there a high risk of the bolts shearing off?
Have any of you paid a shop to pull a keel? Is it super expensive?
Will the Ospho that I used on my motorcycle gas tank work on this keel?

I can figure out how to do it myself, I'm confident with the weight and have a stock of 6x6 timber... but if I snap a bolt I won't forgive myself.

It is a rare specimen, glossy gelcoat, very clean inside, owned by a guy who took care of it. Everything else around here is filthy and drilled full of holes for gadgets that aren't on the boat anymore. I want this boat, but I don't want to lose $2k right out of the gate.
 
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Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
Photos? Only the stub keel is rusty on the outside? Keel bolts are OK? If so, get a boatyard quote to sand it down and apply new epoxy barrrier coat (5-7 coats) and 2 coats of antifouling paint then request a repair allowance from the seller against the selling price or a price reduction. Did that with my Hunter 46 when I purchased it.......not a big deal and keel was not pulled. But you really need boat contractor(s) to inspect it and advise on the repair strategy.
 
Sep 18, 2022
102
Macgregor 25 Cincinnati
Photos? Only the stub keel is rusty on the outside? Keel bolts are OK?
The whole keel is rusty, chunks coming off the surface. The bolts, if stainless, are probably ok... but, the holes they pass through in the iron may be opened up and loose and nasty.

Opening them up, reaming, and pressing in a bushing isn't a huge deal for me once it's out. Jusr wanna know if I should budget for that in my offer.
 
Jan 19, 2010
12,377
Hobie 16 & Rhodes 22 Skeeter Charleston
I’ve done this three times… once with a Mac 21… and a Mac 22 and a balboa 26

with the right tools….
Several people here who can give tips

Here are some before and after pics



 
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Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
You should budget for those repairs in your offer unless the boat is being sold as is and disclosed by the seller. As a minimum, budget for the repairs and make them as soon as possible after purchase.
 
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Sep 18, 2022
102
Macgregor 25 Cincinnati
You should budget for those repairs in your offer.
Yup, I'm calling to haggle tonight. What I'm wondering is how much $ those are worth.

After sleeping on it, my only fear in doing it myself is snapping hardware. I have a little PTSD from rusty cars.

I presume all of this hardware is stainless? Do I need to worry about frozen threads and un-sound bolts?
 
Jan 19, 2010
12,377
Hobie 16 & Rhodes 22 Skeeter Charleston
Are we talking about the rudder or the keel?

can’t steer a boat without the rudder
 

RitSim

.
Jan 29, 2018
412
Beneteau 411 Branford
I did a Pearson 26 keel a few years ago that had some bad rust. The premier solution is sandblasting. I did the work myself with a needle scaler and an air compressor. It wasn't perfect but didn't rust again the 3 years i had the boat in brackish water. I needle scaled completely and then used naval jelly on all to put a phosphate coating in place. Followed by Pettit 4700 - follow mfg recommendations on number of coats and recoat times. Then faired out the divots and bottom painted. I now have a bigger boat with a cast iron keel. I added a teardrop zinc to the keel and that helped the rust issue.
 
Jan 19, 2010
12,377
Hobie 16 & Rhodes 22 Skeeter Charleston
I did a Pearson 26 keel a few years ago that had some bad rust. The premier solution is sandblasting. I did the work myself with a needle scaler and an air compressor. It wasn't perfect but didn't rust again the 3 years i had the boat in brackish water. I needle scaled completely and then used naval jelly on all to put a phosphate coating in place. Followed by Pettit 4700 - follow mfg recommendations on number of coats and recoat times. Then faired out the divots and bottom painted. I now have a bigger boat with a cast iron keel. I added a teardrop zinc to the keel and that helped the rust issue.
Me too... air hammer, then needle chipped and then sandblasted B4 phosphate priming.

Rust has A LOT more volume than does pure iron. So even though you are chipping off a lot of rust, you may find you are not actually losing that much iron. The only place I had any real issues was the trailing edge. I had to build that back up with epoxy but a mig-welded strip of mild steel would have probably been the better choice.
 
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Jan 19, 2010
12,377
Hobie 16 & Rhodes 22 Skeeter Charleston
Here are some more pics of the keel restoration.

5 hours of hammerandairchipper.jpg
Five hours of air hammer and chipper

blasted and rust treated.jpg
Sand Blasted and rust treated

first coat primer.jpg
First coat of primer

keel hang_marked up.jpg
Intermediate stage. Trailing edge fixed. First and second barrier coat applied to body.

Chain Brace.jpg
Barrier Coat complete. Body painted.

In position 1.jpg
Putting it all back together.
 
Jan 19, 2010
12,377
Hobie 16 & Rhodes 22 Skeeter Charleston
Rudder, didn't these have a rudder that retracted into the cockpit via a slot in the hull/deck?
The balboa had a unique way of lifiting the rudder. The rudder post passed through a rudder "stock" that then slipped into a trunk in the cockpit. To rais the rudder, you lifted the entire stock up out of the trunk and then turned it 30 degrees or so... and rested the stock on the cockpit floor. You could lift the rudder all of the way out but resting the stock on the floor was far enough to get the boat on the trailer without dragging your rudder on the pavement.

Rudder1.jpg