'83 Oday 28' Keelbolt Torque and...

Tally Ho · Jan 15, 2024

Bob_S said:
Hello all and thanks in advance for any help you could give. I am about to tighten the keelbolts on my 28. They're 3/4 inch bolts so, as far as I can tell, bolts of that size should be torqued to 95 ft lbs +/-. Does that sound right to any of you that have undertaken this project? Also, importantly I cant find any information about what material lies between the interior of the bilge and the exterior bottom of the keel stub. I have the original mannuals for the boat and they describe the layup of the bottom being solid glass. I'm hoping it isn't wood between the interior skin and the bottom of the stub but ?? Any information or suggestions you could give based on experience would be greatly appreciated.
Fair winds to all,
Bob S.

I don’t think that 95 ft lbs is enough…see attached thread.

I think that the 3/4” should be torqued to 160#.

But also as pointed out in the thread…specific torque values are not that meaningful in this situation because of the layup may compress.

I don’t really use a torque wrench on my O322. I have a torque wrench on the socket, and a 2’ cheater pipe on that and lean into it as hard as I can…. I can sometimes get a little movement….and consider it good enough.

On my 322, the stub keel solid glass as far as I can tell. Maybe someone with a 28 will chime in.

Greg

keel bolt torque

What do keel bolts torque to on Oday 302? Anyone remember what size sockets are required? Thanks Charles

forums.sailboatowners.com

Davidasailor26 · Jan 15, 2024

Pretty sure O’Day used just glass there. Catalina used wood, and when that rots it leads to the Catalina Smile, but I’ve never read about that kind of problem in any O’Day.

dmax · Jan 16, 2024

Yes, O'Day used all glass in the keel stub (I've seen it). I had trouble determining the tourque setting for my boat (also has 3/4" bolts) - after researching, I settled on 115 ft/lb but I never found a specific O'Day recommendation. Catalina recommends 115 for their mid-30's boats. Some charts will say 160 for 3/4" bolts but I don't feel it is necessary to go that high. Having them all the same is more important.

dlochner · Jan 16, 2024

For reference, Sabre suggests 90# for my 1 ⅛" bolts. Stainless bolts may gall if over torqued, which is a bad thing. Also torque specs for dry and lubricated threads will be different.

jibes138 · Jan 18, 2024

What is more important than the specific torque is the clamping force generated by that amount of torque on that bolt size. I think you’ll find a 3/4 bolt at 95 ft-lbs is an enormous clamping force.
So F= T/k x D
F= lbs force
T= inch pounds
K= friction coefficient (.17 for lubricated steel)
D= bolt diameter
F= (95x12)/0.17 x 0.7
F= 5,029 pounds
This is just 1 bolt. If you have say 6 bolts you have 30,000 pounds of force holding your keel on.
Now your keel is a cantilever beam so say you have 3500 pounds of lead. The CG is maybe 2 feet below the keel joint, the Moment when the boat is heeling 90 degrees will be 3500 x 2 = 7,000 pound feet on the keel joint. Hopefully you won’t heel 90 degrees. At rest with no heel you have 30,000 pounds holding up 3500 pounds, a 8.5 factor. Most safety factors are maybe 2 so this is a very robust design.
now say your 8000 pound boat slams into rocks and stops dead with all the force taken by the keel. This is very bad, do not do this.

jibes138 · Jan 18, 2024

My neighbor many years ago rented his C&C 34 to someone. They smashed it into the rocks near Watch Hill. The keel was still attached but behind the keel there was a fracture through the laminate to the inside. The boat was salvaged but severely damaged.

dlochner · Jan 18, 2024

jibes138 said:
My neighbor many years ago rented his C&C 34 to someone. They smashed it into the rocks near Watch Hill. The keel was still attached but behind the keel there was a fracture through the laminate to the inside. The boat was salvaged but severely damaged.

This is classic hard grounding against a rock. The force is transmitted and leveraged by the keel up into the hull aft of the keel. In a long frustrating story, I once briefly owned a boat that had this kind of grounding.

tgzzzz · Jan 20, 2024

Bob_S said:
Hello all and thanks in advance for any help you could give. I am about to tighten the keelbolts on my 28.
Bob S.

Bob, what am I missing here? 28s don't have keel bolts.

dlochner · Jan 20, 2024

tgzzzz said:
Bob, what am I missing here? 28s don't have keel bolts.

I think Bob upsized his boat to a 38 Beneteau but didn't change his profile. :huh:

Davidasailor26 · Jan 20, 2024

tgzzzz said:
Bob, what am I missing here? 28s don't have keel bolts.

In the mid-80's they did have keel bolts with lead bolt-on fin keels. I think some of the earlier models might have been encapsulated instead.

tgzzzz · Jan 20, 2024

Davidasailor26 said:
In the mid-80's they did have keel bolts with lead bolt-on fin keels. I think some of the earlier models might have been encapsulated instead.

I think you are mistaken about the 28s, Cap. No biggie for me.I don't have them. That was a selling point, along with keel stepped stick.

Davidasailor26 · Jan 20, 2024

tgzzzz said:
I think you are mistaken about the 28s, Cap. No biggie for me.I don't have them. That was a selling point, along with keel stepped stick.

My family had an 85 28 for over 25 years. It had bolts. My parents were the original owner so it wasn’t some previous owner funny business.

According to the post at Encapsulated or Keel bolt 1985 O'Day 28 claiming to have spoken to Rudy at D&R Marine about it keels before 83 were encapsulated, 83 was bolt on iron, and 84-85 were bolt on lead.

tgzzzz · Jan 20, 2024

Glad I didn't bet on it.

Davidasailor26 · Jan 20, 2024

tgzzzz said:
Glad I didn't bet on it.

I thought the same thing when I learned there were ones without bolts. I assumed given the similarities between model years in most other ways that they wouldn’t have changed something as seemingly substantial as the keel/hull attachment method.