Big twin 40hp shear pin material?

[dingbat]

Why does the pin look like bronze? It appears to be 78,000 PSI shear strength if it is bronze? Or could it just be discolored?

It could be marine bronze. Brass has dissimilar metals issues.

Avg. Bronze shear is 35,000 psi

Could be carbon steel with gold iridite finish

Is the old one magnetic?

Keep in mind that a solid, 1/4” round has a cross section of 0.049 square inches.

 

[matt167]

It's non magnetic

I ordered a couple OEM pins online. I was going to take the boat out this weekend but looks like light rain,

 

[racerone]

Some stainless alloys are magnetic and some are not.

 

[gm280]

The color of the pin doesn't mean much. It all depends what the manufacturer wanted as corrosion preventative coating. Yes, even with stainless steel. Could have been anodized...IDK

 

[dingbat]

The color of the pin doesn't mean much. It all depends what the manufacturer wanted as corrosion preventative coating. Yes, even with stainless steel. Could have been anodized...IDK

Anodize is chemically induced build up of Aluminum oxide on the surface of an aluminum.

No aluminum in the matrix, no aluminum oxide to build

Steel alloys are either painted, plated, hot dipped (Galvalume) or have a conversion coating applied.

 

[matt167]

I wonder if years of submersion in lake water could have changed the color?

 

[dwco5051]

I wonder if years of submersion in lake water could have changed the color?

If it steel it could be zinc/chromate plated. Does it look this color?

https://www.lowes.com/pd/Hillman-3-16-in-dia-x-6-ft-L-Zinc-Plated-Steel-Solid-Round-Rod/3053661?cm_mmc=shp-_-c-_-prd-_-hdw-_-google-_-lia-_-213-_-threadedrodandmetalshapes-_-3053661-_-0&placeholder=null&ds_rl=1286981&gclid=CjwKCAjw87SHBhBiEiwAukSeUdd7PQMCtNllxLbLn1W70fOR-P4hYJk9HyqnE9Inb4k3Nrq8TcKfRxoCJUYQAvD_BwE&gclsrc=aw.ds

 

[matt167]

similar to that yes, but it's the same color all the way through, including where it sheared

 

[dingbat]

I wonder if years of submersion in lake water could have changed the color?

I wonder if years of submersion in lake water could have changed the color?

Submersion in water isn’t going to change the color of Stainless. Long term exposure to heat and “work” will change the color.

Post a picture. Pretty easy to tell if you know what to look for

 

[gm280]

Anodize is chemically induced build up of Aluminum oxide on the surface of an aluminum.

No aluminum in the matrix, no aluminum oxide to build

Steel alloys are either painted, plated, hot dipped (Galvalume) or have a conversion coating applied.

You are absolutely correct. Can't anodize stainless steel. Just another case of typing without thinking... Thanks for keeping me straight.

 

[racerone]

I used to do some anodizing of aluminum and also magnesium.-----Uses electricity in a chemical bath.----Quickly coverts the surface aluminum to an oxide.

 

[matt167]

Well, the brass rod I bought came in, and I held it up to the original, and it's identical.. So that must have been a fisherman fix, and I converted the boat back from a purpose built fishing boat to a faimly watercraft as it was originally... A lot of ' keep it going ' was done to the boat.

 

[matt167]

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This is what I bought, and cut 4 pins out of ( for now ).. For sure it will work in a pinch. I have 2 OEM drive pins coming as well

 

[dingbat]

This is what I bought, and cut 4 pins out of ( for now ).. For sure it will work in a pinch. I have 2 OEM drive pins coming as well

C360 H02 - 32,053 psi

 

[matt167]

C360 H02 - 32,053 psi

Interesting, so a little under 1/2 strength of the correct rod.. At least I know it'll work in a pinch. I only sheared it when I shifted it with the idle bumped up a little... Actually it made me panic as it went 'ting' and then I thought I did the gear case in. But then checked the pin and it was cut in half

 

[dingbat]

Interesting, so a little under 1/2 strength of the correct rod.. At least I know it'll work in a pinch. I only sheared it when I shifted it with the idle bumped up a little... Actually it made me panic as it went 'ting' and then I thought I did the gear case in. But then checked the pin and it was cut in half

guessing metal fatigue from shifting in and out of gear plays in to it as well

 

[matt167]

guessing metal fatigue from shifting in and out of gear plays in to it as well

The holes in the prop are elongated, but it does not rock. It's not in bad shape but is on my list of things to fix as I don't think it's the right pitch. I have the OEM manual for the motor which has a pitch chart and I'll order one that matches best. Since there are only 3-4 choices I think