Need a New Shaft

[Mike11]

Any suggestions on how I can order a new shaft for my port engine for my 1997 350 Mariner? No idea how the shaft broke but it did. I have no idea what size it was or the prop size (both are gone now). Anyone have a number to Carver or anyone that I can give my hull ID to and they can tell me what I need? Thanks in advance for any help you can provide.

[Viper]

Sorry to see that Mike. A good prop machine shop might have some specs for the model/year based on previous jobs. If they kept good records, they'd be able to machine new shafts. The other option is to remove the shafts and send them in to the shop. I can see the start of the keyway so they should be able to go from that. From there, the tapers are standard per the diameter of the shaft so it's easy to determine what the total length was. Someone here with the same model and power plants might be able to help with the prop size.

By the pics, It looks to me like there was some stainless steel crevice corrosion going on. Except for tiny pinholes, there's usually little evidence on the outside that something is going on as it corrodes from the inside out. Do you have anodes on the shafts? I don't see any in the pics.

[km1125]

You can usually measure the shaft diameter on the inside of the boat, right by the coupling to the transmission. For shaft length, they can measure the stbd side from the strut to get total length. You can look at the other prop for sizing and just get the opposite rotation. Did the boat perform well with the old props? In not, now would be the time to consider going up or down in size if you already have to buy a replacement.

Do you know where/when it happened? might be worth getting a local diver with a metal detector to see if they can find the prop if it's not in too deep of water. Might save quite a few $$ if it can be reconditioned. Also might provide some clues why the shaft broke.

Is there any chance you stuck something on the bottom or submerged in the water? Did you have any vibrations going on before you lost the prop?

[buster53]

Just an FYI, Carver doesn’t exist anymore, so getting records is a no. Worst case scenario…. Haul the boat, pull the other shaft and prop and get them duplicated. Obviously, reverse the prop.

[Mike11]

I had no indications that anything was wrong. I had no problems backing my boat back into my slip the last time I took it out so I am confident it broke off in my slip over the winter. I have a diver coming out later this week to dive the slip in hopes that I can recover the broken shaft and prop. I have only had the boat approx a year and a half so I am betting there was something going on with the shaft long before I bought it. From my research I found that I probably have a shaft that is 1-1/4"x 60" DN DT. I reached out to Croix Gear and Machining and they claim to have made the original. A new one that size with them is approx $550. Hoping diver recovers the shaft/prop in the water. Thanks for all the information.

[bud37]

Just an FYI....before ordering I would accurately measure the shafts, it is easy.....good luck on the recovery. If in fact it is corrosion from electrical issues, I would have a certified marine electrician out to check your boat and your slip for problems, re the bonding and anodes.

[bud37]

Just to add, now this does not apply to the OPs case but does bring up the discussion for having a leak stop kit onboard, some rags, a hammer and wooden dowel plugs of various sizes. These shafts can break anywhere along their length possibly causing the shaft to exit the boat hull leaving a nice hole to sink your boat in a hurry.

If the shaft anodes are placed properly they can help to stop the shafts from dropping out if there is a failure between the coupling and the hull tube.