I just pulled into harbor and was looking over the engine and found a key that looks like it belongs in the key way connecting the shaft to the transmission. I took some photos because it's hard to explain. I sailed for about 4 hours / 30 miles today and didn't motor except to the mooring. It was rough and I suppose it could have jarred loose. Tapping it in it is going tough. Should I leave it halfway and wait for the mechanic when I get home ? Or should I tap it in? The photos shows it reinstalled until I met serious resistance. I assume I won't have as great a sail home in a couple days and will do more motoring. Thanks for advice.
Michael, when the key fell out the shaft may have turned slightly with respect to the coupling. The best solution would be to back off the set screws, realign the shaft slot with the coupling slot and reinsert the key. The key should tap in without a great deal of resistance. Roughly 1/2" of the key should remain exposed when fully seated…depending on your shaft position.
Once inserted tighten the set screws again. Put a hose clamp over the end of the exposed shaft making sure the hose clamp is up against the back of the key so that it can’t slide out again.
Ron
Ron & Diane Schryver
“Alpha Waves” '87 NS30U #393
Georgian Bay
Mike: Are you sure you didn't find a key someone had dropped and yours is still in place?? I guess it could come out but it seems strange. If you do decide to take the assembly apart, make sure that there is a dimple in the shaft for the set screw.
Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
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Joe, The key way was empty and I assume there should be a key in it. Too much of a coincidence that one was laying under the engine. I think the only other place that has this type of key is the steering wheel.
I have the key partially back in but don't want to force it. See photo in first post. I put a hose clamp around it and will watch it closely when motoring on my way home. I think I'll leave it to the mechanic to evaluate the situation and play with the set screws, etc. I had a dripless shaft log put in a couple years ago with a new transmission and i think it's wise at this point to have the mechanic put a professional eye on everything. I just don't want to damage anything getting the boat 30 miles home.
Btw I lock the transmission in reverse when sailing like yesterday. So I suppose with the violent motion I experienced yesterday, if the key way was pointed down, the key could have worked out.
I just finished an 11 day cruise last weekend when I covered probably at least 300 miles. I really have no idea how long the key has been out. Could have just happened during yesterday's rough sail when I wasn't using the engine anyway or it could have happened at any point during the season and I just didn't notice.
I'm not sure of the implications. Anyone? This never happened to me before.
Thanks all.
Michael Passero
Born To Run, NS 33, #42
New London, CT USA
Michael,
By looking at your photo’s it appears the key is a little worn down and simply fell out.
What kept everything together was the 2 collar bolts that are tapered at the bottom end. They mate with a pair of deep dimples on your prop shaft. My suggestion is to buy a new 1/4"X1/4" key for replacement, plus purchase a “shaft collar” that’s related to the size of your prop shaft. You have plenty of room for this shaft collar, and will ensure to hold the key in place.
The key can be driven in as far as the opposite face of the flange. I believe you can bury a 3" (maybe even 4") key inside the flange.
It’s a good thing that you caught this when you did. Imagine if during your rough sailing adventure, your key slipped away to a place and never seen again. You would have never know if there would be a problem.
Jack Dokter
Nine Lives 099 26C
Penetang, On
Mike, the fact that you were able to partially slip the key back in suggests that the two slots are somewhat aligned but not aligned enough to put the key all the way back in…so the set screw is doing all the work connecting the prop shaft to the transmission. This also means that the set screw is the only thing holding the shaft from sliding aft. If the shaft slides far enough aft…out of the transmission coupling you will lose all power to the prop. If the shaft slides farther past the dripless shaft seal…not only will you have no power you will also have a 1" leak to deal with. If the shaft moves out even farther and comes in contact with the rudder it may jam the rudder.
In short it really needs to be dealt with ASAP. If you intend to risk a trip then make sure that you are at minimum idle when you change gears to minimize stress on the set screw and key assembly. You don’t want anything to slip.
Ron
Thanks Jack and Joe
Thank you all for the advice and help. I'm on a lay day before sailing home tomorrow so I decided to investigated further trying to get the transmission coupling key properly back in the slot. I was being careful not to force it and was meeting resistance.
Here's how I preceded. I took the channel locks and pulled partially installed key fully back out. I had only managed to get it in about 1/2 inch as you may have noticed from my original photo. I cleaned the old dried grease off the key, polished it up and put new grease on it. I slid it back in the slot as far as it would go until it bound up again. I then ran the engine at the lowest possible rpm and shifted gears between forward, neutral and reverse a couple times. I then shut down the engine and wiggled the key and it slip all the way in without resistance. See new photo. I ran the engine and shifted the transmission again and everything seems fine. Note in the photo that I put a hose clamp at the end of the shaft to prevent the key from sliding out again just in case this wasn't just a weird fluky event.
Michael Passero
Born To Run, NS 33, #42
I strongly suggest you check the set screw or screws for tightness, Mike.
Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
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.....and move the hose clamp on the shaft until it contacts the key.