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Schooner Captain
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Discussion Starter · #1 ·
On the way down the coast we ate our 1" dock line into the prop at 2100RPM...

Its now hard to turn by hand.
I was diving on it the other day and the resistance is equal for the entire revolution. so bent is out of the list of why it is hard to turn (thou it may still be bent)
When the diver untangled the prop he took a sledge to the prop strut. He said it was bent out of shape. I can take the shaft out in the water, thats no problem, but what do i look for to replace?
Did i bend the prop strut, and now i need a new one? where do i even buy one of those?
or is it something else?
I could take photos the next time i splash...
what should i look for under water?
 

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How did the diver know the strut was bent. I have seen plenty that are offset slightly to one side or the other to enable removing the shaft and clearing the rudder. Maybe he bent the strut into what he thought was proper but really knocking it out of alignment.

Even if it was truly bent, a sledgehammer, especially underwater, is not going to get it back to where it originally was. You will need to haul the boat, remove the shaft and check the alignment of the strut.

Before you go diving, remove the bolts at the prop shaft flange and back the shaft out 1/2" and see if it continues to line up with the output flange.
 

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"Its now hard to turn by hand. "
Maybe...thinking aloud and this could all be totally wrong...the cutless bearing is now "too tight" because some debris, some pieces of the line, got stuffed into it? That would have the same effect as over-tightening the shaft log, clamping down on the shaft and making it uniformly harder to turn.
It might be worthwhile to pull the bearing & replace it, in order to eliminate any question of that, if everything else seems right. I'd wonder if the diver whacked the support ON the area of the cutless bearing, compressing it out of round so it now pinches the shaft all the time. No way to tell that unless you ran a dial caliper (etc) inside it after removing the cutless bearing.
 

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Turning the prop in neutral, and you are still turning a gear or two inside the tranny. There will be resistance. You also have a reduction gear that may turn in neutral as well, on that size of a boat. So I say try the boat, and notice any changes in RPM or vibration.
Hitting the prop support may start a leak, just above it.
 

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Schooner Captain
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Discussion Starter · #7 ·
hmmmm....

I didn't question the diver. he had been diving as long as i have been living.
He said it was out, and he hit it and made it better.


On the resistance part, its a hydraulic transmission. So yes, i guess it is still turning something in there, but not much. Also since the rope incident it does not freewheel while sailing.

I will check the bearing again, this time for debris.
 

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soooo the diver took a sledge hammer to unbend the strut with shaft attached...he must be the hulk, Im assuming he used it in a prying manner...but that is one of the dumbest things ive heard lately while shaft is still attached...

man what a help

he made the issue worse...so depending on hull exit like above and strength of shaftlog etc...at the least you have to take strut off bend back into shape...realign shaft strut and mounts...

while shaft is off take it to be balanced if needed same with prop

no easy way out of this without a haulout
 

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Schooner Captain
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Discussion Starter · #10 ·
soooo the diver took a sledge hammer to unbend the strut with shaft attached...he must be the hulk, Im assuming he used it in a prying manner...but that is one of the dumbest things ive heard lately while shaft is still attached...
i heard him banging very hard...

no easy way out of this without a haulout
thats what i was afraid of. need to make a trip to the saint johns river next year i guess.
 

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i heard him banging very hard...

thats what i was afraid of. need to make a trip to the saint johns river next year i guess.
So you will wait until next year to address this? I hope you do not plan on motoring between now and then. If your strut is out and you continue to run the engine, you will potentially be adding to the damage.

What was the point of the video. Did I miss something?
 

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Schooner Captain
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Discussion Starter · #12 ·
So you will wait until next year to address this? I hope you do not plan on motoring between now and then. If your strut is out and you continue to run the engine, you will potentially be adding to the damage.

What was the point of the video. Did I miss something?
nah, we are just dock lovers for a year.

and we ran it for 100 hours like it is.
 

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The video is excellent, and the sound as well. I didn't hear any steel to bronze hammering. Some mechanics lie, to make themselves seem more important. He straightened the strut. Sure he did!
He didn't spend a long time. You may have not have any damage, but some damage is not good.
Motor very short distances, lowest RPM, to your haul out, but nothing long distance.
 

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Bent struts are quite common after rope round the prop, but as others have said, straightening with a hammer! bad idea. If the strut bearing is out of alignment you will get equal resistance as you turn shaft. People spend hours aligning the coupling to 2-3Thou and then forget about the alignment of the strut bearing. When you are out get a clearance fit bearing that will slide and turn in strut, chock the (straight) shaft central and you should be able to slide the new bearing up the shaft and spin it in the strut by hand, this is how we confirm strut bearing carrier alignment.
 

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Discussion Starter · #15 ·
When you are out get a clearance fit bearing that will slide and turn in strut, chock the (straight) shaft central and you should be able to slide the new bearing up the shaft and spin it in the strut by hand, this is how we confirm strut bearing carrier alignment.
I have no idea what that means.
 

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My .02....... were just what Hellosailor posted.......there could be bits of rope debris wedge into the bearing and/or if the strut was hit on the bottom side it could be out of round.....just my .02

Peter
 

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Wandering Aimlessly
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I wrapped my dinghy towline around my prop. It bent the strut, which required taking it off and slowly and gently bringing it back to true. It did not though, affect the rotation of my prop, it only created a vibration and cavitation above a certain RPM.
 
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