I have a Yanmar 370 with a ZF transmission. I will be having my running gear checked out (possible vibration issue but that is another story) and the technician mentioned that I should be able to turn the prop shaft just below the transmission by hand. When on the lift, turning the prop by hand took some effort, and I could not budge the prop shaft by hand below the transmission. Any suggestions? Thanks!
How Easy Should it be to Turn Prop Shaft
- Thread starter sammy999
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SteveK
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I can turn my shaft from inside the boat. At first need both hands, once moved one hand can turn it freely.
Mine were like that from when I bought the boat. About 20 years later, when out of the water for other reasons, I had the cutlasses all replaced and the shaft alignment trued. Now I can turn them. I don't think there was any effect on anything by not being able to turn the props by hand.
jleonard
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If your boat is in the water then yes it should turn fairly easily.
If it's on a lift or on the hard or in slings, then all bets are off, cause the hull is no longer in it's working shape.
If it's on a lift or on the hard or in slings, then all bets are off, cause the hull is no longer in it's working shape.
psneeld
Guru
There are several reasons that you can't.
Dry shaft as opposed to in water, smaller diameter and 2 struts, tight packing but still runs cool....
Could be an issue, but not necessarily.
Short, absolute answers from many marina techs (in my experience) need lots of extra info.
Dry shaft as opposed to in water, smaller diameter and 2 struts, tight packing but still runs cool....
Could be an issue, but not necessarily.
Short, absolute answers from many marina techs (in my experience) need lots of extra info.
AlanT
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That is a very good point. I just had my boat out of the water and the engine room door would not latch easily. The stresses of the stands had obviously moved things around to the point that a hatch in the middle of the boat did not latch. The movement was about 2mm. As soon as we were back in the water it closed/latched easily.
This is on a heavily built large strong MY.
~Alan
High Wire
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Agree. Fiberglass boats twist a lot when in slings or on the hard. Check after floating a day or two. Also will be hard when the cutlass bearings are dry.
catalinajack
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Whether in the water or out, my shafts used to be very difficult to turn by hand. Inside it took a two foot lever arm. Outside it the 25-inch prop had to be used. All was good after the cutless bearings were replaced, shafts straightened, and engine aligned, in the water.
rslifkin
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Thinking about it, I've never tried to turn my shafts by hand in the water. On land, I know I can turn them with 1 finger on a prop blade (not all the way out at the tip). Not sure I've ever tried grabbing the shaft to turn one though.
In general, if the cutlass bearings don't have enough play to warrant replacement, alignment checks out, stuffing boxes run cool and there's no concerning vibration while running, I wouldn't worry much about the force required to turn the shafts.
In general, if the cutlass bearings don't have enough play to warrant replacement, alignment checks out, stuffing boxes run cool and there's no concerning vibration while running, I wouldn't worry much about the force required to turn the shafts.
