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Dan-
A couple questios:
Is it self priming or does the water level have to reach the driveshaft?.
There is a 2 to1 reduction in the v-drive so assuming the pump is on the prop shaft end, what is the output at 1,000 RPM (2,000 at the engine)?Quent
Clairebuoyant, #134Thanks, Chuck. Couldn’t figure that out from the picture with rudder removed. That’s much better than I feared. I’m aware of the lateral timber under the quadrant, but as others have noted, the plastic bushing in the hole in the timber doesn’t do much.
I contemplated replacing the plastic bushing with a bronze one, but now think that the possibility of the bronze bearing binding on the rudder shaft outweighs any advantage. Time and money go to next item on the list.
QuentIt looks from the picture like there is no lateral support for the stuffing box other than the four bolts holding it down. Some rudder stuffing boxes, but not this one, extend down into the hull around the rudder shaft.
I think maybe more lateral support at the upper end or the rudder shaft would be helpful, at least more than the plastic bushing provides.
Found a bronze skeg bearing at Hamilon Marine part number BKA-83150R. Installing means removing autopilot tiller and steering quadrant, a winter job.
Quent
Clairebuoyant #132Hi Rich-
Of course, you’re right. A proper application of Ohm’s Law.
However, if the windlass battery is not highly charged, or the windlass is heavily loaded, two things will happen. The voltage at the windlass battery will drop, and as the windlass slows and approaches stalling it’s resistance will drop. Current through the #10 wire will increase, and the wire or combiner will fail before the thermal breaker, at least in theory.
Frankly, if I were going for the windlass battery arrangement, I like Tor’s approach of using #6 wire.
I think there is a lot of merit in keeping things simple as others have suggested. On our boat, we compromised by using a smaller and cheaper windlass. It lifts 60# anchor on 5/16″ chain faster than a 64 year old with a manual windlass and is happy with relatively light power cable.
My only real problem is getting the Manson monster to come back up over the roller. Anyone solved that problem?
QuentHi Tor-
You are up early. I agree on not using the windlass to motor upwind. I was just trying to make the point that sometimes the windlass gets worked hard. Heavier wire would do it. #6 is safe to 120 amps. The distinction here is between what is efficient, ie 10% or less voltage drop, and what is safe, the max current without cooking the combiner or the wire.
QI think there might be a problem with this approach. Consider the situation that you are anchored in a deep anchorage, a bit of wind blowing. The engine is runnng at fast idle, and you are running the windlass a couple minutes between breaks to raise the chain and anchor.
The windlass is drawing close to 150 amps which causes the voltage at the windlass battery to drop to about 11.5 volts. The alternator is maintaining the house bank at close to 14 volts. The combiner sensing the charging voltage, closes the relay to charge the windlass battery.
One principle is always fuse to protect the wire. #10 wire is rated at a maximum current of 60 amps (p. 422, West catalogue) the combiner is rated at 50 amps maximum, and the automotive thermal breakers at 70 amps.
Given the voltage difference, a lot of current is going to flow through the #10 wire. Unless the combiner fails first, the wire will get pretty hot before the thermal breaker opens.
I think that I would install a relay that disables the combiner if the windlass is powered up.
QuentDan-
You don’t say what windlass you plan to use. The power draw of the windlass will probably determine the best approach.
Take a look at the charts on p. 422 of the West Marine catalogue. If you tolerate a 10% voltage drop from your battery bank, which assuming your HD alternator is holding at 13+ volts, is better than the less than 12 volts that the forward battery will provide. The chart shows that 1ga or 0ga will work if your load is about 150 amps. If your battery bank is closer, maybe even lighter wire.
I suggest you use tinned marine UL approved 105 degree C wire. A friend of mine set his V berth on fire because he used welding cable for the windlass. Cheap wire corrodes, heats up and catches fire. Cheap insulation melts.
Be sure that your breaker rating is less than the maximum amp rating of the wire.
Quent
Clairebuoyant, #132Alas, Claire is a bit under the weather, so we will have to pass on tonight. Still plan to go to show tomorrow.
For anyone still town Saturday, EYC’s Boatshow Bash is a great party.
QuentAre you planning to be in the part of Pussers that does not require a boat show admission? Otherwise we’ll be there friday.
Quent
ClairebuoyantHere’s one on Craigslist:
http://annapolis.craigslist.org/boa/1968448908.html
Quent
Clairebuoyant #132Herbc-
A lot depends on how heavy your dingy is. Our davits are similar to the ones you are considering. We can carry a RIB but only after adding some additional support. The problem is that the transom is high and the pushpit to which the davits attach is relatively low and flexible.
Quent
Clairebuoyant #132
