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Messages - 2ndwish

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1
At your dock, try shifting at the transmission itself. If it is still difficult, disconnect the tranny cable and try it again . If it is still problematic, you might have a transmission problem, if not it is a cable or shifter problem. Eliminate the easy stuff before calling in the big guns!  

2
Ok- my last post on this subject...If you read Mainesail's last post carefully, he says that Ron will get 2 years assuming he mooring sails. The data presented from PS support that. Ron does not appear to mooring sail (only he can comment on this). I completely agree that repeated partial recharges without fully charging with a three stage charger in between will reduce the life of his batteries. That is not what he appears to be doing. He says he deep discharges, partially recharges with solar panels and then fully charges (hopefully with a modern three-stage charger) when he returns to the dock. Repeated PSOC for thirty days- not a good idea, a day or two , probably not such a big deal. Hard to call it murder, but that's my opinion. Your boat, your choice.

3
I never meant to suggest there is something wrong with big battery banks. It is just that deeply discharged banks and the high output alternators (and chargers) that charge larger banks, carry large currents.  Currents are what causes the heating at resistive connections. The heat generated in a resistor goes as the square of the current (twice the current, 4 times the heat). The post was intended convey the message that if you have such a system (and many of us do), check your connections regularly because they are more prone to this particular problem. The connections that should be checked are on virtually every heavy duty cable in the system and the alternator output. The alternator output (and the starter lug which is often the other end of it)is particularly prone to loosening because the engine vibrates and gets hot and cold.

4
Footloose- You're right, it would not have prevented the problem, but it would have saved the"perko" switch and the wires around it. When the stud of the alternator contacted the housing, it shorted the batteries. The switch was the weak link in the circuit so it went first- luckily (it acted as a somewhat expensive fuse).

5
This weekend, during a long cruise, a friend of mine radioed that he was having concerns about his engine (Universal M35B) and something didn't smell right. When I arrived he was running his engine and there was a clear burning smell. We removed the engine cover and found sparks flying from the alternator output. He shut down the engine, turned off the "perko" and another friend joined us in the diagnosis.

The battery bank is about 400 AH and I believe the alt was more than 80A with an external Balmar regulator (equipped for alt temp sensing but not installed). What happened was that the alternator output nut had worked loose (diesels are known to vibrate) and the joint had become resistive. That joint, driven by alternator and in part by the external alt regulator, got so hot that it melted nearby wires and the alternator output stud isolating standoff. The stud in turn, able to move, was intermittently shorting to the case. A post mortem revealed that the stud was white with oxidation suggesting it was red hot at some point. Furthermore, since the battery cable system was not fused at the battery (per Mainesail and ABYC recommendations), the short took out the "Perko" switch and melted adjacent wires. It was fortunate that our other friend has an awesome spares kit (and some fantastic wiring and diagnostic skills to boot) and actually had a switch that fit the panel. This was all caused by a wire in a high capacity alternator system that had worked loose. We disconnected the alternator, he got his batteries charged with a generator and he made it safely home without incident.

The cautionary message: check your connections regularly on a high current system and fuse your batteries. Our friend was very fortunate to not have a fire on-board. Hope this information helps the next person.

6
Quote
Taking them to 11.8V loaded, at the typical house loads, is in the range of 70% + DOD.....
Mainesail-So assuming that is correct, how many cycles can Ron expect from his AGM batteries at that DoD?

I'm not disagreeing that Ron is not treating as well as he possibly could, but he is not treating them all that differently than most of us do when cruising- we deep cycle them, then run the alternator or solar array or generator to get them as high as we can, given engine noise or sun limitations, but rarely to ~100% SoC. Because he only uses solar, he discharges them deeper than we do, so his AGM max cycles will be fewer, but it might not even be noticeable in the end.

I am going to post another story from this weekend about the dangers of large battery banks and high capacity alternators...stay tuned.

7
I do realize that discussions of batteries is a bit like religion and don't wish to stir the ire of people with a lot more experience than myself and no I am not the PO in this case, but let's look at the facts here...

1) I suspect from reading Ron's post that he is describing the "loaded" voltage on the battery, from which it is difficult to determine a SOC. If he let the battery rest for an hour, I'd bet the voltage would rise above 11.8V.

2) Most of us use our batteries much the way he does while seasonal cruising. That is, we have undersized alternators and rarely put back full charge when running the engine on a cruise. Some of us carry portable generators ($1000) to better top off our batteries, much to the annoyance of our anchorage neighbors.  I noticed the other day, after a three-day stop, that my batteries (400 AH GC) were approaching 50%. On my cruise home, even after 2 hours of motoring, my 51 A alternator was unable to register 13V at the panel meter. Am I killing my batteries? Well yes and no. Any time you cycle the batteries, you are taking some of their life, but that is what they are for! Would I have been better off not charging them underway and waiting until I returned to shore where I could use my 100A 3 stage charger- I doubt it. Putting some charge back in a depleted battery has got to be better than letting is sit depleted- which is the worst thing you can do for them.

3) I would argue that you have to look at how you use your batteries is a big part of the system you put together. Your batteries start dying the minute they leave the factory. If you treat them very well, avoiding high temperatures, discharges more than 50%, use ideal charging techniques and never leave them discharged, you might get 10-12 years out of them (for AGMs), maybe 8 if they are wet-cells. It is quite typical for most of us to get 6 years out of our wet cells. How many cycles does a typical summer cruiser put on those batteries? 10/year if you are lucky? That's 60 cycles over a typical battery lifetime, 120 for AGMs. Compare that to the chart from page 3 of the data sheet I've attached from Trojan for cycles vs DOD. As you can see at 80% depletion, you get 500 cycles vs 1000 for 50% discharge. Even if I apply mainesail's very useful rule of thumb of degrading this by a factor of 2, Ron's batteries should last 250 cycles, which should provide him many good years of service. If Ron is lucky enough to cruise more than that in a summer, then he should think about investing in hardware to prolong his battery life.

We can spend thousands of dollars on generators, high output alternators, external smart chargers etc, but we will be saving money 5-10 years down the road, assuming the batteries don't fail for some other reason (shorted or open plates) long after the warranty has expired. That said, it is a good idea to make sure you can provide every reasonable source of charge to your house bank (like an undersized alternator) because the one thing that is certain to kill your battery is leaving it discharged for a long period of time. I hate terms like "battery murderer", because we all take life from our batteries as we use them, but that is what they are for. Some do it more quickly than others.
Sorry batteries.

 

8
Stu- Your memory continues to amaze (I have no clue what I had for lunch yesterday). Those posts were spot on and might have even solved a further mystery we had - a sudden and unrepeatable power loss when our tank was half full. I'm going to take a close look at the spade connector on the oil switch.  Two questions remain: Facet makes a positive shut-off version of the same Cube fuel pump- why didn't WB use that one? Given the flakey design of the fuel pump/solenoid/OP buzzer circuit, why don't more owners see buzzer/light issues when starting?

9
Main Message Board / Re: Water Heater Issue
« on: June 24, 2015, 09:53:16 AM »
Clay- On our 380 ('97 model year), we had a lot of crud in the water heater coolant loop lines.  Looked like Dexcool crud. We had to replace the lines anyway (they were cracking). Blew it out and refilled the lines. The water heats faster now- although it always got hot. On the WB, the water heater loop is a bypass on the main coolant loop, so a problem there might not show up on the engine temp. I'm beginning to think that on boats "more than one problem" is the norm for debugging! Glad you found part of your problem.

10
Main Message Board / Re: Fiberglass hard top dodger finish
« on: June 23, 2015, 06:35:41 PM »
[
Quote
Not quite sure what "sacrificing the gelcoat underneath" means? You would need to clean and prep just like any surface you would apply LP to.

I meant you prep the gelcoat once and then protect it with clear LP for a very long time. All future waxing, compounding is only on the clear coat, so the gelcoat will last longer (you are not removing pigment either). Without it, you have to remove some oxidation every time you wax (very little if you are diligent about waxing of course). This is how car coatings work. Like I said- never tried it- but on an oxidized fiberglass dodger top-what  a perfect platform to experiment on.

11
Hmm. This thread just became very interesting to me. We now have a 42B Four on our new-to-us C380. When you mentioned the funky wiring of the fuel pump, glow plug, alternator, alarm, I realized the wiring diagram of the M25XPB and the WB 42B Four are the same. Just checked the WB site and indeed they are.

I was having some interesting problems with the engine electrical - buzzer wasn't working. Replaced the buzzer with the Radio Shack equivalent (one of Ron's earlier suggestions)and it still didn't work. Measured voltages throughout the system and found that with the key on, engine off, the voltage on the -P terminal of the buzzer was ~8V which was not enough to provide the 4V minimum needed to trigger the buzzer. Checked the pressure switch - seemed opened when the engine was off and low resistance (on) when the engine is running. Checked power and ground harness resistances and they were ok. Disconnected the indicator lights from the buzzer and got a reading closer to 0V and the buzzer worked great. It struck me that the design is funky because it looks like the buzzer should be triggered by the current path to ground through the fuel pump when the oil pressure sender switch is off and not providing +12 V to the pump. It looks like they added a 1000 ohm resistor to ground when they switched to the solid state pump which has internal circuitry to run the pump. The problem is that the Seaward panel has the bulb right across the buzzer terminals and with its relatively low resistance (bulb resistance is between 20 and 1000 ohms), drags that -P to a higher voltage.

That made me think that others must be having the same problem. I figured that there was inadequate margin in the design and the original buzzers had enough margin to work, but the replacement didn't. Funny thing is that no one on the 380 site reported problems. I concluded that the Radio Shack buzzer, which has identical specs to the Intervox original, must somehow be different. This was further indicated by the fact that the OP buzzer wouldn't work when I hooked up the OT light (which will hold the -C terminal high unless the engine overheats). I've been happily using the engine with the lights disconnected and all seems  to work. I stand by my conclusion that the design margin is poor and the original buzzer is just different enough to work. I will  test it by buying an Intervox buzzer and trying it(just too cheep to spend the 12 bucks right now).

This whole thing pointed to another wiring mystery that someone may be able to shed light on. The fuel pump in the key-on, engine-on position gets power through the oil pressure switch, the idea being that the oil pressure drops and the engine will auto stop when the voltage cuts out- seems like a good idea. So I tried it- disconnected the fuel pump power wire while running assuming the engine would cut out. After 15 minutes of running under load I got tired of waiting for it to stop and ended the experiment. I thought the Facet Cube pump WB uses has a positive shut off. Apparently it does not. The fuel tank on the 380 is high enough that once running, it will keep going, even without a pump and only half a tank of fuel- which begs the question. Why is it wired that way in the first place?

Given the similarity in wiring, I'd be curious to know if C34 owners with M25XPBs have seen anything like this. Sorry for the long post. Even the local WB rep was mystified.     


12
Main Message Board / Re: Fiberglass hard top dodger finish
« on: June 23, 2015, 04:34:07 PM »
I've often wondered whether a clear 2-part LP would provide a durable finish without sacrificing the gel-coat underneath. I've been too chicken to try it.

13
Main Message Board / Re: The dreaded fuel leak
« on: June 08, 2015, 03:35:09 PM »
Quote
Sorry about the fuel tank, but take solace in the fact that you probably have the cleanest, skinniest looking engine in the fleet!! How did you do that?!
The 1987s has an M25 XP, that thar is a repower. Still the shiniest engine I've ever seen. Not sure about skinny.

And I'd also suggest a local fabricator, but if you do, make sure they pressure test it. My former boat partner found out the hard way.

14
Main Message Board / Re: Tightening keel bolts
« on: June 01, 2015, 08:28:53 AM »
Just got back to this- was out sailing yesterday. I like to do MA calculations the way I would for a block and tackle. Fin*Din=Fout*Dout. So for the bolt and conveniently say a 1 ft wrench on the bolt, one full turn with 100 lbs (so the torque is 100 ft-lb) would be 100*2*pi*1 ft=628. The bolt has a pitch of 8 per inch (I think it might actually be 9 but it doesn't matter), so in one full turn Dout=1/8 inch =0.125in=(.125in)/(12in/ft) =0.01 ft
so 628 ft-lb=Fout*.01, divide both sides by .01 and Fout=62800 lb.

A few interesting things here a) the bolt diameter never came in b) it assumes a frictionless twist. You could have put the equation entirely in terms of "bolt diameters" as units (of course the force at the bolt radius is greatly multiplied so 100 ft-lb at 0.44 inches is 2727 lb at the bolt radius). As to the friction, these bolts are dry, so I would assume a worst case scenario of 0.1 or 90% goes into friction and our answer would have been 6280 lb. Anyway you can find calculators on the web that work all this math (adding in pitch angles, tensile strength etc) and you end up with a simple relationship:

T=c*D*F where T is torque(in-lb), c=0.1-0.2 (friction), D is the bolt diameter (in), F is force (lb) [now the pitch is gone!-darn math]

This equation gives the answer 14000 lb.- only about a factor of 2 off of my simple minded approach (hmm maybe I've misplaced a factor of 2-sounds like a diameter/radius thing? might also be in the friction definition- close enough though)

Ok now let's turn to preloading... Preloading is black magic, but I would argue here that the bolt that CY used was not a complete POS- let's say grade 2. That bolt has a dry torque spec of 165 ft-lb with a net clamp force of 11400 lb [hmm somewhere in between the two] - this is at 75% of max, so 110 ft-lb has margin even on a grade 2 bolt (higher grades are much better). So the difference in preloading 600 lb of dead weight on each bolt can easily be compensated by a 10% increase in the torque applied . In reality, most torque wrenches are only good to 20% (or worse) and the friction term is uncertain at 50% level, so I doubt this 10% matters much.


All that said, I'd rather be on the hard when snapping a keel bolt than in the water!  

 

15
Main Message Board / Re: Tightening keel bolts
« on: May 31, 2015, 10:55:28 AM »
Those bolts are monsters. A simple mechanical advantage calculation will show that you are getting a ~700:1 advantage on the 100 ft-lb torque. Even with static friction that means that each bolt will be capable of lifting near 10,000 lb. There are 8 bolts so the load from the weight of the keel is even less on each (~5000 lb/8=~600lb), which is peanuts compared to the force on each bolt from the torque alone.  A single bolt should be able to lift the full weight of the keel (ever use a jack-screw on a car? No problem).  In short I don't think it matters much whether you're in the water or not from a load perspective. The only other issue is whether the distortions placed on the keel stub by the rigging are enough to open the fore and aft ends. BTW this issue was addressed in :
http://c34.org/bbs/index.php?PHPSESSID=7b031e73257c91afd4cf6989f9e800de&topic=8027.msg55816#msg55816

It was also alluded to in Indian Falls' awesome description of rebedding the keelhttp://c34.org/bbs/index.php?PHPSESSID=7b031e73257c91afd4cf6989f9e800de&topic=6842.msg46165#msg46165, where he described "cracking sounds" at 50 ft-lb (ie the force was no longer going into lifting the keel, but rather crushing the glass and bedding) .

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