Alternator does not charge

I have a CAT 3306 diesel, which includes an alternator 130A/12V, Leece-Neville. It seems that the alternator does not do much. It certainly does not charge the house banks, but now my cranking batteries are loosing voltage, as well.
Any suggestions what to look for here? I am not an electrician, but I can use a voltmeter. Photos are available.

http://www.trawlerforum.com/forums/members/15696-albums751.html

I also have a generator, which suppose to charge the cranking batteries, but that does not seem to charge, either.
The batteries are 3 years old and the water level is regularly checked.

You might check alt output w meter. Should be at least hi 13V to lo 14V. If that is suspect remove and have an auto electrical shop check alt out.
Seems suspicious that alt and shore power charger would both fail together.
Are either or both run through diode isolaters to serve 2 or more battys? If so they have a built in V drop and make charging not as complete /efficient.

See link for what I found and fixed on my MShip - Charging System Mods
http://dkloeber.wixsite.com/bacchus/project-pg-4

Bacchus said:

Seems suspicious that alt and shore power charger would both fail together.
Are either or both run through diode isolaters to serve 2 or more battys? If so they have a built in V drop and make charging not as complete /efficient.

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Unfortunately, I don't have much to go on. There is no documentation available. The shore power was upgraded to 50A a while ago, so new wiring was put in place, plus the Inverter/Charger. This setup works fine and the two house banks are charged and maintained.

The cranking batteries are charged separately. I was told to run the generator to charge them. I know, it does not really make sense, since these cranking batteries are starting the engine and the generator. If the Alternator is not charging these, what does?

Perhaps if you look at the pictures, you might see something I don't?

No pics?
Tough to tell anything about wiring w pics and impissible to guess what any PO may have done / modified.
You will likely have to start tracing wires to find out what is connected to what. That's what I had to do as a starting point to know what I had. Then evaluate short comings and possible improvements.
Calder's book on boat electrical systems might be a goid investment.

Bacchus said:

No pics?
Tough to tell anything about wiring w pics and impissible to guess what any PO may have done / modified..

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I have posted photos in my profile. You can see them.

The pictures

I hope they'll show up.

Wire or hire?

What I need to decide, if I wish to troubleshoot this myself and learn, or shall I bite the dust and pay to someone to fix this, or replace the crank batteries charging system?

Now see them. Working from phone could not access albums previously.
Like I said... no way to tell what the circuit connections are from pics.
Only comment I'd make is it looks like more lose unsupported / unprotected cable runs than I would be comfortable with... one seems espevially close to alt pulley.
I know thats not your problem... just a comment.
Really need to develop an as-is schematic.

I would suggest that you hire a marine electrician to look the system over and draw a schematic diagram for you. Get the electrician to explain your system to you so you can get a good understanding of what you have and basically how it works. The money you spend on it will pay off in the long run.

A WAG is that the water damage seen around the front of the engine has infiltrated the alternator.

Agree with #9; hire an ABYC Certified Marine Electrician and have him map out the system, develop a wiring diagram, correct discrepancies found and train you how to do it all.

I do this regularly with my clients...I try really hard to work myself out of a job!

I was told to run the generator to charge them. I know, it does not really make sense, since these cranking batteries are starting the engine and the generator.

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It sounds like there was a known problem, the main engine alternator was not charging the start batteries as it should and the work-around was to use the GenSet to do the job.

If you want to learn, then trace out the wiring yourself. Almost all auto parts stores will test your alternator for free. The cheapest place for a standard alternator is probably ebay. You don't have to have the exact same make/model, but if your tach gets it signal from the alternator, then you need one with that feature. It could be the po was only using the alternator for a tach signal.

The internet is full of info on how alternators work and how to test/rebuild. Also Youtube.

Comodave said:

I would suggest that you hire a marine electrician to look the system over and draw a schematic diagram for you. Get the electrician to explain your system to you so you can get a good understanding of what you have and basically how it works. The money you spend on it will pay off in the long run.

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Yes, I tend to agree with you. It is just a slippery road for a novice to discover this jungle.
I am searching for an electrician now.
Anyone recommends one in the PNW ?

Lepke said:

It could be the po was only using the alternator for a tach signal.

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Interestingly, the voltage test showed 12.45V at the cranking batteries contacts. But the pilothouse volt meter was close to the red already.

ktdtx said:

It sounds like there was a known problem, the main engine alternator was not charging the start batteries as it should and the work-around was to use the GenSet to do the job.

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Yes, this is what I was told by the seller. However, yesterday I ran the generator and it did not charge the crank batteries. At least, I did not see any sign of it on the gauges.

CharlieJ said:

A WAG is that the water damage seen around the front of the engine has infiltrated the alternator.

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That is very much possible. There was water under the engine for long time. The rust proves it. I cannot tell, how high the water came up, but you are making a very good point.
Either way, I will get a new alternator and maybe fix this damaged one for backup.

Why don't you live closer to PNW? LOL

To start to find out if alter. is or is not working

In photo #4. Big red wire on large stud on alter. back. Check for voltage there while NOT running. If voltage shows then the alt. is connected to a battery, just don't,t know which one. Note voltage.

Start engine, raise revs to approx. 1,000 and do the same test. Voltage should rise to appro. 13.5 v or so.

If it does alt. Is Working. Stop engine and start tracing that output wire to find out exactly where it is connected. Need to know..

If voltage does not rise then alter. Is NOT working. Take to a shop for repair or replacement. If replace then get same Leece Neville unit. They are good builders. Don,t compound your trouble with a different unit.

Just a start.

Faster of course would be a Marine electrician.

C lectric said:

To start to find out if alter. is or is not working
In photo #4. Big red wire on large stud on alter. back. Check for voltage there while NOT running. If voltage shows then the alt. is connected to a battery, just don't,t know which one. Note voltage.
Faster of course would be a Marine electrician.

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At the back of the Alt. there are two red wires connected. One comes to the starter battery + connector, the other one goes up to a switch, which can isolate the house banks from the Alt. See photo.

big red wire

From the Alt, it goes up and through the switches and fuses goes to the Inverter.

Get engine running at say 1000rpm and put a voltmeter right on the alternator output (big red) terminal. Report what you find. Do this with AC powered charger off.

Alternators such as yours are very fixable and very well made. All towns medium size up will have a starter/alternator shop that can go through it if needed, typical repair bill is like $100.

I do not replace alts unless burned up, sunk, or bearing failure.

Is there enough water in the batteries?

Check the output of the alt, read across all the fuses in line.
If all is well, call a marine electrician.

In your post you stated that you know how to use a voltmeter. Therefore follow the advice from Bacchus, C letric and SKi , test the output of the alternator with the voltmeter.

OldDan1943 said:

Check the output of the alt, read across all the fuses in line.
If all is well, call a marine electrician.

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I did. An electrician is coming out tomorrow. I'll report back.

Stop depending upon your photos. TO use at this end [ us] they are of little use without labels, and YOUR knowledge of what leads to where.
Not trying to be difficult but they really are not of much use since it where the actual wires run from and to that is important, not your equipment, at this point.

Do the testing asked.

C lectric said:

Stop depending upon your photos.
Do the testing asked.

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I will.
I am not on the boat everyday.
I'll be there tomorrow evening and I'll do what you said. Or, the electrician, who is coming out tomorrow, too.

Sorry, understood.

C lectric said:

Sorry, understood.

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The electrician was over last night. The alternator is dead. Needs repair, or replacement.
The Volt meter in the PH is faulty, needs replacement.
The batteries are fine, so they being charged.
I will get a new alternator and fix the damaged one for backup.

System charts for each of your systems is a great way to learn your boat. Checklists for each time you bump the dock, anchor, fuel, etc, are also great.

Documentation for each of your components should be easy to find online. Run some searches.

Leece-Neville was used on Ford products and you could probably get help on a Ford truck forum or Crown Vic forum. Ambulances and police cars had some powerful alternators.

I think there is a test port on the back of the alternator. You either ground it or put battery voltage to it to make the alternator kick out full potential power.

Good alternator shops are hard to find but worth the effort. Your starter can use a check-up and cleaning from time to time also.

Battery cable connections are always first suspects and most overlooked. I put dielectric grease anywhere oxidation may be an issue. Maybe controversial.

Glad you got it sorted.