Batteries

Status
Not open for further replies.
C

Chief

First sail of the season yesterday. and thought this was strange. I have been posting about replacing my alternator, however never got the project finished. I have a brand new one just sitting. The original seems to work fine, just wanted more amps and an external voltage regulator. My shore charger is a Xanthrax Trucharge 20. I currently have the standard Cat 30 two battery set-up using (2) Group 27 Trojan AGM's. Headed out yesterday for a quick "shake down" sail. We motored for about 20 minutes, then sailed for about one hour. During the sail I had my GPS, Wind, Speed and Depth running. My usual procedure is to start on both batteries, motor out than switch to a single battery. When it is time to motor in I go back to both to start the engine. Yesterday we were having a toug time with a strong incoming tide, and were getting close to a channel marker. I decided to just reach down and start the engine without switching to both batteries. I have done this many times in the past, and although not as much juice, the motor always turned over. keep in mind I was only using the battery for about an hour. Much to my suprise the engine would not turn over. I had to send my wife down to switch to both batteries. At that point it turned right over. Based on the equipment being used, does this sound strange to anyone else? Before I start hiring mechanics I though I would run it by the group.
 

jviss

.
Feb 5, 2004
7,090
Tartan 3800 20 Westport, MA
Question

Is the charger always on at the dock? How old are the batteries? Is the alternator the original, automotive type with about 35A output?
 

GuyT

.
May 8, 2007
406
Hunter 34 South Amboy, NJ
Chief, some things you can check are...

1. Battery connections. Make sure that all the terminals are cleaned and tight. Wire brush all terminals and use electical grease before re-connecting. 2. Battery cables. Make sure lugs are tight and not corroded. 2. Battery Selector Switch - clean the contacts inside if possible with some steel wool and then coat with electrical grease before re-assembly to prevent corrosion. Marine environments are hard on electrical connections - corrosion can be a big cause of electrical issues. Cleaning and inspecting often are the only fix. As far as the batteries - you can swap them and see if it makes a difference. Make sure that the batteries are fully charged, check each battery by starting the engine. Do this after you clean all connections. You should be able to turn over your engine on a single group 27 battery without any problem. My goal would be to get the system to this point.
 
Sep 25, 2008
7,688
Alden 50 Sarasota, Florida
check batteries

A small diesel should start with no problem on one (good) battery. Regardless of your charging system which sounds adequate, it's likely one or both batteries are questionable and you don't mention if they are showing good resting voltage or if you have checked their sp gravity readings to determine if they are okay. It is a pretty good indication that needing both to start is a battery prtoblem
 
W

Warren Milberg

This certainly sounds

like you've come to the end of the life of one (or both) of your batteries. I suggest disconnecting them from everything and letting them sit unused for at least 24 hrs. Then test their voltage with a VOM. This won't tell you much about available cranking amps, but it will give you sense about how well, or not, your batteries can hold a charge. If one or both don't read at least 12.5 or more volts, it's time to look for battery sales. Another thing you may want to do if you can remove these batteries easily is to take them into a West Marine or other shop and have them load tested. BTW, I do about the same as you re battery usage. Start on "Both" then switch to one after the engine is shut down. Then switch back to "Both" to restart the engine. On occasion,I have just used one battery (and I only use Group 24's as they are light and cheap and I don't have a high demand) and it will start my 16 hp Yanmar easily. I typically get 5-7 yrs out of Group 24 batteries and I'm happy with that.
 
C

Chief

Thanks for all of the responses. Theyare AGM so they are sealed, no checking fluid levels. I will check the connections,as well as load. The alternator is the stock original 55 amp Motorola. Ipurchased a new Leece Neevile, 72 amp, with Balmar External Regulator. I was going to install myself, but ran into some PO mods that I could not figure out. My yard was to install after I splashed, but after 12 days of the boat sitting I just took the boat, and am now looking for a mechanic to do the work.
 
C

Chief

In response to some of the questions asked. The batteries are one season old, I invested in AGM because of the lack of maintenance and long life. One season would hardly be long life. I am in a slip and they are always on charge, and only seem to take about an hour to come up full after a full dsys sail. I do have a temperature sensor wired into the charging circuit, and the charger is set to AGM. I do realize that a standard alternator is not correct to charge AGM's, but I might have put 6 hours max, on alternator charge last year vs shore charger. I doubt this would fry new AGM's? That is the reason my winter project was to replace the alternator and add a voltage regulator. Anyone have a good marine electrician on the South Shore of Long Island. I have all of the materials.
 
Jan 5, 2007
101
- - NY
How is your charger wired in?

When you are on shore power are you actually charging BOTH batteries? Might pay to take some readings at the terminal of each battery when the charger is on and see what you are getting. Sounds like the battery may have been flat to begin with.
 
Status
Not open for further replies.