DSCN3275Recently I purchased a battery tester. I knew that one of the batteries was bad as it would not turn over the engine for starting. I started by testing a couple of Costco 6vdc golf cart batteries that a neighbor had given to me. I tested them under load and they passed. Next I disconnected the 2 Lifeline GPL-4CT batteries and each one tested good. After a couple of days a neighbor boat said their batteries were bad and would have to buy new ones. I went and looked at them and found that the fluid level was just barely over the plates. I had them add distilled water to the proper level and charge them overnight. The next morning I brought the tester to their boat and tested each battery after it had been disconnected. All batteries tested good saving them a lot of money.

Good starting batteryNow I had tested 8 batteries and figured that the cost of the tester had paid for itself. The one thing I didn’t know is what a bad battery test would look like. Well I still hadn’t tested the 2 GPL-4DL batteries. I suspected one of them would be bad. I disconnected the suspect one and put on the tester. It tested good! Now I am not sure that I would know what a bad battery would look like. I disconnected the last GPL-4DL battery and connected the tester. It read good voltage. Now I hit the load button. Immediately it went to the bad zone and continued downward. I had found my bad battery. The bad part is that it is connected to the 2 Lifeline GPL-4CT batteries that had tested good. Fortunate that there is a Blue Sea Systems ACR battery link between the batteries.


Now to remove the battery. This battery weighs 124.00 lbs. (56.20 kgs). I have to remove the good GPL-4DL battery and then slide over the bad battery and then lift that battery out. I found that if I lifted one end of the battery up and placed it on the edge of the battery compartment I could then lift the other end up and using this lever technique I was able to get both batteries out. To put the good battery back in I enlisted the help of my Admiral. We were going to lever the battery back into place but due to circumstances beyond our control we just put it all the way in the battery box.

DSCN3245We had just attended the Pacific Sail Sailboat show in Oakland and purchased an additional 4 GPL-4CT batteries to add to the battery bank on the FatDash. These would be delivered right to FatDash’s slip. They would take any old batteries back with them if I wanted.

DSCN3246Now it’s time to get the batteries from the dock into the boat and in the engine room. First is getting the batteries onboard. Not a hard task but at 66.00 lbs. (30.00 kgs) per battery it is quite a work out. Next is taking the batteries down into the boat. 5 steps down. I lifted the battery down to the 2nd step by setting it on the first step and then getting no my knees and moving it down another step. Remember to keep your back straight. The Admiral then lifted it to the deck in the saloon.

DSCN3249That done it is time to get them in the engine room. I have 4 batteries mounted on the starboard side and 3 batteries (1 GPL-4DL and 2 GPL-4CT) on the port side beside the engine. The 2 GPL-4CT batteries on the port side are going into the location where the bad GPL-4DL battery. One bad thing is that the good GPL-4DL DSCN3272must come out to get the 2 GPL-4CT batteries in. After much lifting and grunting I had the batteries in place. Now it is time to get into the engine room on the starboard side and remove the 2 Costco batteries and install the 2 GPL-4CT batteries. Again with some help from the Admiral I lifted each battery to the opening and she placed it on the shower floor. Then we reversed the operation and she placed each GPL-4CT battery in the opening and I put it into the battery box. That’s it, we are done for the day. Next step wiring.

After all the battery changes FatDash will have the following battery capacity.

BATTERY TYPE Cold Cranking Amps Rated Cap. Amp. Hrs. 20 Hr. Rate Minutes of Discharge @ 25A
GPL-4DL 1595 210 390
GPL-4CT (2) 1095 220 492
GPL-4CT (2) 1095 220 492
GPL-4CT (2) 1095 220 492
TOTAL 3285 660 1476

Note: the house is 6 batteries paired in groups of two to deliver 12vdc. For each 2 batteries the voltage is doubled but the current is only the current rating of a single battery.