Re: Optima Red Top Reply #25 – November 04, 2011, 11:29:29 am Kent in reply #10 you said: "At times when I turn on the key the gauge shows only 12V......".My dash voltmeter reads about 1 volt low. I use a digital voltmeter for testing and it takes a few seconds to stabilize indicating resistance in the wiring harness - another winter project.Pierce in Reply #24 Great article on "Standing Loss Discharge" but there was no mention that the "Standing Loss Discharge" of Gel batteries is magnatudes slower than flooded. AGM batteries are also superior to flooded in this regard. Quote Selected
Re: Optima Red Top Reply #26 – November 04, 2011, 11:38:01 am Pierce, You are correct on the battery discharging slower in a colder state.However, when the battery gets colder, its capacity goes down faster, this is why most battery folks in the colder parts of the world recommend a battery heater to keep the battery capacity up where it can start the equipment. SO it is one of em subjects, how cold, how many amps you need to start your equipment, even down to the point of oil viscosity, as many things contribute to hard cranking/starting engines.Just one of those subjects where the happy exact middle can be elusive, made for deep discussion, thoughts and opinions. Quote Selected
Re: Optima Red Top Reply #27 – November 04, 2011, 02:06:36 pm Yes, the cold temps do reduce the battery capacity but with three back there even in the low teens the Detroit spins over as fast as usual even after sitting for a week. I still have that bad injector so the batteries really get a test in cold weather but I don't have to use boost. The turbo version as you pointed out , does have a little lower compression ratio so this may be why it spins so fast (or has no compression ). With our 8V-71s, we had to use the battery switch in the "both" position as one 8D was marginal.Assuming you mean using a battery heater just before starting to bring an engine out of hibernation. Heating the battery otherwise would just start the discharge cycle. Sounds like a single battery application.In reading the excerpt, the 1.225 SG reading for sulfation onset is a good one to remember.Sure wish I could find a good source of reasonably priced DDEC injectors. I could replace the old mechanical injectors for about $50 each, a real buy considering they are the injection pump and injector combined. The new electronic injectors are expensive and from reading a lot of boat forums, the opinion was that the mechanic had to bring eight Reliabuilt injectors to the dock to do a 6V-92TA as the rejection rate was 25%. In calling around, I understand they are difficult to rebuild and calibrate with only one or two rebuilders in the states.I suppose I seem super Scrooge like but since I don't qualify for medicare, I need a big kitty for possible medical expenses down the road. On a normal morning, I get 4 cylinders instantly, one a second later and the last a couple of seconds after that. The colder it gets, the longer it takes to get all six going. Compression is fine so the pattern is bad. Have tried manually pumping up the system to 12 lbs or so but still the same. Good trick is to wait until the last cylinders fire on a cold morning, turn it off and go back and feel the exhaust manifold next to each port. The cold ones are the bad ones so I do know my offending injectors. The 8V-71s spoiled me as they started faster than instantly even in cold weather. Kent and Wyatt,Check the voltage at the battery with a digital voltmeter and then use a hydrometer. The best way to see the health of your batteries. Pull the terminals off and check each one as one bad apple... And: yes, my house batteries "standing loss discharge" is super low. I just bought another back from my neighbor that I got for him over a year ago and it still had 12.4V after over a year just sitting on the shelf in his garage. (but it sells at the dealer for $300) Quote Selected
Re: Optima Red Top Reply #28 – November 04, 2011, 02:19:25 pm The battery heater is a 24/7 heater, not HOT, just warm to keep the capacity of the starting battery up to snuff. As for the injector issue you mention, Have you tried running a heavy dose of injector cleaner through the system, Cummins has a super cleaner, 2.5 gal metal can, run it thru and you have a new engine. I have found it to work well on the mechanical 71's and 92's, I have never played much with the DDEC versions.And yes fully understand temps in the teens, that is not COLD. IN cold areas, they drain the warm oil and remove the battery from the equipment, no matter if dozer, airplane or just diesel engines, keep inside and warm over night, then reinstall in the morning, other wise getting it running is a very iffy thing. Different folks, different experiences. Quote Selected
Re: Optima Red Top Reply #29 – November 04, 2011, 02:44:17 pm Is this the Florida citrus freeze we read about? Yes, understand below -45 degrees, car springs break, shocks don't work, planes don't start. Alaska has plugins for parking on the street.Have tried lots of heavy duty cleaner with low fuel tanks so will pull the two out and give them a ultra sonic cleaning with Gaylie's jewelry cleaner. Quote Selected
Re: Optima Red Top Reply #30 – November 04, 2011, 04:13:40 pm Pierce: Gel and AGM batteries are sealed, and the caps are not removeable, so cannot be checked with a hydrometer. I had a Gel 8D sit for a year outside in the heat and cold without a charge. I checked it every month. At 12.65v, I put a smart trickle charge on it for a week, after which it stabilized at 12.85v.I agree that generally, more expensive batteries are better. Quote Selected
Re: Optima Red Top Reply #31 – November 04, 2011, 04:37:24 pm Yup Never thought of polishing the outside of an injector, but then I never put one on display. Quote Selected
Re: Optima Red Top Reply #32 – November 05, 2011, 08:57:31 pm FWIWI repaced my RED TOP's last summer. They were original's, installed Spring of 1993.I went back with red tops Quote Selected
Re: Optima Red Top Reply #33 – November 06, 2011, 09:35:39 pm Keep in mind that with a Sam's Club $35 annual membership, our Optima SC34U RedTops were $150 each out the door. RedTop Optima's have a 3-year full (not pro-rata) warranty. We find Optima's to be a good starting battery at a good price, all with no maintenance. Quote Selected
Re: Optima Red Top Reply #34 – January 29, 2012, 08:40:18 pm 1. Are the Red Top or the Gold Top batteries best for the chassis (cranking)? 2. What should be the voltage on the engine batteries? In PDI mine were charged over night, separated and load tested, and none dropped below 10.2 volts at 900 amps. Is that "good enough"?Thanks,Note: I have had this coach a very short time, I am checking things. I understand the engine (chassis) voltage reads out on the dash gauge and the house batteries on your camera/monitor. In a prior coach, I had briefly, the engine voltage would fall to about 11 as cranking (with boost on). As soon as the engine cranked, the gauge would go to about 14 volts. This ISM takes more than a couple of seconds to spin fast enough to start, thus my question about battery condition. Quote Selected
Re: Optima Red Top Reply #35 – January 29, 2012, 09:32:56 pm I chose Optima Red Top for the chassis batteries. I based my decision on information I found here: Optima Battery FAQ - Frequently Asked QuestionsOther folk may be able to provide an interpretation of your load test. Quote Selected
Topic: Optima Red Top