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Topic: engine batteries-short life?? (Read 832 times) previous topic - next topic

engine batteries-short life??

Two years ago I both 2 Optima red top engine batteries. Recently I've been having difficulty getting them to start the engine. I check the voltage at the battery and get 12.8v. Shouldn't that be enough to start the 1998 U270?

This morning after having the boost on all night( we're on 50 shore power) again no start. Turns over a bit, then sounds "dead". I felt the batteries--the inboard was almost too hot to touch--the outboard was very warn(not hot). Is this a sign they are bad or is there a boost problem?

The batteries are currently at the Advance Auto store where I bought them -being charged. I'm hoping if they are bad , I'll get  a free replacement set. I'm an optimist I guess.

On a January 22,2012 post I mentioned my concern of "overcharging" batteries when I'm driving. Occasionally, the voltmeter jumps up showing 14-16V. What would cause this overcharging and could this have damaged the batteries?

Dick Lokar

Re: engine batteries-short life??

Reply #1
Two years ago I both 2 Optima red top engine batteries. Recently I've been having difficulty getting them to start the engine. I check the voltage at the battery and get 12.8v. Shouldn't that be enough to start the 1998 U270?

This morning after having the boost on all night( we're on 50 shore power) again no start. Turns over a bit, then sounds "dead". I felt the batteries--the inboard was almost too hot to touch--the outboard was very warn(not hot). Is this a sign they are bad or is there a boost problem?

The batteries are currently at the Advance Auto store where I bought them -being charged. I'm hoping if they are bad , I'll get  a free replacement set. I'm an optimist I guess.

On a January 22,2012 post I mentioned my concern of "overcharging" batteries when I'm driving. Occasionally, the voltmeter jumps up showing 14-16V. What would cause this overcharging and could this have damaged the batteries?

Dick Lokar

The first thing I would suspect would be the series of connections between the starting battery bank and the engine's starter. Corrosion can seriously degrade the quality of these connections. Starting with the connections to the batteries themselves, make sure everything is tight and corrosion free.

Second suspect would be an older battery charger that is giving the batteries a "trickle charge" instead of a "float charge". The old converter/chargers were seriously destructive to batteries. If you are still using the original consider upgrading to a 3-state Progressive Industries (or equal) version.

If everything is ok with those two then it's either the batteries, the cables themselves, the isolator, or.... well... I dunno.

Good luck. :)

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: engine batteries-short life??

Reply #2
Completely charge them.

Go to any place that sells batteries (even Walmart) and have them load tested.

Yes, quite likely that cleaning and tightening battery connections will help.

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: engine batteries-short life??

Reply #3
You mention with the boost on, it still does not start, in that case you might like to check the boost solenoid for working, if it is working, I would be thinking a possible issue with the starter itself.  Having one hot and one warm battery does not give me the warm fuzzy feeling about either battery or your charging setup.
Might be time to contact someone who knows things like this, could be cheaper than guessing.
Just saying
Dave M

Re: engine batteries-short life??

Reply #4
Check your starter, mine was drawing about 2700 amps.  Killed the batteries as well as having to be replaced.  Also, check your ground too.  THat is a reason batteries will not start the coach as well as make them work harder. One very hot and the other not is also pointing to a bad battery.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon