Battery testing results

rkinross

I have an Interstate battery Marine - RV deep cycle SRM-24.  I have recently charged it and took it to Advance Auto for a free battery test.  The results came back:

Voltage    12.65v

Measured 475 cca

Rated        550 cca

Temperature 99 degrees F

It also came back with a recommendation to replace the battery.

Are these really bad numbers or are they just trying to sell new batteries.  This is the second year I have owned the boat and do not know the age of the battery.  I have not had starting problems but am going on vacation and want to use the boat for an entire week in early August.  Just trying to get prepared in advance so I do not have problems.

aero3113

I would think during their test your voltage should’ve  be higher. A good number would be higher than 13 volts.

rkinross

@aero3113 Thanks for your reply.  I guess I should just replace the battery.

cruzan

12.7 volts on a conventional Lead Acid battery is 100% charged.

aero3113

Are those numbers of it off the test stand or as it’s being tested?

rkinross

@aero3113 Hi, I took the battery off the boat and charged it at home.  Then I took it to Advance Auto in my car and they brought a battery tester machine out to the parking lot, hooked up a battery tester and printed out the results from their battery tester.  So I would think it is off the test stand as it is being tested.  The machine seems to hold the results for printout.  The device looks alot like a laptop computer but is a little bigger.

rkinross

@cruzan Thanks for your reply.  I am sure the battery is a deep cycle lead acid battery. 

pistole

so for starting , we should be looking for a 1000 CCA battery ?

Cableguy Greg

pistole said:

so for starting , we should be looking for a 1000 CCA battery ?

No, you should be looking for a 1000 MCA battery. Any place that sells marine batteries will be able to direct you in the right direction.

rkinross

@Alswagg This is the battery that came with the boat when I purchased it used.  Would this type of battery cause 'hard to start' issues.  Sometimes it takes awhile to start when the engine is cold.  Starter will crank for 3 seconds and stop.  After awhile it will finally kick over and run. 

rkinross

@Alswagg I took your advice and went out and purchased a 1000 MCA battery.  After installing it the 1982 Chrysler 75 hp engine roared to life on the second try.  That never started so fast since I have owned the boat (2 years).  I was being told by marine mechanics to buy a new starter, new solenoid, new starter clutch and new spark plugs.  Thanks for your good advice.  You saved me a bunch of money on replacing parts needlessly. 

aero3113

That’s what’s so great about this forum!!

pistole

wonderful !