94 Springer Softail Charging Problem

Discussion in 'Electrical' started by DGriffin, Apr 10, 2009.

  1. DGriffin

    DGriffin New Member

    First off, I am new to the site and apologize if this question has already been asked or answered. My battery is good, I see no voltage increase at the battery no matter what RPM, It starts at 12.5 and after 15 minutes or so starts decreasing down to 11.2 where the bike will no longer start. I suspect the stator or regulator may be bad, Any advice on how to check the stator or regulator is greatly appreciated.
    I'm thinking it may be worth investing in the shop manual,

    Thanks, Don

    NEWHD74FAN Experienced Member Retired Moderators

    Welcome Don to HDTalking, you will find a lot of HD enthusiasts here and plenty of tips in the self help section. Looks like you have a bad battery 12.5 for fully charged battery is a little low and may have a weak or shorted cell. The best way to check is to pull the battery and put it on a battery tender or low current battery charger. While you are at it, clean all the large guage battey cable ends, including the hidden one at the starter, the ground cable bolted to frame and scrape them all with screwdriver or pocket knife till shiny (if you can check the copper strands if visible for corrosion brown or green replace cables). Assemble and coat them all with dielectric grease (HD dealer has it, but automotive parts places can be cheaper).

    Once charged, connect everything back up, aim the bike headlight at a mirror or garage door, you will be checking the brightness of the beam when starting your bike...during the cranking (shade tree machanics CCA check), if the lights dim to 1/4 brightness or goes out while cranking, the voltage available for the ignition is insufficient to start your bike and it is likely a bad battery (if run down to 0 charge more than once the battery reserve will be already degraded). Replace the battery, (after charging the new one overnight and repeating the test.

    If the headlight dims slightly and the starter cranks and engine starts, run the engine till warm. Get your digital multi-meter (DMM) and put test leads across the battery, initial reading with engine not on is 12.8 or more. Start the bike, it may drop during cranking to 11V at most, but once runing you should read 14V or so, if 13V or less your alternator is weak or the regulator is shunting too much voltage away... Rev the engine a bit and it should never rise above 15V. At this point if you suspect either the alternator or regulator, replace regulator first, it is cheaper and more easily replaced...if the alternator/generator it is more costly and difficult weekend project. JMHO
  3. 2000classic

    2000classic Active Member

    Without question, get the HD manual. That and a multimeter and you should be able to pinpoint the problem. No manual, try this. When you have battery out as described above, hook up your meter to the battery at the same time you do the battery tender and watch the voltage. I believe if voltage climbs while on the tender, it should act the same way while in the bike if charging system is working. Voltage goes up while on tender but not when in bike, charging system problem.