Bad Voltage Regulator ?
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
most multi meters have an ammeter function.
mike
Road Master
Joined: Jun 2010
Posts: 1,221
Likes: 4
From: Annemasse (border of Geneva-Switzerland) facing Mt-Blanc.
Our VR carries 6 diodes to rectify AC into DC voltage, a voltage limiting device (possibly Zener) to output/clamp 14.5V plus a thermal load (resistor) to evacuate excess/unused power produced by the permanent field (magnet) alternator.
So it's not just a voltage you must look for.
If one of these 3 functions inside the VR package is damaged it will either not draw any current or draw too much.
seeing all these voltage issues does anyone think that putting the oil cooler underneath the VR has anything to do with it(overheating)seems they put the VR out in the wind to cool it down just to put a 200f oil cooler under it?
Road Master
Joined: Jun 2012
Posts: 1,062
Likes: 191
From: Boise, Idaho
Yes, the voltage regulator or oil cooler should be moved. There is entirely to much heat being applied to the voltage regulator by the oil cooler. This is a bad design by Harley.
Road Master
Joined: Jan 2011
Posts: 855
Likes: 6
From: Riverside, Ca.
OK, just got back from dealer and they pulled the codes which read there was definetly a voltage drop at one time. Duh...... They will not replace the VR until it happens a second time. They noted the problem on a Work Order and said MoCo will not authorize a new VR unless it happens a second time. Mine did not fall into the recall so looks like I have to run it until it happens again. Not desirable to me with the upcoming trip so I thought OK I will buy a new regulator myself....until I found out they were around $300.00. Sooooo I am going to run it as much as possible over the 4 days and hope it acts up again or head to Kentucky with my fingers crossed. Dealer did say I can run it about 4-5 hrs with low voltage till I get to another dealer in the area. BS, but what else can I do without spending the $300 that I may or may not have to.
Road Master
Joined: Jan 2011
Posts: 855
Likes: 6
From: Riverside, Ca.
over-simplified.
a bad VR may appear to work correctly at times, or it may work partially
1st: voltage always needs to be checked at the battery. you can use a tender pigtail if you have one.
if those readings confirm low voltage, You should check the charging system. the diagnostics have been posted many times on the tech board/ electrical
if those readings show high voltage ( above 14.8), you have trouble
this be as simple as a loose wire or cable, check those
the VR converts AC voltage from the stator to DC, it also limits voltage to below 14.8 Volts ( excess voltage is converted to heat and shed with the cooling fins- never use one of those chrome covers)
if you see voltage higher than that it is bad, if current drains back to the stator when the bike is parked it is bad ( bad diode), if it allows AC current to pass, it is bad ( bad diode).
mike
a bad VR may appear to work correctly at times, or it may work partially
1st: voltage always needs to be checked at the battery. you can use a tender pigtail if you have one.
if those readings confirm low voltage, You should check the charging system. the diagnostics have been posted many times on the tech board/ electrical
if those readings show high voltage ( above 14.8), you have trouble
this be as simple as a loose wire or cable, check those
the VR converts AC voltage from the stator to DC, it also limits voltage to below 14.8 Volts ( excess voltage is converted to heat and shed with the cooling fins- never use one of those chrome covers)
if you see voltage higher than that it is bad, if current drains back to the stator when the bike is parked it is bad ( bad diode), if it allows AC current to pass, it is bad ( bad diode).
mike
Road Master
Joined: Jun 2010
Posts: 1,221
Likes: 4
From: Annemasse (border of Geneva-Switzerland) facing Mt-Blanc.
Stay away from the 10 and 50V scales because parallax error will induce operator error. Buy it now, keep it forever.
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