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Generator 3rd brush
Posted: Wed Sep 11, 2019 8:01 am
by trebot
Have 12v generator on a KL. What is procedure for adjusting 3rd brush? Thanks
Re: Generator 3rd brush
Posted: Sat Feb 01, 2020 7:51 pm
by George Emmanuel
I'm scrolling through all posts tonight and saw yours from some time back.
I too am dealing with the 3 brush generator on my KLC. Chris Craft used the Autolight generators and they are different from the Delco. The Delco has a screw on the rear housing of the generator that locks the 3rd brush in place. Per a Google search on Autolight, the Autolight's 3rd brush is adjustable also, but does not have a locking screw. It (Autolight) is held in place by friction. So before attempting an adjustment on the generator in my boat, I went to my parts motor to experiment w/out causing damage.
Remove the cover band from the back of the generator and locate the 3rd brush. The other 2 are permanently in place and if you look carefully, you can determine the 3rd brush. It has a long wire coming from the field windings that allows for movement back and forth. You can use your finger to push back or pull forward (towards the direction of rotation) that brush holder assembly. Pulling the brush holder towards the direction of rotation increases the charging rate, and pushing it away decreases the rate.
Per past discussions you want to set the charging rate so there is a slight charge when all lights/accessories are on. Apparently that translates into 4-5amps when no accessories are on other than the engine. That prevents the battery from being overcharged under normal operation.
I hope I did an understandable explanation. If it is incorrect, I hope someone else will chime in, but I'm confident in what I said.
George