What is the point of the foam insulation around the rectifier? Just wondering since mine is missing 90% of the insulation. Do i need a new rectifier?
Brian
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Rectifier insulation
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LOUD MOUSE
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Re: Rectifier insulation
At one time it was hard rubber to dampen vibration. ............lm
big-b wrote:What is the point of the foam insulation around the rectifier? Just wondering since mine is missing 90% of the insulation. Do i need a new rectifier?
Brian
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LOUD MOUSE
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e3steve
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On the OEM rectifier, which is an 'open plate array' (pre-solid state), each of those heatsink plates is possibly at a different stage of potential within the "bridge". My old one showed some resistive continuity between the plates and the wire tags -- although I knew it was leaky. The AC plates (input from the alternator Bn & Y wires) in a good rec (with no leaky diodes) are not at risk of shorting unless the engine is running. The positive output plate (R or R/W wire) is always at risk of getting shorted to ground and is unfused from the battery post via a dumb terminal on the ignition switch (CB/CL). I'd say the rubber surround-edge was originally partly to dampen the plates' vibrations -- as Ed states -- and also to afford some protection from falling metal tools whilst the seat is off(?). It needs to be 'open' to allow cooling airflow and convection of the heat generated within those old selenium diodes.