Howdy all!
I have an S-2A produced near the end of the line with an AEIO-360-A1E. It has an (original?) Prestolite VSF 7203 voltage regulator and a separate Prestolite Overvoltage Control... X17621 is on it, but not sure if that's the part number.
Question is... if the voltage regulator screw is twisted to give around 13.8v, all is well. I've read that 14.2v is best for battery longevity and if it's turned up that little bit, it'll read that and be great about 80% of the time. The rest of the time it will be wildly uncontrolled, sometimes hitting 20v for as long as I leave the alternator switch on and other times it will spike to 17v. No amount of turning off and back on again seems to do anything smart, it just goes back to normal on it's own, in its own time. These voltages are read off an EDM-900 engine monitor (which thankfully has a flashing warning light for anything out of parameters).
Secondary question... is this just a "failed in that screw position" regulator and an inop/flaky overvoltage regulator? Something else? Is there a commonly agreed upon upgrade/replacement for the S-2A that simplifies/cleans up/reduces weight of these necessary functions? This is a certified airplane used for instruction so no experimental solutions are possible. Local mechanics are not super familiar with small piston airplanes. Thanks in advance!
Also, if it makes any difference in futureproofing, I've been looking into an EarthX Lithium battery once my current Gill gives up the ghost (and once the EarthX becomes STCd... any day now). Have to do more research about weight and balance but the VR and OVR would need to work with this battery ideally.
I have an S-2A produced near the end of the line with an AEIO-360-A1E. It has an (original?) Prestolite VSF 7203 voltage regulator and a separate Prestolite Overvoltage Control... X17621 is on it, but not sure if that's the part number.
Question is... if the voltage regulator screw is twisted to give around 13.8v, all is well. I've read that 14.2v is best for battery longevity and if it's turned up that little bit, it'll read that and be great about 80% of the time. The rest of the time it will be wildly uncontrolled, sometimes hitting 20v for as long as I leave the alternator switch on and other times it will spike to 17v. No amount of turning off and back on again seems to do anything smart, it just goes back to normal on it's own, in its own time. These voltages are read off an EDM-900 engine monitor (which thankfully has a flashing warning light for anything out of parameters).
Secondary question... is this just a "failed in that screw position" regulator and an inop/flaky overvoltage regulator? Something else? Is there a commonly agreed upon upgrade/replacement for the S-2A that simplifies/cleans up/reduces weight of these necessary functions? This is a certified airplane used for instruction so no experimental solutions are possible. Local mechanics are not super familiar with small piston airplanes. Thanks in advance!
Also, if it makes any difference in futureproofing, I've been looking into an EarthX Lithium battery once my current Gill gives up the ghost (and once the EarthX becomes STCd... any day now). Have to do more research about weight and balance but the VR and OVR would need to work with this battery ideally.
