RE: [COUPERS-TECH] 46Coupe

[dneddinger]

I have never heard of a positive ground on a airplane but of course I haven't heard about a  bunch of things. I would check very carefully before changing any thing around. No avionics  I know of now days uses such a set up and they are very sensitive to the proper polarity. Like they will go up in smoke in most cases if it is reversed. I have about 40 years in electronics so  I am talking from experience. Some one would have to have re wired the starter for it to turn the  engine in the proper rotation. In most cases a dc motor such as starter will run either direction by just reversing the polarity. What kind of starter do you have ? Again I would check very close  and make sure you have a positive ground !!!!!!!!!!!!!!!!!     DICK  NANCY & SOPHIE                -------Original Message-------   From: Ed Burkhead Date: 06/12/05 20:30:10 To: 'Charles Waldo'; Coupe-Tech Subject: RE: [COUPERS-TECH] 46Coupe     Charles,   If it truly is positive ground right now, you will probably want to change that around – carefully.   I’m not an EE, but I remember my most basic electronics, I think.   Many items (light bulbs, for example) don’t care which way the electrons flow.   Those that do, just want the positive on one lead of the power cable and negative on the other lead – they don’t care if it’s the positive lead connected to the fuselage or visa versa.   I’d change it round but first I’d go through EVERY electrically operated item in the plane and consider if it needs to have the wires switched around.   Let’s see – oil pressure gauge – no problem tachometer – no problem ammeter – must be switched altimeter, air speed, VSI, etc., no problem electric turn and bank – must be switched radios – must be switched intercom – if running off airplane power, must be switched rotating beacon or strobes – must be switched starter / regulator – must be switched (I think)   You get the idea.  You guys can figure this better than I can.   Due to the negative ground convention being so universal, changing now will prevent a very unhappy moment someday when you hook up a transponder or GPS or whatever.  _____________________   Fuel nose-tank overflow.  Restrictor in the fuel line just after the fuel pump is the first thing to check.  Next would be the overflow outlet and fuel-lines back to the wing tanks.  (Hope it’s the easy restrictor.)   A&P mechanics are not that accustomed to fuel line restrictors since fewer and fewer of them have dealt extensively with old airplanes with gravity feed header tanks.  (Does any other plane have this arrangement besides Ercoupes?)  _____________________   I bought my Coupe unflown, too.  Mine was also down for maintenance when I bought it.   Every printed word published in book or magazine about Fred Weick or Coupes from 193x to present was my Coupe flying education. I did NOT regret it.  I loved that plane.  ( For my one complication, see http://ercoupe.org/Fly-in%20Reports/Gas-line-ice.htm )   Ed Burkhead http://edburkhead.com ed -at- edburkhead???.com          (change -at- to @ and remove "???")   From: Charles Waldo [mailto:[EMAIL PROTECTED] Sent: Sunday, June 12, 2005 8:59 PM To: Ercoupe Tech Subject: [COUPERS-TECH] 46Coupe     ----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]----     ============================================================================== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/ ============================================================================== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/