Agree with Al, that is basic A&P knowledge (see link below). That being said, the 172 schematic or the A.S. diagram should be a good reference. The gyros actully have the ports labled. The suction port goes to the venturi. AC 43-13 1A chapter 12 para 38 and figure 12 gives a diagram of venturi vacuum systems. here is link. http://www2.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/99c827db9baac81b86256b4500596c4e/$FILE/Chapter%2012-13.pdf Bill A&P-IA
To: [EMAIL PROTECTED]: [EMAIL PROTECTED]: Fri, 22 Feb 2008 15:34:49 -0600Subject: Re: [ercoupe-tech] Vacuum Line Plumbing Look in the Aircraft Spruce Catalog for a simple schematic. Absolutely use the vacuum regulator, if not you may be operating the gyros too fast and although they'll work better, they won't last. The regulator can be set for a max and won't take anything away if you don't achieve it. Finally I just don't know what to say about a licensed mechanic who couldn't figure out how to connect a gyro to a venturi. Must be a big jet mechanic or maybe just a Chevrolet mechanic. Al DeMarzoVisit the Ercoupe Swap Page Free, Easy and No Membership Requiredhttp://www.ercoupeowners.com/swap/swapbook.htm ----- Original Message ----- From: fnelson913 To: [email protected] Sent: Friday, February 22, 2008 3:22 PM Subject: [ercoupe-tech] Vacuum Line Plumbing As my Coupe is finally ready to take to the air again, I have a decision to make relative to vacuum-driven gyros. After getting my panel put back together after the fuselage tank repair and subsequent problems with the airspeed indicator, I am left with the knowledge that my marginal and inoperative gyro instruments owed their lack of functionality to the fact that they were not connected properly to the vacuum source (or in one case – not connect to any vacuum source other than the sound of my deflating wallet). My A&P is confident that he can restore the gyros to their original utility, however he is somewhat lacking in Ercoupe-branded documentation for that purpose. Using the plumbing schematic from a Cessna 172, he can make a reasonable guess in how to hook them up. However, he would be happier if I could find documentation that we can be sure will work with the Ercoupe.I have one large venturi and two vacuum-driven instruments: a directional gyro, and an attitude gyro. There is a vacuum regulator which may not be of value if I am going to need all the vacuum that the single venturi can produce. There is also a vacuum gauge that has never indicated any vacuum since it is not connected to the system at all.My decision to scrap the entire vacuum system and vacuum-driven gyros is partly depended on whether or not I can get them working given reasonable expense, effort and aggravation. This is my question: Where can I find a schematic or other documentation on how to do the vacuum line plumbing for these instruments?As always, thank you all for the time that you devote to helping others in this forum.p.s. – I will start writing my report on the rudder pedal installation this weekend. I hope to have it posted here in a couple of weeks.Frank NelsonN51DV – 415C (finally out of annual)TOA/California _________________________________________________________________ Shed those extra pounds with MSN and The Biggest Loser! http://biggestloser.msn.com/
