[COUPERS-TECH]

[Donald Veness]

----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]---- I have a 415C, bought as a basket case with fresh O/H'ed Cont. 85 H.P. engine in the fall of 2000. After several repairs, couple modes., new windows, new interior, wings recovered and new paint I flew it for the first time last fall. The airplane flew well, nice and stable, good power, all instruments worked; however I could feel a vibration above 2000 RPM in the control wheel, floor board and instrument panel. I checked mages, plugs, leads, intake leakage and mount bushings. Checked all baffling and cowling for contact between engine mount and fuselage. Moved prop through all six bolt locations to no avail. Borrowed another prop and thought the vibration was somewhat better. Sent my prop out for O/H. It failed (blade cord below limits at 2 stations); so I bought a new Sensenich prop. Installed new prop, same condition. I moved prop through all six locations, same condition. Swapped all components (mages, leads, plugs and carb.) from another 85 power A/C that was running good, same condition. Now I am getting desperate. Swapped engines between Ercoupe and another aircraft (Rearwin Skyranger). Ercoupe engine on Skyranger ran good with no vibration; but Ercoupe with Skyranger engine still has same vibration problems. Now it is to the extent it is chewing up the lower right rubber mount bushings.   I should note the engine mount was repaired on the lower two tubes but fit the firewall well. It is misaligned somewhat at the lower right engine boss; but I feel this is no more than I have encountered on other aircraft. During the last 4 or 5 months I have talked with several people on this subject. Most all suspect the mount. Due to the cost of a new mount, I would like to be 95% sure a new mount will cure this problem. Can anyone shed some light on what this problem could be? After 3 props, 2 engines and substituting various parts between two engines; I am ready to try anything at this point.   Sincerely, Don Veness 198 Hofmeister Rd, Petersburg, Ohio, 44454 Phone 330 426 4035                           ============================================================================== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/