Bill,

I have an on-line copy of the 415-D Aircraft Flight Manual that has data for 
the C-85 on Page 5.  C-75 is on page 4.  I also have a newer Univair copy 
somewhere, but I used the on-line one as my primary reference.  Thanks for the 
ordering information.  I'll check with Skyport on getting a copy.

Your thoughts on lean operations are similar to the information the C-120/140 
club has posted on leaning the Stromberg.  Density altitude is the key, not 
MSL.  As I mentioned, we are re-activating mixture control on my airplane 
during the tear-down and rebuild, as well as going back to teh foor brake with 
modified pedal and Skyport STC'ed master cylinder to replace the Piper 
handbrake.

Thanks again,
Dave

--- In [email protected], William R. Bayne <ercog...@...> wrote:
>
> 
> Hi Dave,
> 
> Actually, the 2050 RPM in the 415-D Flight Manual is for the C-75.  The 
> CD also had the C-75, but no Flight Manual.  While the CD model 
> airframe is identical to the 415-D (except for elevator rigging), at 
> the lighter 1260 Lb. Gross, 415-CD performance figures would be 
> "better" than those in the D Model Flight Manual.
> 
> Ercoupes were delivered with a special version of the Continental 
> Operating Manual in addition to the Ercoupe Instruction Manual.  While 
> I eagerly read everything that ERCO published, I also understand that 
> in the years since 1946 technology and experience have changed the 
> "best", or most efficient way to operate our little four-bangers.
> 
> I don't believe X-30012 is available as a download.  Both Skyport and 
> Univair sell Continental Manuals.  Because of the added information and 
> the fact that Continental has continued to update their X30012 
> Operating Manual over the years, I would urge everyone that operates an 
> Ercoupe to purchase and become familiar with the information in this 
> manual.  Order from Skyport (part number "CONTOPS"); or from Univair 
> (part number AC4WM), but verify these as the X-30012 manual.  My copy 
> is February of 1980.  If the version currently shipping is later, 
> please let us know.
> 
> I look to C-90 and 0-200 information in deciding whether cruising at 
> 2575 RPM is (1) safe in terms of stress and (2) consistent with 
> achieving TBO in terms of longevity.  Good practice in the '40's of not 
> leaning below 5,000' is, in my opinion, inappropriate considering that 
> altitude above mean sea level on a standard day is an arbitrary single 
> meaningless value to an engine whose performance instead relates to 
> density altitude.  With the demise of 80/87 fuel, the adulteration of 
> auto fuels, and the excess lead content of 100 LL there is much more to 
> know and to do for the proficient pilot.  With EGT probes on each 
> cylinder, we can now see in "real time" how poor our induction system 
> is at distributing a uniform fuel/air mixture to our four cylinders; 
> and how a bit of carb heat can improve such distribution (and 
> operational efficiency when combined with proper leaning techniques at 
> appropriate en route cruise altitudes).
> 
> Correction(?):  It just dawned on me that those RPMs recently 
> referenced from page 106 and 107 of the Overhaul Manual (X-30010 of 
> 2/80) may relate to test cell break-in operations with a test club 
> instead of a "normal" propeller.
> 
> Regards,
> 
> William R. Bayne
> .____|-(o)-}____.
> (Copyright 2009)
> 
> -- 
> 
> On Nov 19, 2009, at 14:29, bigbrownpi...@... wrote:
> 
> > Bill and everyone,
> >
> > Since you can't achieve 2575 RPM on the ground doing a static runup, I 
> > would say the 2050 RPM in the 415-D Flight Manual for the C-85 is a 
> > more realistic approximation of full throttle.  2000 is just under 
> > what I can get at static full thottle, and I get around 2150 on the 
> > runway as the airplane begins its roll; RPM then increases as speed 
> > increases.  But I agree with your analysis, and that it was probably 
> > related to propeller life as well as engine operating RPM.  I just 
> > don't see the need to do a 2000 RPM run-up to check my mags.  
> > 1700-1800 should suffice as long as I'm also checking my full throttle 
> > RPM on the runway and am prepared to reject the takeoff if I'm not 
> > getting 2100 RPM or above as I start the takeoff roll.  Also agree 
> > that since there is no idle cut-off function for the Stromberg mixture 
> > control, that is not applicable to engines with the NAS3A1.  Just wish 
> > I had a copy of the 1980 X-30012 document to supplement my X-30010.  
> > If you have a PDF or know where to download it, I would appreciate it!
> >
> > Thanks,
> > Dave
>


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