I just did the same LARGE rebuild. I replaced my C-85 with an 0-200
and a TON of other stuff. TTSM is about 21 hours. However to try to
respond to your question, I found I had to add a lobe to drive a
mechanical fuel pump. I also rebuilt the wing tanks.
I have found my fuel burn is very close to before and had no problem
with the system. I love the new 0-200
Kim Blackseth
N 2332H
On Sep 17, 2009, at 3:51 PM, Robert Blanchard wrote:
Group: We have just finished a major rebuild of 415-CD #4787,
N94676 airframe. Restoration work was accomplished by a highly
experienced team composed of an AP and an AP/IA. The C-85-F engine
was majored just prior to my purchase and fitted with the 0-200
modification. Currently, TTSM is 28.6 hrs. As part of the
rebuild, the fuel plumbing system was replaced due to use of
unauthorized components an unworkable plumbing configuration. The
new system follows the configuration shown in Figure 34 of the
Ercoupe Service Manual. All tanks are vented with serviceable
gaskets. The orifice input fitting at the fuel pump was measured
at .062". During post rebuild flight tests, it was discovered
that, although fuel was being pumped from both wing tanks, the flow
rate was insufficient to fully replenish the fuel drawn from the
header tank. This was particularly true with the fuel burn rate
experienced during touch and go landings.
We did not receive any engine performance data on the C-85-0200
engine with the airplane. Fuel consumption data for the C-90 is
appreciably higher than for the C-85. Assuming the C-85-0200 is
reasonably approximated by the C-90 fuel consumption at various
power levels, it occurred that the header tank fuel replenishment
rate for the C-85-0200 may be higher than that allowed by the
current orifice in the fuel pump of .062”. So far, we haven’t
been able to find data on the required orifice for the C-90 or 0200
Continental engines.
First, can anyone provide fuel consumption data for the C-85-0200
engine? Is the C-90 a reasonable approximation? Is the
restriction orifice of .062” adequate for this engine modification,
or should it be relieved? If so, by how much? The fuel system
IS transferring fuel from the wing tanks to the header tank, but
the fuel transfer rate seems to be insufficient. I am concerned
that a fuel burn rate resulting from a long climb at full power
would deplete the fuel from the header tank to an extent it would
take an inordinately long time at cruise to replenish. We would
greatly appreciate any insights, experiences, or recommendations
that might be offered.
Thanks to all.
Bob Blanchard, Owner/Pilot
N94676
Kim Blackseth, ICC, CASp
310 17th St
Oakland, CA
510-839-1760
