John.
 
The generator kicks in at around 1500 rpm. Until then you won't see much charge 
on the ammeter. It is actually the regulator that kicks in, but we spare us the 
details.
 
All carburetors do have a flat spot where when you open the throttle fast the 
sudden more air provided to the carburetor will result in a lean mixture.
This is due to the fact that the idle fuel system that feeds until around 1000 
rpm is not in demand at higher rm and the main jet starts providing fuel. But 
the main jet is calculated for full throttle rpms , at lower rpm, the suction 
in the ventury is not that great that the fuel can suddenly feed the high air 
demand. At this rpm, the stromberg carburetor runs a little lean. 
See also http://www.ercoupe.info/?n=Main.Carburetion Click on Stromberg diagram.
 
So how can you get a bit richer mixture then? All cars used to have a pump that 
sprayed extra fuel in the throttle when the lever was actuated. The accelerator 
pump. Most Marvel Carburetors do have that pump also. But such a pump adds 
complexity to a system. So Stromberg let it out because there are other means 
to enrichen the mixture.
In our aircraft one can also simply turn on carb heat to enrichen the mixture. 
That way you can overcome the dead spot with ease. It is generally not a bad 
idea to use the carburetor heat on cold days as often as you feel it is needed. 
I usually don't apply carb heat on the climb out, since I like all the 
performance that I can get, but I do not hesitate to apply carb heat on the 
first sign of trouble . Rather less performance than none.
 
I read your carburetor had been overhauled. It seems like they replaced the 
needle that sets the float level and if its done right, the Stromberg is a bit 
on the lean side. I had that on my overhauled carburetor too. If you are used 
to a richer level setting, as it might have been before, you need to learn how 
to deal with the new carburetor. 
The new needle explains also the fuel dripping, that is because the needle is 
not sealing properly in the seat. It might adjust itself for a good fit, maybe 
not. Read through the article on the page mentioned.
 
And your battery might be dead or not. Put it on a charger and see if the 
battery holds the charge after that. 
 
 
By the way. Here in cold Germany we sometimes leave the primer plunger out when 
starting the engine. That provides a trickle charge of extra gas to the primer 
nozzle. 
This extra gas is sometime the only way to keep the engine running for the 
first minute or so until one can take usage of the carburetor heat.
 
 
>From what I read, I think you are still in the green , no need for an extra 
>mechanic.
But you are the pilot in command. You need to do what you think is right.
 
Hartmut
 
 
 



To: [EMAIL PROTECTED]: [EMAIL PROTECTED]: Mon, 8 Dec 2008 10:46:08 
-0600Subject: [ercoupe-tech] Several Questions...




As some know, I had my engine overhauled and added the 0-200 crank under the 
STC.  The first post-overhaul problem I had was with fuel spraying out of my 
fuel cap vents.  This seems to be fixed after adding the fuel restrictor on the 
fuel pump line.
 
At the same time (but not mentioned earlier), I had fuel dripping from the 
carbureator.  My A&P/IA explained that this is common (the carbureator was just 
overhauled too).  It did not leak before.  That one is solved by shutting the 
fuel valve off when the aircraft is parked (at least I no longer find all my 
fuselage tank fuel evaporated after sitting two days).  I assume it may still 
be leaking during flight.
 
Here is my new problem...  Yesterday morning I planned a flight early in the 
morning (beautiful weekend here in Austin, TX area... calm winds and severe 
clear skies).  When I got ready to go, I could not turn the engine over.  The 
temperature in my hangar was 50 degrees farenheit and the plane sat in the sun 
for about 30 minutes (it was probably 40 degrees outside).  I hand propped and 
got the engine going.  After preflight and a warmup at 1000 rpm (fuel pressure 
was in the green),  I tried to do my run-up, it seemed go through fuel 
starvation and the engine died...  Outside again for another hand prop.  During 
run-up same thing.  All my fuel valves were open.  By the way, my amp meter 
showed no charge during the brief period the aircraft was running so I assume 
the battery went completely bad or my generator (also overhauled) went belly 
up.  
 
My A&P came out to the house later in the afternoon.  Now the plane was sitting 
in about 70 degrees of heat.  We had to hand prop and this time the engine kept 
running.  The run up went fine, mag check, carb heat... all went well.  If this 
were the result of my morning attempts, I would have flown.  I did not after 
this as I did not want to have the engine stop at 200 feet during takeoff).
 
My A&P believes the carb needle may have been stuck due to the cold and 
sitting.  That sounds too simple to me, but I want to throw this out to the 
group.  At this point I would like to fly a great Ercoupe mechanic to Austin to 
do a good once or twice over.
 
Ideas?  Offers to make a holiday trip at my expense plus fees?
 
Thanks,
John
 
 





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